Interstellar dust is still a dominant uncertainty in Astronomy, limiting precision in e.g., cosmological distance estimates and models of how light is re-processed within a galaxy. When a foreground galaxy serendipitously overlaps a more distant one, the latter backlights the dusty structures in the nearer foreground galaxy. Such an overlapping or occulting galaxy pair can be used to measure the distribution of dust in the closest galaxy with great accuracy. The STARSMOG program uses Hubble to map the distribution of dust in foreground galaxies in fine (<100 pc) detail. Integral Field Unit (IFU) observations will map the effective extinction curve, disentangling the role of fine-scale geometry and grain composition on the path of light through a galaxy. The overlapping galaxy technique promises to deliver a clear understanding of the dust in galaxies: geometry, a probability function of dimming as a function of galaxy mass and radius, and its dependence on wavelength.

Zoom recording: https://uky.zoom.us/rec/share/ApA_YxbNmZhyvRh6jOJV2-1oZh-8L1zw9O_kKivxWqPvTl1eiVTbv07if7cFx0bO.v9GsO7V4klwdB90p

The 7 Ms Chandra X-ray Observatory exposure on the Chandra

Deep Field-South (CDF-S) has provided the most sensitive

extragalactic X-ray survey by a wide margin. About 1050

X-ray sources have been detected, primarily distant active

galactic nuclei (AGNs) and starburst/normal galaxies. The

unmatched deep multiwavelength coverage for these sources

allows superb follow-up investigations, revealing the

details of supermassive black hole growth over most of

cosmic time. I will briefly describe the sources in the

7 Ms CDF-S and highlight some exciting science results.

The latter will include (1) evidence for black-hole vs.

bulge co-evolution in the distant universe; (2) constraints

on supermassive black hole growth in the first galaxies as

revealed by direct detection and stacking; and (3) the

discovery of representatives of a new population of faint,

fast X-ray transient sources. Finally, I will discuss some

future prospects for X-ray surveys of AGNs in the distant

universe, including the ongoing 5 Ms XMM-SERVS survey of

the LSST Deep Drilling Fields and new X-ray missions.

Over the past decades, the discovery of a large number of young massive clusters (YMCs) in the local Universe and giant clumps in high-z galaxies suggests that clustered star formation is the dominant star formation mode across cosmic time. Mass and energy feedback from these enormous clusters is inevitably responsible for shaping their host galaxies. In this talk, I will discuss the tight relationship between giant molecular clouds on small scales and galaxies on large scales and provide the first attempts to bring star formation and galaxy formation community together. On the one hand, the properties of YMCs and GMCs populations can be used to calibrate and help improve the current cosmological simulations. On the other hand, galaxy formation simulations provide the perfect initial conditions for the modeling GMCs in realistic environments. Finally, bringing together the collective wisdom from both galaxy and star formation, I will highlight some of my recent works on solving the mystery of the origin of globular cluster populations in the Universe.

Zoom Recording: https://uky.zoom.us/rec/share/gU3PD8lWcY7ckp8yX1hzar4ehA2fRStP3in6YZPpUFYvsIVbmRrsxNpoHvP3qCOw.8tPxhtnTxMA4vByE

Magnetic fields in the intracluster medium (ICM) affect the structure and the evolution of galaxy

clusters. However, their properties are largely unknown, and measuring magnetic fields in galaxy

clusters is challenging, especially on large-scales outside of individual radio sources. Here we

probe the plane-of-the-sky orientation of magnetic fields in clusters using the intensity gradients.

The technique is a branch of the Gradient Technique (GT) that employs emission intensity maps

from turbulent gas. We utilize the Chandra X-ray images of the Perseus, M 87, Coma, and

A2597 galaxy clusters, and the VLA radio observations of the synchrotron emission from

Perseus. We find that the fields predominantly follow the sloshing arms in Perseus, which is in

agreement with numerical simulations. The GT-predicted magnetic field shows signatures of

magnetic draping around rising bubbles driven by supermassive black hole (SMBH) feedback in

the centers of cool-core clusters, as well as draping around substructures merging with the Coma

cluster.

Zoom Recording: https://uky.zoom.us/rec/share/mkGB72TcxVuohGMJ5EVwN282koaKcMinbki7FuSKX3UvAwcl4j22df-zG5VZJnS_.gnvslk37Wx91DbZZ

The Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) is a narrow band, very wide field cosmological and astrophysical survey to be carried out from the Javalambre Astrophysical Observatory in Spain with a purpose-built, dedicated 2.5m telescope and a 5 sq.deg. 1.2Gpix camera. With first light obtained in June 2020, J-PAS plans to observe >8000sq.deg. of Northern Sky and measure sigma_z~0.003(1+z) photo-z for up to 9E7 LRG and ELG galaxies plus several million QSOs, sampling an effective volume of ~ 14 Gpc^3 up to z~1.3 reaching Stage IV radial BAO experiment. J-PAS is expected to detect ~7E5 galaxy clusters and groups, setting constraints on Dark Energy which rival those obtained from its BAO measurements. 

Thanks to the superb characteristics of the site (seeing ~0.7 arcsec), J-PAS is expected to obtain a deep, sub-arcsec multi-band image of the Northern sky, which combined with its unique photo-z precision will have an immense legacy value for almost all astrophysical areas. The key to the J-PAS potential is its innovative approach: a contiguous system of 54+2 filters with 145A width, placed 100A apart over a multi-degree FoV is a powerful "redshift machine", with the survey speed of a 4000 multiplexing low resolution spectrograph. Its commissioning camera, the PathFinder, has collected data since 2018 with all J-PAS filters of a variety of targets and fields, in particular of the AEGIS field (miniJPAS) as a proof of concept for photo-z depth and others. 

Here I will present the status of J-PAS, the main results of miniJPAS and how it impacts the expectations for J-PAS.

Zoom recording: https://uky.zoom.us/rec/share/F9E1ic1VTD7A1b0uY0c6sWNlWtCvII8N1eESjj8WC4UNIHGTzMJzxRa_mj3iIdnL.ay0DT-aSZ6MRRBTU

Giant molecular clouds (GMCs) are the primary reservoir of cold molecular gas in the interstellar medium and sites of ongoing star formation. It has been known for decades that star formation efficiency (SFE) of GMCs is very low. While UV radiation feedback from massive stars are expected to play a crucial role in controlling the GMC lifetime and SFE, our theoretical understanding of how it actually works in turbulent, magnetized clouds remains incomplete. In this talk, I will report recent progress we made in modeling GMC destruction by UV radiation feedback. I will first briefly review the predictions made by 1D models about SFE, cloud lifetime, and importance of photoionization and radiation pressure in different star-forming environments. I will then present the results of radiation (magneto)hydrodynamic simulations of star-forming GMCs and discuss how turbulence and magnetic fields can change the picture. If time allows, I will also talk about ongoing efforts in modeling GMC evolution with all major forms of feedback processes (radiation/winds/SNe).

In recent work, we have obtained improved measurements of the properties of the Milky Way and used the results to select a sample of Milky Way analog (MWA) galaxies from the Sloan Digital Sky Survey (SDSS) whose distributions of stellar mass and star formation rate match our Galaxy’s, incorporating all uncertainties. Relying on the Copernican assumption that the Milky Way should not be extraordinary, the colors and luminosities of the MWAs constrain the possible properties of our own Galaxy. This has enabled us to explore how our Galaxy fits in with the broader population; for instance, we can determine whether its properties are consistent with the power-law scaling relations exhibited by other spiral galaxies. The results have significant implications for the development of computational models of galaxy evolution in a cosmological context.  I will also describe follow-up work exploring the population of satellite galaxies in Milky Way-like dark matter halos.  It has been a long-standing puzzle why the Milky Way has considerably fewer satellite galaxies discovered to date than the typical number of satellite dark matter halos that would be found in a dark matter halo as massive as that which contains our Galaxy.  I will show that almost half of this ‘missing satellites’ problem can be explained by well-established ways in which our Galaxy’s dark matter halo is atypical.  Finally, if time allows I will also describe new work on the density profile of dark matter halos when mass within subhalos, which can often host individual galaxies, is not counted as part of the parent halo.  Widely-used profiles (such as Navarro Frenk and White) perform poorly at representing the smooth centrally-concentrated component of the halo, but there are simple functional forms which do better.

Zoom recording: https://uky.zoom.us/rec/play/58uXDQDw95A6o5P7owEDEwzb-X3PhCXv8WevwQSdhV…

The HI-MaNGA survey is an HI (21cm line) follow-up program for the SDSS-IV MaNGA survey.  I will describe the HI-MaNGA survey, its progress to date, and future plans.  I will then present new results where we combine HI-MaNGA and MaNGA data to investigate how the global HI content of star-forming galaxies relates to the mean properties of their ISM derived from optical emission lines, including integrated equivalent width, metallicity, ionization parameter, and the relative strength of low-ionization lines such as [SII] and [OI]. This analysis allows us to understand if and how the properties of the ISM vary between the most gas-rich galaxies to the most gas-poor, and how such variations may affect their evolution.  I will also discuss how gas content relates to the nuclear ionizing source (e.g., Seyfert, LINER, HII regions) and whether we find any evidence that AGN contribute to gas deficiency in the galaxy population.

Zoom Recording: https://uky.zoom.us/rec/share/xGrDewYs7rui5ao4A-_hr_N5r8_c6mkGkiksm--I61WP-hQ8VhJn9HM8fTadgDUG.M9oUhbMc-oa1r2Nr