Conveners
Parallel Session: Extreme Astrophysics / Galaxies & Cosmology
- Nikki Zabel (University of Groningen)
The current state-of-the-art cosmological simulations do not treat dust physics. Given the significant impact of dust on the observables, this is done at a post-processing stage. A number of post-processing studies using the SKIRT radiative transfer code have shown that the UV broadband fluxes and IR colors are a source of tension with observational data. Various reasons have been attributed...
We present a robust representation of the galaxy group NGC 5813's chemical and thermal structure analysing archival, deep X-ray observations of the group using up to date atomic line emission models and multi temperature spectral model. The selection of our target is motivated by the fact that NGC 5813 has a very relaxed morphology, making it a promissing candidate for the study of the AGN...
Following a close dynamical encounter with Sgr A, stellar binaries in the Galactic Centre (GC) can be tidally separated. One member star remains bound to Sgr A and the other is ejected as a hyper-velocity star (HVS) with a velocity beyond the escape speed of the Milky Way. The abundance and properties of these objects can provide insight into still-uncertain aspects of the stellar...
The state of the neutral interstellar medium critically affects the galactic star formation process and baryon cycle. Cosmological simulations which emulate galaxy evolution for a statistical sample of galaxies typically do not consider the transition of atomic to molecular hydrogen in the cold neutral medium. To compare the simulation output to observations, the atomic and molecular fractions...
We present central stellar velocity dispersion measurements for 158 type 1 AGNs from the second data release of the Swift/BAT AGN Spectroscopic Survey (BASS DR2) with a redshift cut-off z < 0.08. A total number of 297 type 1 AGN spectra are fit for obtaining two independent measurements from the Ca II H+K + Mg I region (3880 - 5550 ̊A) and the calcium triplet region (8350-8750 ̊A). The...
Relatively massive galaxies such as the Milky Way are expected from theoretical galaxy formation and cosmological simulations to contain a hot gas corona extending to roughly the virial radius. In the Milky Way the existence of this hot corona has been established mainly relatively close to the galactic disc through observations in absorption and X-ray emission. Most constraints on the density...
The recent MeerKAT deep surveys in the nearby Universe opened a new era of investigation of the neutral atomic (HI) gas in nearby galaxies. By reaching high spatial and spectral resolution with short observations, along with a large field of view (~1 degree), MeerKAT now enables us to investigate the presence of low-column density (~1x10^18 cm^-2) HI in all types of galaxies in different...
Large amounts of gas and dust are found in the central regions of most active galaxies. These ambient media play a crucial role as they provide the accretion reservoir powering AGNs and reprocess the X-ray, UV and optical emission of the central engine. Yet, the detailed characteristics of these regions and the physics behind them remain unknown. Recent radiative transfer modelling suggests...
Protoclusters are progenitors of galaxy clusters at the present day and are important for studying how halo mass and stellar mass assemble in the early universe. Tracing signposts that are expected to live in dense regions is a widely adopted method to identify protoclusters. Bright dusty star-forming galaxies (DSFG) are one of these signposts. Hyperluminous infrared galaxies (HLIRGs), which...
