List of Abstracts

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1-Title: Study of transients in the era of large telescopes and surveys
Author: G. C. Anupama  1, @  
Affiliation: 1: Indian Institute of Astrophysics
Abstract: Time-domain astronomy will be an exciting area of research in the future, thanks to the synergy with various surveys from on-going and up-coming facilities and the multi-messenger follow-up studies. I will discuss in the talk a few science cases relevant to the eruptive transients that will be of interest in the era of the future large surveys and large telescopes.

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2-Title: The role of IFU science in the context of the future large scale facilities.
Author: Roland Bacon  1, @  
Affiliation: 1 : Centre de Recherche Astrophysique de Lyon
École Normale Supérieure - Lyon, Université Claude Bernard Lyon 1, Institut national des sciences de l\'Univers, Centre National de la Recherche Scientifique : UMR5574, Institut national des sciences de l\'Univers
Abstract: In a few years, large scale facilities such as JWST, ELT, TMT, LSST, Euclid, SKA, 4MOST, WEAVE will provide a wealth of information in the field of galaxy formation and evolution. In this talk, I will detail what could be the role of IFU science, such as the one provided by the current facility (e.g. MUSE) or future instruments (e.g. BlueMUSE, NIRSPEC IFU, HARMONI), with respect to the other type of instrumentations (High-resolution Optical-IR imaging, Radio observations, Multi-Object Spectroscopy).

3-Title: Exotic image formation in strong gravitational lensing
Author: Jasjeet Bagla  1, @  
Affiliation: 1: Indian Institute of Science Education and Research Mohali
Abstract: I will discuss the frequency of exotic image formation in strong gravitational lensing by clusters of galaxies. It is found that this frequency is much higher than earlier estimates and this offers us an opportunity to refine lens models as well as use these image formations to probe the high redshift universe. I will describe the methodology used in our analysis and also discuss sources of uncertainty. I will close with predictions for upcoming instruments and surveys.

4-Title: Star formation rejuvenation of the stellar bar in nearby disc galaxies.
Author: Sudhanshu Barway  1, @  
Affiliation: 1: Indian Institute of Astrophysics
Abstract: The presence of the stellar bars has important implications for disc galaxies due to their deep connection with the dynamical and secular evolution of such galaxies. More than 60 percent of disc galaxies that dominate the star formation in the local universe are known to host strong stellar bars. Although bars exist at redshift z ~ 1−2, it remains unclear when disc galaxies formed their first bar. In the absence of legitimate evidence and clues, it remains a more challenging problem to understand whether the same bar continued to exist in the present-day galaxies or it has been dissolved and rejuvenated. In this talk, I present the work in which we made use of the color measurements from multiband, multicomponent 2D decompositions of disc galaxies using SDSS images along with spectroscopic investigation to understand the challenges of star formation histories in the stellar bar in nearby disc galaxies.

5-Title: Women in Astronomy Worldwide
Author: Jocelyn Bell Burnell  1, @  
Affiliation: 1: Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Rd, Oxford OX1 3RH, UK.
Abstract: The International Astronomical Union, the world-wide body for professional astronomers, records its membership data segregated by gender.  I examine this data to see how the fraction of astronomers that is female (or registered as female)  is changing with time and by country and reflect on what this data is telling us.  I will describe the Athena-SWAN initiative that started in the United Kingdom and what changes that have brought about.


6-Title: Status of the commission femmes & astronomie of the SF2A
Author: Caroline Bot 1, @  
Affiliation: 1 : Observatoire Astronomique de Strasbourg,11 rue de l universite, 67000 STRASBOURG
Abstract: In 1912, Édmée Chandon was the first woman to be a professional astronomer in France. The first of many to follow, but this number has not raised as much as one could hope. Today, only 23% of permanent positions in astronomy in France are held by women (Bot & Buat 2020). Why so few? Are there specific obstacles faced by women in astronomy? 

The commission femmes & astronomie (women & astronomy) of the French society of astronomy and astrophysics (SF2A) was recently created. It aims at promoting equality between men and women and raising awareness on related issues (sexual harassment, discrimination, unconscious biases, …) that may occur in a research environment, and more specifically in the French A&A community. 

I will present the current context of women & astronomy in France and the actions undertaken by the SF2A women & astronomy commission.

7-Title: Far-infrared to radio dust emission in nearby galaxies: a challenge to dust models?
Author: Caroline Bot 1, @  
Affiliation: 1 : Observatoire Astronomique de Strasbourg,11 rue de l universite, 67000 STRASBOURG
Abstract: Since the 1980s, satellites like IRAS, DIRBE, ISO, Spitzer, AKARI, Herschel and Planck have gradually paved the far-infrared to millimeter spectral energy distribution of galaxies. Ground based sub-millimeter and millimeter facilities (Apex, JCMT, IRAM, SMA, ALMA) have been complementing these SEDs at higher resolution and sensitivities. These observations have been filling gradually our understanding of the shape of the thermal and non-thermal dust emission. Different dust models have taken these observations into account and factored it in to make our understanding of dust properties evolve. I will review some of this shared history of evolution between far-infrared observations and dust models. At longer wavelengths, radio emission of galaxies is most often dominated by synchrotron emission. Yet, the free-free emission from the ionized gas contributes to the long frequency emission range and super-imposes to the dust emission in the millimeter and sub-millimeter wavelength range. Around 1cm, anomalous emission (AME) from small and fast-rotating grains also needs to be taken into account, even if it has only seldomly been observed in galaxies (but widely observed in the Milky Way). Finally, foreground and background emission to the galaxies studied and the inhomogeneities of these background sources (cirrus, CMB fluctuations, CIB, …) have to be taken into account as well. In order to study and model dust emission from observations, a challenge is hence also to subtract, disentangle (component separation) or factor in the modeling process the different sources of emission observed.

I will make an overview of these issues and how it impacts our current understanding of the dust emission in the millimeter to centimeter wavelengths, where our knowledge of far-infrared of radio emission shape is extended and other sources get intertwined.


8-Title: FIRST Winged Radio Galaxies with X and Z Symmetry
Author: Soumen Bera  1, @  , Sabyasachi Pal  2  , Tapan Sasmal  1  , Soumen Mondal  1  
Affiliation: 1: Jadavpur University, 2: Midnapore City College
Abstract: X-shaped radio galaxies (XRGs) are a subclass of radio sources that exhibit a pair of secondary low surface brightness radio lobes oriented at an angle to the primary high surface brightness lobes. Sometimes, the secondary low brightened lobes emerge from the edges of the primary high brightened lobes and form a Z-symmetric morphology. We present a systematical search result for XRGs and Z-shaped radio galaxies (ZRGs) from the VLA Faint Images of the Radio Sky at Twenty-Centimeters (VLA FIRST) Survey at 1.4 GHz. Our search yields a total of 296 radio sources, out of which 161 are XRGs and 135 are ZRGs. We have also made optical identification of these sources from the different available literature. J1124+4325 and J1319+0502 are the farthest known XRG and ZRG, respectively. We have estimated the spectral index and radio luminosity of these radio sources and made a comparative study with previously detected XRGs and ZRGs. The average value of luminosities for XRGs is higher than that of ZRGs. With the help of a large sample size of the newly discovered XRGs and ZRGs, various statistical properties of these sources are studied. Out of 161 XRGs presented in the current paper, 70% (113) are FR II radio galaxies, and 13% (20) are FR I radio galaxies. For 28 XRGs, the morphology is complex and could not be classified. For XRGs, statistical studies are done on the angle between the major axis and minor axis and the relative size of the major and minor axes. For the ZRGs a statistical study is done on the angular size.

9-Title: Studying low surface brightness galaxies in the future.
Author: Samuel Boissier  1, @  , Junais Snc  2, @  
Affiliation: 1 : Laboratoire d'Astrophysique de Marseille  (LAM)  -  Website
INSU, CNRS : UMR7326, Aix Marseille Université
Pôle de l'Étoile Site de Château-Gombert 38, rue Frédéric Joliot-Curie 13388 Marseille cedex 13 -  France, 2 : Laboratoire d'Astrophysique de Marseille, Aix Marseille Université : UMR7326
Abstract: In recent years, we have re-discovered the low surface brightness realm, owing to progress in telescopes and instruments. The famous Giant Low Surface Brightness (GLSBs) Malin 1 has been revisited (Gaspar et al. 2015, Boissier et al. 2016, Junais et al. 2020), while new malin-1 like galaxies were discovered (e.g. Hagen et al. 2016). At the same time, Ultra-Diffuse Galaxies (UDGs) became suddenly a new family of galaxies (Van Dokkum et al. 2015, Koda et al. 2015). While some of them are red and passive, filed blue galaxies were also discovered (Leisman et al. 2017, Prole et al. 2019), with a possible transformation scenario from one into another in clusters (Junais et al., in preparation).
Are GLSBs like Malin 1 common during the history of the universe? We do not know because their stellar emission is hard to detect, however, they are gas-rich and massive, offering a possibility to detect them with SKA! Are there more gas-rich UDGs in clusters at an earlier time? Again, the only answer can come from the new insight that can we may get with SKA. Efficient Optical/IR spectroscopy will also be crucial to bringing more information on these faint sources (redshift, stellar population features).
I will discuss some aspects of the current status in the study of GLSBs and UDGs and the possibilities that will arise in the future for their study.

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10-Title: First multi-redshift limits on post-Epoch of Reionization (post-EoR) 21 cm signal from z = 1.96 - 3.58 using uGMRT
Author: Arnab Chakraborty  1, @  
Affiliation: 1: Indian Institute of Technology, Indore (IIT Indore)
Abstract: Measurement of fluctuations in diffuse HI 21 cm background radiation from the post-reionization epoch (z < 6) is a promising avenue to probe the large-scale structure of the Universe and understand the evolution of galaxies. We observe the European Large-Area ISO Survey-North 1 (ELAIS-N1) field at 300-500 MHz using the upgraded Giant Meterwave Radio Telescope (uGMRT) and employ the ‘foreground avoidance' technique to estimate the HI 21 cm power spectrum in the redshift range z = 1.96-3.58. Given the possible systematics that may remain in the data, we find the most stringent upper limits on the spherically averaged 21 cm power spectra at k~1.0 Mpc^-1 are (58.87 mK)^2, (61.49 mK)^2, (60.89 mK)^2, (105.85 mK)^2 at z = 1.96,2.19,2.62 and 3.58, respectively. We use this to constrain the product of neutral HI mass density (Omega_HI) and HI bias (b_HI) to the underlying dark matter density field, [Omega_HI*b_HI], as 0.09,0.11,0.12,0.24 at z=1.96,2.19,2.62,3.58, respectively. To the best of our knowledge, these are the first limits on the HI 21 cm power spectra at the redshift range $z = 1.96 - 3.58$ and would play a significant role to constrain the models of galaxy formation and evolution.

11-Title: Of shocks and environments: Exotic Stellar Demise
Author: Poonam Chandra  1, @  , Roger Chevalier, @
Affiliation: 1: National Centre for Radio Astrophysics-Tata Institute of Fundamental Research
Abstract: Massive stars end their lives as one of the most exotic explosions in the cosmos, i.e. supernovae. Mapping the various kinds of supernovae to their progenitors is a big mystery in stellar evolution. While archival survey data are limited to nearby supernovae, radio and X-ray studies provide unique input to unravel the progenitor stars of supernovae. Radio and X-ray observations trace the interaction of supernovae shocks with the surrounding medium, retracing the mass-loss history of the progenitor star. However, simple models assume a homogeneous shock and a constant mass-loss rate wind medium. Both of these predictions can be tested via well-sampled radio observations of supernovae. In this talk, I present well sampled long term radio and X-ray observations of two stripped-envelope supernovae (which have lost their H and He envelops) with the low frequency upgraded Giant Metrewave Radio Telescope (uGMRT) and high-frequency Karl G. Jansky Very Large Array (JVLA) telescope along with X-ray data from Chandra and Swift-XRT. Our late-time observations allow us to probe the conditions of the star in its early nucleosynthesis stages. Both indicate the presence of dense shells surrounding the respective progenitor star. While in SN 2001em dense shell can be modeled as 3M⊙ H envelope ejected 1000 years ago, the dense shell in SN J1204 appears just around 50 days after the explosion and suggests a more recent enhanced mass-loss rate history. We show that radio observations remain the best probe to investigate progenitor stars in their last stages leading to supernovae.

12-Title: SKA France
Author: Catherine CESARSKY  1, @  
Affiliation: 1: CEA, Saclay, France
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13-Title: Extra-Galactic Planetary Nebula studies with MSE
Author: Chinnathambi Muthumariappan  1, @  
Affiliation: 1: Indian Institute of Astrophysics, Bangalore
Abstract: Planetary Nebulae studies in nearby galaxies using MSE multiplex capabilities will be discussed

14-Title: The Legacy Survey of Space and Time (LSST) with the Vera C. Rubin Observatory
Author: Johann Cohen-Tanugi  1, @  
Affiliation: 1 : Laboratoire Univers et Particules de Montpellier
Université de Montpellier, Centre National de la Recherche Scientifique : UMR5299
Abstract: I will give an overview of the Vera C. Rubin Telescope and its forthcoming nominal 10-year survey, with emphasis on science prospects and potential synergies with SKA, especially in the context of cosmology and extragalactic astronomy.

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15-Title: Testing the role of external UV radiation on the disk evolution in W5 clusters
Author: Belinda Damian  1, @, Jessy Jose  2, @, K. T. Paul  3, @  
Affiliation: 1: CHRIST (Deemed to be University), Bangalore, India, 2: Indian Institute of Science Education and Research Tirupati (IISER Tirupati), India, 3: CHRIST (Deemed to be University), Bangalore, India
Abstract: The circumstellar disks (or protoplanetary disk) are a natural by-product of the star formation process. The evolution of these disks can be attributed to the accretion of the disk gas and dust onto the star, accretion into planets, photoevaporation due to the central protostar, or due to external UV radiation from nearby massive stars. Studies have shown that the evolution of disks is dependent on the stellar mass and that the disk frequencies around solar to high-mass stars are lower in comparison to the disk frequencies around low-mass stars. This correlation between the disk fraction and stellar mass indicates that the time available for planet formation around massive stars is less. Hence, it is important to understand the relation between disk fraction versus age as a function of stellar mass and the dependence of disk frequency on environmental factors. In this regard, the young clusters (age ~2Myr) IC1848-East and West located at a distance of ~2.2kpc in the W5 giant molecular cloud complex with negligible extinction (Av ~ 1.5 mag) serve as ideal targets. Using deep multiband photometry from CFHT (Megaprime), PanSTAARS, Mayall Telescope (Newfirm), and Spitzer (IRAC, MIPS) we compare the disk fraction as a function of mass and UV flux between the two clusters through SED analysis. We also study the effect of age, mass, and UV flux on the disk color excess. Since the two target clusters are located at the same distance with similar age and negligible foreground extinction but experience varying amounts of external radiation from the massive stars, this comparative study can provide evidence for the role of environmental factors on disk evolution.



16-Title: Estimating the Flattening of Galaxy Halos Using HI Observations
Author: Mousumi Das  1, @  , Stacy Mcgaugh  2, @  , Roger Ianjamasimanana  3, @  , James Schombert  4, @  , K.s. Dwarakanath  5, @  
Affiliation: 1: Indian Institute of Astrophysics, 2: Case Western Reserve University, 3: Rhodes University, Grahamstown, 4: University of Oregon [Eugene], 5: Raman Research Institute
Abstract: It is well known that the neutral hydrogen (HI) rotation curves of disk galaxies can trace their dark matter mass. However, in recent years with improved HI observations of galaxies, the HI velocity dispersion can also be traced out to large radial distances in galaxies. This helps us to determine the dynamical mass associated with galaxy disks in the outer parts of galaxies where there is no star formation and very little stellar mass. In this presentation I will describe how HI observations can be used to determine the halo parameters of galaxies, focusing on how HI velocity dispersion can be used to trace disk dark matter and the halo shapes of galaxies. Our results clearly show that the halo shapes are different for disk galaxies compared to gas-rich dwarfs.

17-Title: A Comprehensive study of interesting neglected close binaries
Author: Shanti Priya Devarapalli  1, @  
Affiliation: 1: Osmania University
Abstract: Close binaries are ideal laboratories for studying physical phenomena such as chromospheric activity, mass transfer between component stars, distance estimation, etc. As these close binaries mostly are short periods, they play a vital role in explaining astrophysical phenomena such as mergers, their evolution, etc., that are not well understood in literature yet. Considering this, results of photometric and spectroscopic studies carried out by our group on few neglected close binaries will be presented. Their role in accurately determining the activity cycles and caused for period variations will be discussed.

18-Title: Multi-wavelength study of Active Galactic Nuclei with AstroSat
Author: Gulab Dewangan  1, @  
Affiliation: 1: IUCAA
Abstract: AstroSat is India's first multi-wavelength astronomy mission. It carries instruments suitable for observations in the UV, soft and hard X-rays for broadband spectroscopy and timing. AstroSat has observed a number of bright Active Galactic Nuclei (AGN) in the last five years. We have performed broadband spectroscopy of Seyfert type AGN in the near/far UV using UVIT/gratings, and X-rays using SXT and LAXPC. We have also studied the temporal connection between the UV and X-rays. These observations are helping us to probe the innermost accretion disk and its connection with the hot corona responsible for the X-ray emission. We will present insights gained with the AstroSat observations on the nature of accretion disks, the origin of soft X-ray excess, and the thermal Comptonisation process in AGN.

19-Title: Study of Low Frequency Radio Foregrounds using uGMRT  - Applications to Cosmological HI signal extraction
Author: Abirup  Datta 1, @  
Affiliation: 1: Indian Institution of Technology Indore
Abstract: In this talk, we present results from some recent observations with the uGMRT (SKA Pathfinder for India) at 300-500 MHz (Band 3) and 120 -240 MHz (Band 2). The target field that was observed is that of ELAIS-N1 (European Large-Area ISO Survey-North 1). For Band 3, the best RMS noise obtained is that of 12 uJy/beam (off-source). It should be noted that this is one of the best obtained with the uGMRT so far. We have used most of the state-of-the-art wide-field, wide-band direction-dependent calibration/imaging algorithms in CASA/SPAM for the data analysis. The final results are used to characterize the nature of foregrounds both in the spectral domain as well as spatial domain. The obtained dN/dS is then compared with the previous observations of the same field at these frequencies. These foregrounds pose a major challenge in the detection of the cosmological HI signal from the Pre-EoR (< 150 MHz)  and post-EoR (> 300 MHz) era. We present here our best estimate of the upper limit on the Post-EoR 21cm power spectrum. We will also present the initial results from the 21cm power spectrum estimation from Post-EoR epochs using the Artificial Neural Network. This has been very successful in our past Global 21cm signal studies.  Here, we present the recent application on the real observations.

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20-Title: Challenges of communication and outreach in the mega project- SKA
Author: William Garnier   1, @  
Affiliation: 1: SKA Communication office, UK
Abstract: This talk will present the challenges of communication and outreach in a global endeavor for the SKA megaproject, as well as the opportunities offered by having access to a large pool of talents within the community (communication professionals and the wider community of scientists and engineers) willing to communicate about the SKA and enthuse millions through outreach and education initiatives. This will provide the attendees the necessary information about the role they can play and the importance of connecting their activities to the existing initiatives and to the network we’ve established over time, both tapping into the resources available and developing new ones as well.

21-Title: Observing QSOs and their hosts with HARMONI on the Extremely Large Telescope
Author: B. Garcia-Lorenzo  1, @  
Affiliation: 1 : Instituto de Astrofisica de Canarias
Abstract: We

22-Title: Multi-wavelength spectroscopy to characterize multi-phase outflows and ascertain their feedback to host galaxies
Author: Aishwarya Girdhar  1, @  
Affiliation: 1: European Southern Observatory
Abstract: Spatially-resolved spectroscopy contains rich and crucial diagnostic information on how rapidly growing supermassive black holes, i.e., quasars, interact with their host galaxies. As part of our Quasar Feedback Survey of z<0.2 quasars, we have been using ESO/VIMOS and ESO/MUSE to spatially-resolve ionized gas kinematics and stellar kinematics in quasar host galaxies. Combined with multi-wavelength information we are assessing: (1) the properties of galactic multi-phase outflows driven by jets and/or winds; (2) what impact these have on the star formation properties of the host galaxies. In this talk I will give an overview of our survey, highlighting the crucial role of the multi-wavelength analysis. As a showcase, I will then present detailed observations of one target. We have used the unprecedented sensitivity of MUSE, to measure gas and the stellar kinematics, and isolated non-gravitational motion caused by the small-scale radio jet that is ploughing into the galaxy disk. We have further analyzed the prevalence of the molecular phase of the outflow by using the data from the interferometer ALMA. By combining the study of the ionized and molecular gas, to the stellar kinematics, we can begin to infer the feedback effects on the star formation in the host galaxy.

23-Title: The curious case of X-shaped radio galaxies: Back-flow model
Author: Gourab Giri  1, @, Bhargav Vaidya  2, @  
Affiliation: 1: Ph.D. scholar, 2: ASSISTANT PROFESSOR
Abstract: Extended radio galaxies show the presence of radio jets that are well-collimated plasma flows ranging up to Mpc scales. In some cases, we see significant distortion occurring in these large-scaled radio jets and resulting in X-shaped morphologies. They can be identified from the presence of two double-lobed jet structures aligned at an angle to each other (wing and active lobe). The back-flow model and the merger model have gathered some attention in describing these galaxies, besides the models which consider the presence of dual active galactic nuclei, jet precession, and even buoyancy. The goal of this work is to study the formation of X-shaped radio galaxies due to the back-flow model. In this regard, we have performed high-resolution axisymmetric simulations of jet propagation from triaxial galaxies and have shown the role of magnetic field strength and pressure gradient in shaping the extent of the secondary lobe (wing). Further, we have used state of the art Eulerian-Lagrangian framework to demonstrate the variation of spectral index and polarization in the radio band for these sources. The vital role of viewing orientation in determining the relative extent of primary and secondary lobe from synchrotron emission will be showcased using our 3D simulations along with its implications on the possibility of the existence of a universal formation mechanism of X-shaped sources.

24-Title: Probing early Galactic chemical enrichment of heavy elements with metal-poor stars
Author: Aruna Goswami  1, @  
Affiliation: Indian Institute of Astrophysics
Abstract:

25-Title: Circumstellar Disk Evolution in Cygnus OB2: A deep multi-wavelength study of a Galactic proto-globular cluster
Author: Saumya Gupta  1, @, Jessy Jose  2, @, Swagat Das  3, @, Surhud More  4, @, Manash Samal  5, @, Gregory Herczeg  6, @, Michihiro Takami  7, Satoko Takahashi  8, Tsuyoshi Terai  8, Zhen Guo  9, Katsuo Ogura  10  
Affiliation: 1: IISER Tirupati,2: Indian Institute of Science Education and Research Tirupati (IISER Tirupati), India, 3: IISER Tirupati, 4: IUCAA, Pune, 5: PRL, Ahmedabad, 6: KIAA/PKU 7: ASIAA, 8: NAOJ, 9: Univ. of Hertfordshire, 10: Kokugakuin University
Abstract: Circumstellar disk evolution plays a key role in the growth of stars and the formation of planetary systems. And yet it is one of the many interesting yet unanswered questions posed to the astrophysical community. Deep, large-scale studies of various star-forming regions are required to understand the effect of the cluster environment on disk evolution, their dispersal, and hence, on the planet formation. At 1.6 kpc distance from the Sun and with ~150 OB-stars, Cygnus OB2 is an ideal laboratory to study the role of a feedback-driven environment on disk evolution in one of the most massive regions outside the solar neighborhood. We have obtained the deepest and the widest optical photometry with 8m Subaru Hyper Supreme-Cam (HSC) of a 1.5? diameter region centered at Cygnus OB2. We combine our deep optical photometry with near-IR (UKIDSS) and mid-IR (Spitzer) photometry to study the pre-main sequence population (~105 sources) reaching down to brown-dwarf limit including a significant census of disk-bearing objects. We identify the circumstellar disk population in the target region and analyze the disk evolution as a function of age and mass by dividing the data into constant mass and age bins. We estimate the spatial variation of disk fraction across the region as a function of incident UV flux and thus quantify the role of external photoevaporation on disk evolution. We further aim to identify the sub-stellar population and obtain the IMF in the low-mass regime in one of the most massive regions outside the solar neighborhood.

26-Title: Upgraded GMRT as a SKA pathfinder facility
Author: Yashwant Gupta  1, @  
Affiliation: 1: NCRA-TIFR
Abstract: The Giant Metrewave Radio Telescope (GMRT), located near Pune in India, is a  major international facility at low radio frequencies, operational since 2002. The GMRT has recently completed a major upgrade that was targeted to improve its sensitivity by a factor of up to three and make it a much more versatile instrument. The goal was to provide (a) near-seamless frequency coverage from about 50 to 1500 MHz; (b) improved receiver systems with higher G/Tsys; (c) a maximum instantaneous bandwidth of 400 MHz; (d) a revamped servo system; (e) a sophisticated monitor and control system; and (f) matching improvements in infrastructure and computing. The full uGMRT, complete with all the receiver bands and the final version of the back-end was formally inaugurated and released to the global community in March  2019. Already, several exciting new results have been reported with the uGMRT,  and new frontiers of exploration are being opened. A wave of new discoveries is expected in the next few years. This paper will present details of how well the upgrade has worked, outline plans for further improvements, highlight the new science results that are coming out, and highlight the role of the uGMRT as a SKA pathfinder facility.

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27-Title: Deep uGMRT Band-3 observations of XMMLSS region
Author: Ishwara-Chandra C.H.  1, @  
Affiliation: 1: National Centre for Radio Astrophysics [Pune]
Abstract: Here we present the deepest ever image of the XMM-LSS region at 400 MHz with rms noise of ~10 microJy/beam at a resolution of ~6 arcseconds, using the upgraded GMRT (uGMRT) band-3 (250 - 500 MHz) observations. The field was observed with uGMRT band-3 for 25 hours using a bandwidth of 200 MHz with a band center of 400 MHz. The data were analyzed using a fully automated casa based pipeline. Additionally, direction-dependent corrections were applied. The final resulting image has an rms of about 10 microJy/beam at a resolution of about 6 arcseconds, making this the deepest image at this frequency range by any telescope. This rms is within a factor of three of the thermal noise. The source density is about 1800 sources per square degree. Several faint submJy sources have optical counterparts with photometric redshift larger than 1. Here we present the image, source catalog, optical counterparts of submJy sources, and other interesting individual science results. We will also discuss how such a deep, high-resolution image at 400 MHz is an excellent preview of science possibilities with SKA.

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28-Title: Study of the Blue Straggler Population in Galactic Open Clusters using Gaia
Author: Vikrant Jadhav  1, 2, @, Dr. Annapurni Subramaniam  3, @  
Affiliation: 1: Indian Institute of Astrophysics  2: Indian Institute of Science [Bangalore]  3: Indian Institute of Astrophysics  (IIA)  -  II Block, Koramangala, Bangalore 560 034 Karnataka -  India
Abstract: Blue stragglers are the most massive stars in clusters which are products of binary/multiple stellar interactions. They lie above the cluster turnoff due to their rejuvenated life. Due to this peculiar position in the color-magnitude diagram, proper motion membership is needed for their association to the cluster. We used Gaia DR2 astrometric and photometric data to identify and classify blue stragglers in open clusters. Approximately 2000 blue straggler members are identified in more than 300 open clusters with ages ranging from 100 Myr to 7 Gyr. 1500 other clusters within the same age range do not have any blue stragglers. Additionally, we have also created the first catalog of yellow stragglers, which are evolved from blue stragglers. A homogeneous catalog of blue and yellow stragglers can shed light on the binary evolution mechanisms in clusters with various age, density, binary fraction, and cluster environment.

29-Title: Long term investigations of short period contact binaries
Author: Rukmini Jagirdar  1, @  
Affiliation: 1: Osmania University, Hyderabad.
Abstract: The primary objective is to build a catalog of contact binaries with totality. Since, in the absence of spectroscopic observations, the photometric studies of totally eclipsing binaries provide reliable mass ratios 'q'. It is useful to carry out long term investigations of such totally eclipsing contact binaries and estimate the galactic distribution of their fundamental parameters. Period Variations, the presence of third bodies, the O'Connell effect, and other magnetic activities like flaring are prominent features in most of the contact binaries. There is a need to understand the relation between the same. The present work will discuss the above-mentioned points through the studies performed on data collected from the various ground and space-based observatories.

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30-Title: Estimation of Absolute Emission Altitude of Multi-component Pulsars
Author: Pavankumar Kadaladi  1, @  , R.t. Gangadhara  1, @  , Yashwant Gupta  2, @  
Affiliation: 1: Indian Institute of Astrophysics 2: National Centre for Radio Astrophysics [Pune]
Abstract: Single pulses from a pulsar are highly variable in shape, width, etc, but the average profile is stable. The average profile of a pulsar is a unique property of any given pulsar, making it the best way to characterize the emission geometry. The absolute radio emission height of pulse components is one of the crucial parameters needed in developing the radio emission mechanism. There are mainly two types of methods proposed for estimating the radio emission altitudes: (1) a purely geometric method, which assumes that the pulse edge is emitted from the last open field lines; (2) a relativistic phase shift method, which assumes that the asymmetry in the conal components phase location relative to the core is due to the aberration-retardation (A/R) phase shift. The component peak locations are determined by fitting gaussians to individual components, and the A/R phase shift of each component is estimated relative to the meridional plane. To estimate the absolute emission height of components including core, we have to estimate the phase shift of core and polarization position angle inflection point with respect to the meridional plane. Meridional plane is a fiducial plane containing a magnetic axis, rotation axis, and line of sight. Using the measured phase shift we can estimate the emission height of components in the pulsar magnetosphere. To estimate the emission height of pulse components, we chose a few multi-component pulsars and recorded single pulses using the uGMRT (upgraded GMRT). We have performed simultaneous dual-frequency (Band 3: 300-500 MHz and Band 4: 550-750 MHz) polarimetric observations. We plan to present the results obtained from the analysis of pulsars PSR B0950+08 and PSR B1133+16. We strongly feel that the estimation of radio emission heights will give an insight into understanding the pulsar radio emission mechanism.

31-Title: Galaxy clusters and superclusters: A Upgraded Giant Metrewave Radio Telescope View
Author: Ruta Kale  1, @  
Affiliation: 1: National Centre for Radio Astrophysics - Tata Institute of Fundamental Research  (NCRA)
Abstract: Galaxy clusters and superclusters are the densest environments in the Universe to study galaxy evolution and magnetization of the diffuse intra-cluster and inter-galactic media. Radio emission due to relativistic electrons and magnetic fields in the diffuse media are tracers of shocks and turbulent re-acceleration and that from the radio galaxies can trace gas motions and gentle re-acceleration. The Upgraded GMRT with wideband receivers is an ideal instrument for studying phenomena in galaxy clusters and superclusters. I will give an overview of our results regarding imaging of galaxy clusters and superclusters with the uGMRT. In addition, I will also briefly describe the online Radio Frequency Interference excision system aimed at improving the data quality that is being tested.

 

 

32-Title: Presence of third bodies in short period binary systems
Author: Sriram Kandulapati  1, @  , S Malu,
Affiliation: 1: Osmania University
Abstract: We present photometric studies of short-period binaries where possible third bodies are gravitationally bounded to the host binary systems. We observed these binary systems from JCBT (IIA), IGO (IUCAA), and to cover a long term time of minima, we used data from ASAS and K2 (Kepler satellite observations) databases. O-C studies indicate that the orbital period of these systems found to be increasing or decreasing and residual clearly showed a sinusoidal variation. Assuming that these variations are due to a third body, orbital elements were derived. We discuss such systems along with other detection from Kepler satellite observations which helps them to maintain the low angular momentum configuration. 

33-Title: Jets in Radio-Quiet AGN: A Close Look with the VLBA, VLA, and GMRT
Author: Preeti Kharb  1, @  
Affiliation: 1: National Centre for Radio Astrophysics - Tata Institute of Fundamental Research  (NCRA)
Abstract: In spite of their "radio-quiet" AGN classification, they appear to be "jetted" on both parsec and kiloparsec scales. I will present the results from VLBA, VLA, and GMRT observations of several samples of "radio-quiet" AGN, and attempt to place our results in the larger context of the radio-loud/radio-quiet divide in AGN.

34-Title: Is a new site for the i-process really needed?
Author: Drisya Karinkuzhi  1, 2, @, Sophie Van Eck 2, Stephane Goriely 2, Lionel Siess 2, Alain Jorissen 2
Affiliation: 1: Indian Institute of Science
2: Institute of Astronomy and Astrophysics, University of Brussels
Abstract: Among Carbon-Enhanced Metal-Poor (CEMP) stars, some are found to be enriched in s-process elements (called CEMP-s), some have over-abundance of r-process elements (CEMP-r), and some are characterized by both s- and r-process enrichment, and are then tagged CEMP-rs stars. Although the origin of peculiar abundance patterns in CEMP-s and CEMP-r stars are rather well-identified, the origin of the abundance pattern in CEMP-rs stars is still an open question. Also, the origin of the abundance differences between CEMP-s and CEMP-rs stars is presently unknown. It has been claimed that the i-process, whose site still remains to be identified, could better reproduce CEMP-rs abundances than the s-process. In our recent analysis of a sample of twenty-five CEMP stars (Karinkuzhi et al, 2021, arXiv: 2010.13620) we found that CEMP-rs stars can be explained as being polluted by a low-mass, low-metallicity thermally-pulsing Asymptotic Giant Branch (TP-AGB) companion experiencing i-process nucleosynthesis after proton ingestion during its first convective thermal pulses. We also propose a new classification scheme for CEMP stars based on eight heavy elements instead of the traditional classification based on only two elements Ba and Eu. Stars are re-classified into CEMP-s or -rs based on new classification and their abundance profiles are compared in detail. There seems to be an abundance continuum between the CEMP-s and CEMP-rs classes. Hence, we propose that they could be renamed as CEMP-sr stars since they represent a particular manifestation of the s-process at low-metallicities. For these objects, a call for an exotic i-process site may not necessarily be required anymore. In my talk, I will be discussing these new results as well as our future plans for the coming era of wide-field, large-aperture optical telescopes.

35-Title: The International Astronomical Union and its Offices
Author: Ajit Kembhavi
Affiliation: 1:IUCAA, Pune, India
Abstract: The traditional activities of the IAU have included the organization of a number of symposia every year,  a general assembly every three years year and carrying out responsibilities like the definition of fundamental astronomical and physical constants and assigning names to celestial bodies. Over the last decade, the IAU has set up four offices, the OAD, OAO,  OAE, and OYA which are responsibilities for activities like using astronomy for development, educating the young, and providing platforms for astronomy outreach. In my talk, I will describe the structure of the IAU and the activities carried out through the offices. I will also describe how engaging with the IAU can be enriching and rewarding at the individual, institutional and national levels.

36-Title: 3.6m DOT Facility and synergies with the theme of the event.
Author: Brijesh Kumar
Affiliation: 1: ARIES, Nainital, India
Abstract:

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37-Title: A study of classical radio galaxies at low radio frequencies
Author: Dharam Lal  1, @  , Tiziana Venturi, Bernie Fanaroff, Oleg Smirov, @
Affiliation: 1: National Centre for Radio Astrophysics [Pune]
Abstract: We use the low-frequency facilities, including the upgraded Giant Metrewave Radio Telescope to map classical radio galaxies. We present the deepest images made, reaching a few micro-Jy levels with unprecedented sensitivity and angular resolution at radio frequencies below 1.4 GHz. Our study is aimed to revisit the FR I and FR II classification of radio galaxies and we will also present detailed radio morphologies and their spectral structures.


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38-Title: The Milky Way and the MSE, post-2025
Author: Nicolas Martin 1, @

Abstract:

39-Title: Young stellar jets as non-thermal radio sources
Author: Alexandre Marcowith  1, @  
Affiliation: 1: Laboratoire Univers et particules de Montpellier  (LUPM)
CNRS: UMR5299, LUPM - UMR5299 Université de Montpellier - Campus Triolet Place Eugène Bataillon - CC 72 34095 Montpellier Cédex 05 FRANCE -  France
Abstract: Young stellar objects produce strong jets interacting with the surrounding interstellar matter. Some objects have already been detected at GHz wavelengths showing non-thermal spectra with inverted indices due to synchrotron radiation. These radiations are produced by relativistic electrons accelerated either along with the jet or at the jet termination shock. In this talk, I will discuss the status of young stellar jets as non-thermal emitters and then address the question of the physical mechanisms at the origin of the acceleration of the relativistic electrons. Finally, I will discuss the expected emission at other wavelengths.

40-Title: The future of massively multiplexed spectroscopy: the Maunakea Spectroscopic Explorer
Author: Jennifer Marshall  1, @  
Affiliation: 1: Maunakea Spectroscopic Explorer; Texas A&M University
Abstract: The Maunakea Spectroscopic Explorer (MSE) is a planned next-generation massively multiplexed spectroscopic survey facility that is completely dedicated to optical and near-Infrared spectroscopy of samples of thousands to millions of astrophysical objects at spectral resolutions from R~3,000 to R~40,000. With science goals spanning all of astrophysics, from detailed chemical abundance studies of nearby stars to investigating the cosmology of the early Universe, MSE will provide key science capabilities that will revolutionize the field. In this talk, I will review the current design status of the project and provide an overview of MSE's wide range of scientific capabilities.

41-Title: Detecting Lya emission in MUSE data cubes
Author: David Mary  1, @  
Affiliation: 1 : Université Côte d'Azur - Observatoire de la Côte d'Azur
Université Côte d'Azur (UCA), Observatoire de la Cote d'Azur
Abstract: This talk will review algorithms recently devised for detecting Lyman alpha emission in MUSE data cubes. Particular emphasis will be put on the difficult problem of estimating the true false alarm rate at which the detection tests are conducted.

42-Title: Management of diversity and inclusion in large international collaborations
Author: Simona Mei  1, @  
Affiliation: 1: LERMA -Observatory of Paris & IAU Coordinator for Management of Diversity and Inclusion in Large International Collaborations
Paris Observatory 77, avenue Denfert-Rochereau, Paris -  France
Abstract: The management of diversity and inclusion follows different approaches in large international collaborations. We discuss the different approaches and ethical suggestions for practices that enhance the respect of minorities and different cultural backgrounds in large international collaborations.

43-Title: Probing Pulsar Magnetosphere using time aligned Gamma-Ray and Radio Light Curves
Author: Dipanjan Mitra  1, @  , Jérôme Pétri  2, @  
Affiliation: 1 : National Centre for Radio Astrophysics [Pune] , 2 : Université de Strasbourg
Observatoire Astronomique de Strasbourg, Université de Strasbourg
Abstract: A highly magnetized and fast-spinning pulsar acts as a unipolar inductor, and as a result, the pulsar magnetosphere is filled with dense electron-positron pair plasma. Pulsars emit electromagnetic radiation which is observed as regular periodic pulses over a wide frequency range in radio, optical, X-ray, and gamma-rays. A major theoretical challenge is to understand how the pulsar unipolar induction model in conjunction with radiation physics can be applied to explain the observed broadband pulsed emission. In the last decade, our theoretical understanding of the formation of the pulsar magnetosphere has improved significantly thanks to numerical simulations. Further, since the launch of the Fermi Gamma-ray Observatory, a large sample of more than 250 gamma-ray pulsars have been discovered and high-quality radio observations of the radio-loud gamma-ray population have been obtained. In this talk, I will discuss how high-quality observations in radio and gamma-rays are being used to constrain pulsar radiation physics and the geometry of their magnetosphere.

44-Title: Low-z CIII absorber-galaxy connection
Author: Abhisek Mohapatra  1, @, Raghunathan Srianand  2, @  
Affiliation: 1: National Institute Of Technology, Rourkela  (NITR)  -  Website
Rourkela, Odisha, India-769008 -  India
2: Inter-University Centre for Astronomy and Astrophysics  (IUCAA)  -  Website
Post Bag #4, Ganeshkhind, S. P. Pune University Campus, Pune, Maharashtra 411007 -  India
Abstract: In this talk, I will present the detailed analysis of 99 optically thin C III absorption systems obtained from background quasar spectra at redshift, 0.2 < z < 0.9 associated with neutral hydrogen column densities in the range, 15< log N(H I) < (cm^−2 ) < 16.2. We search for associated galaxies within a projected distance of 1000 kpc around these absorbers. We find that at least 80 % of the absorbers are associated with one or more galaxies within 1000 kpc impact parameters. Using several available photometric observations of these galaxies, we construct the spectral energy distributions (SED) fitting algorithm to obtain several physical parameters such as photometric redshift, mass, star formation rate (SFR), star formation history (SFH). Furthermore, we analyze the dependence of CIII absorption on galaxy properties using different correlations between the derived properties. However, follow-up spectroscopic observations of these associated galaxies will be helpful to determine the precise redshift and constrain other properties.

45-Title: Far-infrared Spectroscopy of Galactic Photodissociation Regions
Author: Bhaswati Mookerjea  1, @, Goeran Sandell  2, Rolf Guesten  3  
Affiliation: 1: Tata Institute of Fundamental Research, 2: Institute for Astronomy, University of Hawaii, 3: Max Planck Institut fur Radioastronomie, Bonn
Abstract: Photodissociation Regions (PDRs) are regions where far-ultraviolet (FUV) radiation from young massive stars dominate the physics and the chemistry of the interstellar medium. The PDRs play an important role in reprocessing much of the energy from stars and re-emitting this energy in the infrared-millimeter regime. The [C II] line at 158 microns provides information about the kinematics of FUV irradiated gas and is one of the dominant cooling lines of gas for low to moderate densities and UV fields. The [O I] lines at 63 and 145-micron lines trace warm and high-density gas, excited in photodissociation regions with a strong UV field or by shocks. In this talk, I will describe the results of our recent observations of a few Galactic PDRs with the GREAT receiver onboard SOFIA. These observations have revealed that the [C II] line primarily assumed to be optically thin is mostly optically thick and detailed velocity analysis of [O I] lines have revealed large columns of PDR gas otherwise not detected in any other tracers.

46-Title: Multi-scale feedback from relativistic jets by supermassive black holes
Author: Dipanjan Mukherjee  1, @  
Affiliation: 1: Inter-University Centre for Astronomy and Astrophysics [Pune]
Abstract: Relativistic jets from AGNs are an important driver of feedback in galaxies with an active black hole. They impact the nearby environment over different physical scales during their lifetime, with varying effects. They first interact with the host galaxy's ISM before breaking out to larger scales, significantly affecting the galaxy's morphology and evolution. I shall present the results of our recent 3D relativistic (magneto) hydrodynamic simulations, performed on scales of several kpc, of AGN jets interacting with the ambient ISM and CGM. The young relativistic jets initially couple strongly with the turbulent ISM, driving fast-moving lateral outflows of dense gas. We have performed a suite of simulations of different jet powers, ISM conditions, and morphologies. While AGN activity can potentially quench star formation by driving outflows or inducing turbulence, we find that they can also potentially enhance star formation (positive feedback) in localized patches. I will discuss the observational signatures of such jet-ISM interactions predicted by our simulations (optical+radio) which will help constrain the models from observed results.

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47-Title: Observational Aspects of Triggered Star Formation in the Milky Way
Author: Devendra Ojha  1, @  
Affiliation: 1 : Tata Institute of Fundamental Research  (TIFR)  -  Website
Homi Bhabha Road, Mumbai 400005 - India -  India
Abstract: Since the last few years we are pursuing multiwavelength (optical, infrared, sub-mm, mm, and radio) studies of Galactic star-forming regions. The use of multiwavelength data is essential to investigate the ionized, neutral, and molecular components of the gas, the dust, and the population of young stellar objects. A variety of Galactic H II regions (bright, faint, smaller, nearby, and distant) have been explored. Evidence of direct interactions between the H II regions, molecular gas, and the young stellar objects has been found on large and small scales. In this talk, I will present the recent results from our ongoing investigation of triggered star formation at the periphery Galactic H II regions. In the second part of my talk, I will give a brief description of the activities of the Infrared Astronomy Group (DAA) of TIFR with special emphasis on the ground-based Near-Infrared and balloon-borne Instrumentation for star formation studies. The unique design of TIRSPEC (on 2-m HCT telescope at Hanle, Ladakh) currently being heavily used by the astronomy community, and also the upcoming TANSPEC, which is being built for India's largest 3.6-m Devasthal Observatory Telescope (DOT), will be presented. The unique capability of TIRCAM2 (on 3.6-m DOT), for observations in the PAH (λcen ~ 3.3 µm) and nbL (λcen ~ 3.59 µm) bands will also be presented.

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48-Title: Measuring hydrogen-to-helium ratio from stars
Author: Gajendra Pandey  1, @  
Affiliation: 1: Indian Institute of Astrophysics
Abstract: The H/He ratio of the universe comes from the measurements made using B-type stars. This ratio is assumed to be the same across all-stars, both hot and cool, for a fine abundance analysis. In this talk, I shall discuss the measurement of the H/He ratio from the optical spectra of cool stars that do not have the helium line transition in their photospheres.

49-Title: Radio and multiwavelength survey of Galaxy clusters
Author: Mamta Pandey-Pommier  1, @  
Affiliation: 1: University Claude Bernard Lyon1, Lyon, France
Abstract: Merging galaxy clusters show evidence of violent matter and gas interaction in the form of turbulent radio halos and the rapid evolution of galaxies in their extremely dense environments. We carried out low-frequency radio observations with the GMRT and LOFAR on a sample of galaxy clusters, to study the non-thermal emission from the intra-cluster medium and the impact of the merger on the intracluster gas and galaxy population within the cluster environment. In this talk, we present our results on the rare diffuse radio emission discovered in the cluster center from our sample. Using multi-wavelength (radio/optical/IR/X-ray) data, we conclude that the dynamically unrelaxed central region of the merging cluster has on-going minor merging activity that gives rise to a steep spectrum halo emission tracing different merger stages of the cluster.

50-Title: Career challenges faced by women in Astronomy
Author: Mamta Pandey-Pommier  1, @  
Affiliation: 1: University Claude Bernard Lyon1, Lyon, France
Abstract: I will present the statistics, challenges, and different career graphs for Women in Astronomy and STEM and examine how these graphs evolve in different (personal responsibility) situations. I will also highlight the need to support women's careers in higher academics and describe the SFC-UDL initiative started at the University Claude Bernard Lyon1, France.

51-Title: Spectroscopy of Interstellar Aromatics
Author: Amit Pathak  1, @  
Affiliation: 1: Department of Physics, Banaras Hindu University
Abstract: Aromatics are mostly single or fused Benzene rings that are highly stable due to the delocalized electrons. These compounds are quite common in terrestrial environments and are formed by the burning of hydrocarbons (viz. vehicle exhausts, smokes, etc.). Here we will be focusing on aromatics, specifically Polycycylic Aromatic Hydrocarbon (PAH) molecules that are expected to be present in interstellar space and are inherently involved with the chemistry of the local environment. Polycyclic aromatic hydrocarbon (PAH) molecules are predominant in various interstellar environments and are detected by the observation of strong emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 μm not only in the Milky Way but also in external galaxies[1]. Confirmation of the presence of fullerene cation in the interstellar medium (ISM)[2] strongly supports the presence of PAHs. In the harsh interstellar conditions, PAHs experience physical and chemical processing that brings changes in the molecule. Ionization, dehydrogenation, etc. produce significant spectral signatures that are being diagnosed spectroscopically.
We have been studying variants of PAHs, viz., deuterated[3], dehydrogenated[4], and also with the addition of aliphatic side groups[5]. Density functional theory (DFT) has been used to calculate the theoretical vibrational spectra of PAHs. The spectra obtained matches well with available experimental spectra and provide important clues to the form of PAHs present in the ISM.
We explore the probable formation mechanisms and spectral signatures of PAH variants that may be related to the existence of deuterated PAHs, PAH anions, and PAHs with aliphatic side groups. Unique spectral characteristics of these PAHs are discussed. Our results have enormous implications in establishing the existence of these large aromatics in space.
References
1. Tielens A.G.G.M., 2008, ARA&A, 46, 289
2. Campbell et al., 2015, Nature, 523, 322
3. Buragohain et al., 2015, MNRAS, 454, 193
4. Buragohain et al., 2018, MNRAS, 474, 4594
5. Buragohain et al., 2020, ApJ, 892, 11

52-Title: Testing Dense Gas Star Formation Relations in the Outer Milky Way
Author: Sudeshna Patra  1, @, Neal Evans  2, Jessy Jose  1, Kee-Tae Kim  3, Mark Heyer  4, Swagat Das  1, Jens Kauffmann  5, Manash Samal  6  
Affiliation: 1: Indian Institute of Science Education and Research, Tirupati, 2: The University of Texas at Austin, 3: Korea Astronomy and Space Science Institute, 4: Department of Astronomy, University of Massachusetts Amherst, 5: Haystack Observatory MIT, 6: Astronomy & Astrophysics Division, Physical Research Laboratory
Abstract: Studying star formation in the outer part of the Milky Way (galactocentric radius > 8.5 kpc) is an excellent way to study the early phase of galaxy evolution and properties of dwarf galaxies in a zoomed way since the environmental conditions are similar. The Milky way gives the best landscape to study the effects of low metallicity and low gas surface density in star formation as it has a metallicity gradient, which decreases with increasing Galactocentric distance. We are leading a large scale observational survey of star-forming regions in the outer Milky Way intending to understand the role of environmental conditions (such as metallicity and Galactocentric distance) on the outcome of the star formation process such as star formation rate (SFR), star formation efficiency (SFE), initial mass function (IMF), etc. We present the results obtained from the analysis of dense molecular line tracers (HCN (1-0) and HCO+(1-0)) along with other tracers like millimeter continuum emission (1.1 mm), extinction derived from 13CO, and dust continuum data from Herschel for star-forming regions located in the outer Galaxy, with a broad science goal to understand the star formation activities in them.

53-Title: High Redshift Obscured Quasars and the Need for Optical to NIR, Massively Multiplexed, Spectroscopic Facilities

Author: Andreea Petric  1, @  
Affiliation: 1: STScI INS Roman Branch
Abstract: Most bulge-dominated galaxies host black holes with masses that tightly correlate with the masses of their bulges. This may indicate that the black holes may regulate galaxy growth or vice versa, or that they may grow in lock-step. The quest to understand how, when, and where those black-holes formed motivates much of extragalactic astronomy. Here we focus on a population of galaxies with active black holes in their nuclei (active galactic nuclei or AGN), that are fully or partially hidden by dust and gas: the emission from the broad line region is either completely or partially obscured with a visual extinction of 1 or above. This limit, though not yet precise, appears to be the point at which the populations of AGN may evolve differently. We highlight the importance of finding and studying those dusty AGN at redshifts between 1 and 3, the epoch when the universe may have gone through its most dramatic changes. We emphasize the need for future large multiplexed spectroscopic instruments that can perform dedicated surveys in the optical and NIR to pin down the demographics of such objects and study their reddening properties, star-formation histories, and excitation conditions. These key studies will shed light on the role of black holes in galaxy evolution during the epoch of peak growth activity.

54-Title: The Gender Gap project: results and recommendations
Author: Francesca Primas  1, @  
Affiliation: 1: European Southern Observatory & IAU Women in Astronomy Chair
Abstract: The International Astronomical Union is one of the main partners of the project “A Global Approach to the Gender Gap in Mathematical and Natural Sciences: How to Measure It, How to Reduce It?”, an interdisciplinary collaboration of eleven partners (mostly professional unions), led by the International Mathematical Union and the International Union of Pure and Applied Chemistry. During the triennium 2017-2019, the project was supported by the International Science Council. The project aims to better understand the problems mathematical, computing, and natural science academics and practitioners are facing around the world. In this talk, I will present the main findings and final recommendations of the project, highlighting some of the figures that have emerged for the field of Astronomy from the Joint Global Survey that was carried out in 2018.


55-Title: Gender Equity in Academia: how to be a male ally?
Author: Manoj Puravankara  1, @  
Affiliation:  Tata Institute of Fundamental Research, Mumbai, IND
Abstract: Gender equity in academia is relational, so it is not just a women's issue. Men have to be equal stakeholders in the efforts towards gender equity. I will briefly talk about how men can be effective allies for promoting gender equity in academia.

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56-Title: WALOP/PASIPHAE: A unique tomographic survey of Galactic dust and magnetic fields
Author: Anamparambu Ramaprakash  1, 2, 3, @, Konstantinos Tassis, Siddharth Maharana, John Kypriotakis, Dmitry Blinov, Georgia V. Panopoulou, Ramya Anche, Shrish Shrish, Tuhin Ghosh, Hans Kristian Eriksen, Eirik Gjerløw, Sebastian Kiehlmann, Nikolaos Mandarakas, Vasiliki Pavlidou, Timothy J. Pearson, Vincent Pelgrims, Stephen B. Potter, Anthony C. S. Readhead, Raphael Skalidis, Ingunn K. Wehus,
Affiliation: Inter-University Centre for Astronomy & Astrophysics (IUCAA), 2: Institute of Astrophysics, Foundation for Research and Technology-Hellas, 3: Cahill Center for Astronomy and Astrophysics, California Institute of Technology
Abstract: Galactic magnetic fields permeating through dust clouds lead to the partial alignment of non-spherical dust grains along the field lines. Starlight passing through these dust clouds gets partially linearly polarized due to selective extinction. Measuring this polarization offers in principle, a way of tracing the magnetic fields as well as probing the nature of the dust grains. Dust induced polarization also creates a foreground smokescreen which makes it very difficult to measure underlying tiny signals such as that of B-mode polarization of CMBR. Removing this foreground is not easy for many reasons. For example, along any given line of sight, there will be several dust clouds (two to three even along high Galactic latitude sightlines), each with possibly different grain compositions, magnetic field strengths, and orientations. Due to vector addition effects, the net measured polarization may often not trace the polarization or magnetic fields in any of the individual dust clouds. We plan to carry out a linear optical polarimetric survey (PASIPHAE: Polar-Areas Stellar Imaging in Polarization High-Accuracy Experiment) of specifically chosen high Galactic latitude areas with an unprecedented combination of depth (R<16.5), swath (> 1000 sq. degrees), and faith (error<0.1%). Two bespoke instruments (WALOP: Wide Area Linear Optical Polarimeter) will be used to carry out the survey simultaneously from a northern (Skinakas) and a southern (Sutherland) site. The high sample density (>100 stars per sq. degree), large area coverage of PASIPHAE measurements (> 10000 sq. degrees), and low noise (0.1% for R>15 stars) augmented with data on stellar distances from GAIA and dust cloud distributions from CO maps, will allow us to create a tomographic map of the magnetic field structure towards the survey regions. This talk presents the salient challenges of WALOP/PASIPHAE as well as the results from some path-finding experiments.

57-Title: Li in stars 
Author: B. Eswar Reddy  1, @  
Affiliation: 1: Indian Institute of Astrophysics, IND
Abstract:

58-Title: A Blue MUSE for the VLT
Author: Johan Richard  1, @  
Affiliation: 1: Centre de Recherche Astrophysique de Lyon  (CRAL) 
Abstract: I will present the concept and science prospects of BlueMUSE, an optical seeing-limited, blue-optimized, medium spectral resolution, panoramic integral-field-spectrograph under development for the VLT. The project is an evolution of the technology used on the very successful VLT / MUSE instrument, with a similar architecture and many similar systems, but with a new and distinct science case enabled by its main characteristics: (1) a wavelength coverage 350 – 580 nm, (2) an average spectral resolution R=4000 (3) up to 2 arcmin2 field-of-view. BlueMUSE will offer new and unique science opportunities in many fields of astrophysics, beyond those possible with MUSE. Among the science goals available with this new instrument, it will survey a large sample of massive stars in our galaxy and the Local Group, study ionized nebulae, starburst, and low surface brightness galaxies. At high redshift, it would allow us for the first time to detect the IGM unambiguously in emission, as well as study the evolution of the CGM properties near the peak of the Cosmic Star formation history. There are strong synergies with BlueMUSE and future instruments/facilities in 2030, in particular JWST, the ELT, SKA, and Athena.


59-Title: Low Radio Frequency Observations of Supernova Remnants: what can we learn?
Author: Nirupam Roy  1, @  
Affiliation: 1: Indian Institute of Science [Bangalore]
Abstract: The interstellar medium, from which the new stars are born and to which the old stars inject matter and energy thereby enriching it, is indeed an integral and important component of the galaxies. Supernovae and Supernova Remnants play a major role in shaping the properties and evolution of the interstellar medium. In this talk, I will present results on low radio frequency view of supernova remnants, and discuss how (u)GMRT can play a role in a census of supernova remnants. These in turn will address some key questions not only related to supernova remnants but also regarding the interstellar medium and star formation.

60-Title: Low radio frequency observations of nearby galaxies
Author: Subhashis Roy  1, @, Souvik Manna  1, @  
Affiliation: 1: National Centre for Radio Astrophysics [Pune]
Abstract: We have observed a set of seven nearby large angular sized galaxies at 0.33 GHz using GMRT with an angular resolution of ~15''  and sub-mJy sensitivity. Using archival VLA data at 1.4 GHz, we determined their spatially resolved spectrum. The spectral indices are comparatively flat at the galaxy centers and gradually steepens with increasing galactocentric distances. Using archival far-infrared (FIR) MIPS 70 micron data we estimate the slope of the radio-FIR correlation. The slope from the 90 cm (0.33 GHz) data was around 0.74 +/- 0.03 and is significantly flatter than the slope 0.89+/-0.03 obtained using 20cm (1.4 GHz) data. This indicates cosmic-ray electron (CRe) propagation to have reduced the correlation between FIR and 0.33 GHz radio. Assuming simple isotropic diffusion of CRe, we find that for most of the galaxies there is a significant departure from this simple model, and more realistic models are necessary to understand the results. Equipartition magnetic fields as a function of galactocentric distance show a slow decline with increasing distance and drops by ~2-5 near the periphery of the galaxies. We also study the correlation of magnetic fields with star formation rates in these galaxies. We are also processing GMRT meter wavelength data of another 17 galaxies. Some preliminary results from these observations will also be presented.

61-Title: First stars with the SKA and its pathfinders
Author: Tirthankar Roy Choudhury  1, @  
Affiliation: 1 : National Centre for Radio Astrophysics  (NCRA)  -  Website
Pune University Campus, Ganeshkhind, Pune, Maharashtra - 411007, India; -  India
Abstract: The talk will focus on the efforts of detecting the signatures of the first stars with SKA pathfinders and precursors.

62-Title: Radio Emission from Pulsars due to Relativistic Plasma
Author: Tridib Roy 1, @   R.T. Gangadhara
Affiliation: 1: Indian Institute of Astrophysics
Abstract: The pulsar radio emission is not well understood because of a lack of knowledge about the emission geometry and the plasma process involved. We develop a mechanism for pulsar radio emission that takes into account the detailed viewing geometry of pulsars and the dipolar magnetic field configuration. Using suitably chosen geometry and plasma parameters, we derive analytical expressions for the Stokes parameters of the radiation field in the frame centered on the neutron star. We have simulated pulse profiles based on our analytical formulation. It seems that we can explain the enhanced radiation and most of the diverse polarization properties of radio pulsars. We have estimated the brightness temperature, which seems to agree with the observations. The polarization angle predicted by the model is in good agreement with the rotating vector model.

63-Title: CEFIPRA Organization
Author: Purnima Rupal 1, @  
Affiliation: 1:Indo-French Centre for the Promotion of Advanced Research (IFCPAR/CEFIPRA)
New Delhi -India
Abstract: Indo-French Centre for the Promotion of Advanced Research

64-Title: Women's careers in research between France and India
Author: Women scientific officers of CEFIPRA  1, @  
Affiliation: 1:Indo-French Centre for the Promotion of Advanced Research (IFCPAR/CEFIPRA)
New Delhi -India
Abstract: Indo-French Centre for the Promotion of Advanced Research

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65-Title: Insights into the structure of molecular clouds and star formation within them with the study of bipolar HII regions
Author: Manash Samal  1, @  , Annie Zavagno  2, 3, @  
Affiliation: 1: PHYSICAL RESEARCH LABORATORY  (PRL) Ahmedabad -  India, 2: Laboratoire d'Astrophysique de Marseille (LAM), Marseille CNRS : UMR7326, Aix-Marseille Université - AMU, INSU, 3 : Institut Universitaire de France, CNRS : UMR7326, Aix-Marseille Université - AMU, INSU
Abstract: Interstellar sheets and filaments play a central role in the star formation process, including the formation of massive stars. Once a massive star forms, it photoionizes its surroundings, forming an ionized (HII ) region. Our understanding of the evolution and physics of HII regions comes mostly from studies that assume the spherical symmetry of molecular clouds. Classical HII regions also show bipolar morphologies. The formation and evolution of spherical or blister HII regions have been relatively well-studied. To date, little numerical work has been devoted to the modeling and simulation of bipolar HII regions, primarily because no adequate attention has been paid to the identification and characterization of such nebulae. We have identified and investigated 16 bipolar HII regions in a zone of the Galactic plane between ±60° in longitude and ±1° in latitude using Spitzer, Herschel, JCMT, and APEX observations. In this talk, I shall discuss the structure of the star-forming clouds based on the detected bipolar HII regions, roles of filaments and sheets in the formation and evolution of such regions, and the impact of bipolar HII regions on the subsequent star formation processes of the parental cloud.

66-Title: Identification of Four Miscellaneous Radio Sources from LoTSS DR1
Author: Tapan Sasmal  1, @  , Soumen Bera  1  , Sabyasachi Pal  2  , Soumen Mondal  1  
Affiliation: 1: Jadavpur University, 2: Midnapore City College
Abstract: We undertook a search for Miscellaneous Radio Galaxies (MRGs) by using Low- Frequency Array (LOFAR) telescope at 144 MHz frequency. The morphological structures of MRGs are different from known structures. We are interested to study these types of sources because of their unique and peculiar morphology. Here, we report four MRGs from LOFAR Two Metre Sky Survey first data release (LoTSS DR1) which covers a 424 square degree region. The MRSs are identified by manual visual search (MVS) from the LoTSS DR1 data catalog. We also check their radio morphology from other surveys like VLA Faint Images of the Radio Sky at Twenty-Centimeters (VLA FIRST) and Westerbork Northern Sky Survey (WENSS) at 1400 MHz and 325 MHz frequencies, respectively. Based on optical counterparts from Sloan Digital Sky Survey (SDSS), we have estimated different physical parameters like spectral index, radio luminosity, radio power of these MRGs. We also try to find out the associate galaxy clusters corresponding to these MRGs.

67-Title: Multi-wavelength studies of star-forming regions
Author: Saurabh Sharma1, @ 
Affiliation: 1: Aryabhatta Research Institute of Observational Sciences
Abstract: Understanding the formation process of stars and their evolution constitute one of the basic problems in astrophysical research. Star-forming regions present a unique laboratory for understanding the process of star formation, the Initial Mass Function (IMF), the early evolution of stars over a wide mass range, and the nature of interactions between young stars and their surrounding interstellar medium. Various efforts have been already made to study these regions but the satisfactory explanation of the star formation process is still far from reality. Availability of good quality multi-wavelength data from various telescopes/instruments provides an excellent opportunity to study in detail the physical process going on in these regions which will be very helpful to constrain various star formation scenarios. In this talk, I will be presenting the results of our study related to star formation in several star-forming regions.

68-Title: Understanding how Supermassive Black Holes Drive Galaxy Evolution Using Future Eyes
Author: Prajval Shastri 1, @ 
Affiliation: 1: ICTS, IND
Abstract: The well-established scaling relationships of the central supermassive black holes of galaxies that persist across cosmic time will be discussed. These scaling relationships can be understood if star formation in the host galaxies of these black holes is regulated by feedback from accretion processes around the central supermassive black hole. However, the exact nature of this feedback, the relationship with jet launch, the connection with galaxy mergers and harassment, and how these phenomena evolve to z~0 is poorly understood. An overview of current evidence, including our own results from a multi-frequency investigation of the circum-nuclear environments of a sample of nearby southern active galaxies will be presented. The gaps in our understanding that can be addressed by upcoming facilities will be discussed.

69-Title: Gender equality
Author: Prajval Shastri 1, @ 
Affiliation: 1: ICTS, IND
Abstract:

70-Title: Low-surface brightness, dwarf galaxies?
Author: Sethuram Ramya 1, @ 
Affiliation: 1: Indian Institute of Astrophysics
Abstract:

71-Title: High Latitude Galactic star clusters with EDR3
Author: Priya Shah (Hassan)  1, @  
Affiliation: 1: Maulana Azad National Urdu University, Hyderabad, India
Abstract: The discovery of high latitude star clusters with WISE data is very crucial to our understanding of the galactic halo. We study a sample of 9 such clusters reported in the literature using Gaia EDR3. We find that some of these clusters most likely exist, while some are not confirmed. We also use GALEX data to confirm their youth and estimate their parameters. The implications and the physical processes possible to explain their existence are also discussed.

72-Title: The proposed optical-UV space mission - Indian Spectroscopic and Imaging Space Telescope (INSIST)
Author: Annapurni Subramanian 1, @  INSIST team
Affiliation: Indian Institute of Astrophysics
Abstract: Combining a large focal area with a simple and efficient optical design, INSIST is a UV-optical 1m class telescope expected to produce HST-quality imaging and moderate resolution spectra of astronomical sources. The main science drivers for this mission span a wide range of topics, starting from the evolution of galaxies in groups and clusters, chemo-dynamics and demographics of the nearby universe, stellar systems with accretions, to stars with planetary systems, to cosmology near and far. INSIST is in the pre-project phase where a few critical sub-systems are being demonstrated. The Canadian CASTOR mission has similar features and discussions are maturing to make a collaborative mission with the Canadian team.

73-Title: Multi-wavelength view of the assembly process of dwarf galaxies
Author: Smitha Subramanian 1, @ 
Affiliation: Indian Institute of Astrophysics
Abstract:

74-Title: A multiwavelength investigation of the circum-nuclear environment of nearby AGNs
Author: M N Sundar, 1 @, Prajval Shastri, Lalita Sairam, P T Rahna, Brent Groves, Jayant Murthy, Preeti Kharb, John Hutchings, S7 team
Affiliation: Jain (Deemed-to-be-University)
Abstract: The supermassive black hole scaling relationships suggest a strong connection between the accreting supermassive black holes at the centers of galaxies and their host galaxies through feedback mechanisms. We investigate the hallmarks of these processes in the nuclear regions of the host galaxies by studying about 130 nearby active galaxies (Siding Spring Southern Seyfert Spectroscopic Snap-Shot Survey (S7)) including IFU observations and multi-wavelength follow-ups of a subset of the objects. We present our most recent results based on the multi-frequency data, including observations of a supermassive binary black hole precursor.

75-Title: Exploring the possibility of identifying Branched Chain Molecules
Author: Satyam Srivastav  1, @  , Amit Pathak, @
Affiliation: 1 : Satyam Srivastav
Abstract: Interstellar detection of the straight-chain (n-propyl cyanide) and branched-chain (isopropyl cyanide)molecules toward the star-forming region, Sgr B2(N2) has attracted attention to study the formation mechanism and chemical evolution. Branched-chain molecules are the precursors of biologically relevant prebiotic molecules, i.e., amino acids. In this light, we consider n-butyl cyanide and higher-order branched chain molecule, t-butyl cyanide from the C5H9N isomeric group. We employ the gas-grain chemical model to study the chemical evolution of these species. We predict new formation and destruction pathways which could lead to more insight into the formation and destruction schemes of complex organic branched molecules in space. Quantum chemical calculations such as binding energy, enthalpy of formation, reaction enthalpies, activation barrier, dipole moments, and other spectroscopic information assist to study the chemical abundance and examine the possibility of detecting higher-order branched-chain molecules in high-mass star-forming regions.


76-Title: Studying giant low surface brightness galaxies like Malin 1 with current and future spectroscopic facilities
Author: Junais Snc  1, @  , Samuel Boissier  2, @  
Affiliation: 1 : Laboratoire d'Astrophysique de Marseille Aix Marseille Université : UMR7326 2 : Laboratoire d'Astrophysique de Marseille  (LAM)  -  Website
INSU, CNRS : UMR7326, Aix Marseille Université
Pôle de l'Étoile Site de Château-Gombert 38, rue Frédéric Joliot-Curie 13388 Marseille cedex 13 -  France
Abstract: Low Surface Brightness galaxies (LSBs) represent a significant fraction of galaxies in the nearby universe (up to 50% according to O'Neil & Bothun 2000; 40% for Galaz et al. 2011).  Despite this large fraction, the structure and origin of this class of galaxies is still poorly understood, especially due to their exceedingly low surface brightness, hindering high-resolution kinematics and spectroscopy. Malin 1 is the largest known low surface brightness galaxy to date, the archetype of so-called giant LSBs (GLSBs), with a disk diameter above 200 kpc. It is also similar to the galaxies with an eXtended Ultra Violet (XUV) disk found in ∼30% of nearby galaxies (Thilker et al. 2007). This class of galaxies with huge diffuse LSB disks are perfect laboratories for the study star formation in a low density regime. I will present a recent work (Junais et al. 2020) in which we use long-slit spectroscopy of Malin 1 to put new constraints on the inner rise of its rotation curve and to estimate the star formation surface density in the largest existing star-forming disk. I will also discuss about a recently assembled sample of HI and UV selected GLSBs, for followup spectroscopic and photometric observations. Similar studies as discussed above for the case of Malin 1 will be extended to this larger sample of GLSBs. This will enable us to study the nature and formation of galaxies like Malin 1 and other GLSBs/XUVs in general, which is still debated. Future facilities with large FOV IFU (such as BlueMUSE) will be of paramount importance to survey GLSBs and similar galaxies (such as XUV extended disks).

77-Title: Supernovae remnants with Astrosat.
Author: Firoza Sutaria  1, @  
Affiliation: 1: Indian Institute of Astrophysics
Abstract: Results from our Astrosat program to do a soft x-ray and UV study of segments of nearby, x-ray and UV-bright, supernova remnants, all in late time expansion phase, will be presented. We interpret our results in combination with archival radio and optical data and explore the scientific potential of observing these and similar supernovae remnants with the SKA and MSE.

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78-Title: The prospects, possibilities and science opportunities for a mm/sub-mm observatory in the Himalayas
Author: Janani Varadhachari a , Sriram S, Gajendra Pandey, G.C.Anupama, Kei Szeto b , Eric Williams b
Affiliation: 1:Center for Astrophysics | Harvard & Smithsonian, US
Abstract:

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79-Title: Primary Mirror Error Budget Development for Mauna Kea
Author: Janani Varadhachari, Sriram S, Gajendra Pandey, G.C.Anupama, Kei Szeto, Eric Williams
Affiliation: 1:Indian Institute of Astrophysics, Bangalore, India, CFHT Corporation, 65-1238 Mamalahoa Hwy, Kamuela, Hawaii 96743, USA
Abstract: The Mauna Kea Spectroscopic Explorer (MSE) is a planned 10meter class telescope and is optically designed as a prime focus telescope with hyperbolic primary of 60 segments of size 1.44m, delivering a circumscribed 11.25 meter aperture, and with a five element wide field corrector providing 1.5 square degrees of corrected field of view at the prime focus. Each segment in the primary mirror (M1) is an off-axis, non axial symmetric hyperbolic in shape. In ideal case, all the 60 segments together need to form a monolithic shape of M1. Each segments profile, at its position, needs to be matched with the monolithic profile. The deviation from the monolithic shape of M1 will degrade the image quality. The possible error contribution from M1 is identified and categorized into seven major groups. Error contribution from components under each group has been studied and error budget for primary mirror has been generated. 80% Encircled Energy (EE80) metrics has been used for generating the Primary mirror (M1) error budget. The budgetary estimation will serve as the basis for defining the tolerance, making trades between the performance, budget and schedule, and as a statistical estimate of the expected performance of the telescope. Here we present the details about the technique used for the development of the mirror segment error budget with the deal Wide Field Corrector (WFC) on the MSE system.

80-Title: DFT study of interstellar fullerenes and hydrogenated derivatives
Author: Akant Vats  1, @, Amit Pathak  1, @  
Affiliation: 1: Banaras Hindu University
Abstract: The presence of fullerenes in the interstellar medium (ISM) has been confirmed after the identification of two diffuse interstellar bands (DIBs) with C_{60}^+. Fullerenes are reactive with hydrogen that hints at the existence of hydrogenated fullerenes to be feasible in space (Cataldo & Iglesias-Groth 2010a). We present the theoretical study of fullerenes and it's hydrogenated derivatives, and discuss the astrophysical implications.

81-Title: A new method for determining the parameters of close double systems of supermassive black holes
Author: Alexandr Volvach  1, @, L. N. Volvach, M.G. Larionov
Affiliation: 1: Crimean Astrophysical Observatory, Crimea, Europe
Abstract: We propose a new method for calculating the parameters of the orbits of double supermassive black holes (SMBH) using only multi-frequency monitoring data in the radio band. Our results suggest that 3C 454.3 may be the most massive close double system of SMBHs. The shape of the flux density change during the unusual flare in 2014-2020 may indicate the coincidence of planes of the accretion disk (AD) and the orbits of the companions. We use a novel combination of data monitoring studies in the radio range and a new method for determining system parameters to obtain estimates of the diameter and thickness of AD 3C 454. According to our study, due to precession, companions will leave the central parts of the AD in a few years if the AD
retains its stability and does not collapse before that time. Estimates of the values of changes in the orbits of 3C 454.3 companions are made. The obtained values of changes in the orbits do not allow them to be detected by modern methods. The calculated lifetimes of the 3C 454.3 systems show that this is a short-lived object in the Universe with a lifetime of 5*10^4 yr.  

Reference: A.E Volvach, L. N. Volvach, M.G. Larionov, 2021 A&A, in press, DOI: https://doi.org/10.1051/0004-6361/202039124

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82-Title: On the interdependence of morphology, kinematics, environment, and star-formation in galaxies in the nearby Universe
Author: Yogesh Wadadekar,   1, @
Affiliation:
Abstract: By combining multiwavelength data, from ultraviolet, optical, near-infrared, and mid-infrared bands with recently obtained integral field spectroscopy, we are able to study the dependence of star formation on morphology, environment, and stellar/gas kinematics. It has now become possible to carry out such studies with samples of thousands of galaxies, for the first time, thanks to the availability of sensitive, large area broadband surveys and integral field observations with the SDSS MaNGA survey. I will highlight the main results of our work, and discuss how the mapping of neutral hydrogen in galaxies with radio telescopes will help complete the picture of how, when, and where gas gets converted to stars in galaxies in the nearby Universe.

83-Title: Extragalactic Surveys with the Square Kilometre Array
Author: Jeff Wagg  1, @  
Affiliation: 1: Square Kilometre Array Organisation  (SKAO)
Abstract: We have entered a golden age for radio astronomy, accentuated by the current suite of mm-to-m wavelength instruments. These will be greatly enhanced by the two SKA1 telescopes set to begin operating toward the end of this decade. SKA1-LOW in Western Australia will operate at frequencies between 50 and 350 MHz, while SKA1-MID in the Karoo of South Africa will operate at frequencies above 350 MHz. Together they will provide the long-wavelength radio continuum imaging of AGN and star-forming galaxies that will complement multi-wavelength surveys of the distant Universe. Furthermore, spectral line observations of 21cm HI and molecules such as Carbon Monoxide in distant galaxies will constrain their gas kinematics, as well as ISM properties such as atomic gas mass. These surveys will reveal unexpected transient phenomena to be followed-up at other wavelengths, while the SKA1 telescopes will have the capability to reveal rapid long-wavelength counterparts to multi-messenger events. I will provide a summary of the status of SKA1 construction, and highlight some of the opportunities for synergies with forthcoming facilities.

84-Title: Morphology and Kinematics of Molecular Gas in the Double-barred Galaxy NGC 3504
Author: Yu-Ting Wu  1, @  , Alfonso Trejo, Daniel Espada, Yusuke Miyamoto, @
Affiliation: 1: NAOJ, Japan
Abstract: We present the results of ALMA CO(2-1) observation of the double-barred galaxy NGC 3504. With twenty times higher resolution (~0.8") than previous works, the inner molecular gas bar and inner spiral arm-like structures reveal in the central 1 kpc (~10") region. Furthermore, in the outer bar region, the CO emission is clearly aligned with the dust lanes. To investigate the kinematics in NGC 3504, we used Kinemetry (Krajnovic et al. 2006) to fit our velocity (moment 1) map and quantify the contribution of circular rotation as well as perturbations. We found that the circular rotation is dominated in all-region and the radial motions exist in the innermost ∼0.3 kpc and at R>1 kpc. Based on this study, we are looking for an opportunity to observe double-barred galaxies at high redshifts using new-generation radio telescopes, such as SKA.

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85-Title: Star formation and AGN activity in closely interacting galaxies using MUSE, UVIT, and IRSF
Author: Jyoti Yadav  1, @  , Mousumi Das  1, @  , Sudhanshu Barway  1, @  
Affiliation: 1: Indian Institute of Astrophysics
Abstract: Interactions and mergers of gas-rich galaxies can trigger star formation in their nuclear and disk regions, leading to starbursts and active galactic nuclear (AGN) activity. Galaxy mergers also lead to the formation of supermassive black hole binaries that may start accreting gas and become single or dual AGN. The enhanced star formation will ultimately lead to bulge growth accompanied by starburst/AGN feedback activity. Apart from these effects, tidal dwarf galaxies may also form in the extended arms. These processes are all important for galaxy evolution and need to be understood in detail. Our study aims to understand these diverse processes using UV and optical observations of a sample of southern interacting galaxies. We have obtained deep, near-IR observations using the SAAO. We use UVIT observations and MUSE archival data to find signatures of AGN activity and study its connection with the surrounding star formation. The UVIT images also show star formation in the tidal tails and are important for understanding tidal dwarf galaxy formation. The star formation is also are visible in Halpha images obtained from MUSE. We present some preliminary results on the galaxy IC5110, whose BPT plot shows that it has a LINER like an object. Still, the MUSE data reveals that the emission is from a retired galaxy that has similar line ratios as those of a LINER We also found signatures of outflow from the central region in one of the galaxy.


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