Conveners
Parallel Session: Galaxies & Cosmology
- Erwin de Blok (ASTRON/UCT/Groningen)
Parallel Session: Galaxies & Cosmology
- Reynier Peletier (Kapteyn Institute)
Parallel Session: Galaxies & Cosmology
- Ilse De Looze (UGent)
The observation of the far-IR 158 μm line of singly ionised carbon [CII] plays an important role in the study of star-forming regions of the interstellar medium (ISM) in galaxies. The connection between the [CII] fine-structure line and ionised phases of the ISM, could make [CII] emission a useful alternative star-formation rate (SFR) measure. However, due to the ambiguity of the origin of...
The kinematics of molecular gas on cloud scales are a sensitive probe of the boundary conditions for star formation. Until recently, such measurements were only available for cloud populations within the Local group (including our own MW). But now, new survey capabilities are expanding our view of gas motions to a greater diversity of galactic environments, providing unprecedented constraints...
The conditions under which the cold gas of galaxies evolves are not well known at higher redshift. The best way to understand cold gas is by studying the interstellar medium (ISM) of galaxies at different cosmic times. Far-infrared (FIR) emission lines are powerful tools for understanding the various phases of the ISM in galaxies. With this in mind, we have combined the cosmological EAGLE...
We present hydrodynamic simulations of the chemical evolution of the interstellar medium (ISM) gas influenced by the feedback from active galactic nuclei (AGN), coupled with the CHIMES code to treat the radiative cooling, AGN heating, and chemistry. We focus on the central 500 pc around the black hole (BH) where the AGN outflows and radiation couple to the ISM. In the simulation, we are...
The gas and dust present within galaxies, known as the Interstellar Medium (ISM), is not homogeneous; star formation, supernovae events, as well as AGN activities may all greatly alter the ISM. In particular, recent studies of nearby external galaxies have shown that the molecular ISM varies at kiloparsecs as well as at parsec scales, with evidence of different gas components traced by...
Understanding galaxy formation and evolution is one of the key goals of astronomical research. With roughly half of the galaxies in the local Universe residing in dense environments, it is therefore important to study the effects of environment on galaxy evolution. It has been known for several decades that galaxy clusters harbour a relatively large fraction of early-type galaxies, suggesting...
Non-spherical interstellar dust grains that are immersed in a magnetic field are expected to align with this field. The far-infrared (FIR) thermal emission of non-spherical grains is polarised along the longest axis of the grains. Combined, these two effects make polarised dust emission a powerful tool to study magnetic field configurations in environments where we expect a sufficiently strong...
Galaxy mergers have been observed to trigger nuclear activity by feeding gas to the central supermassive black hole. One such class of objects are Ultra Luminous InfraRed Galaxies (ULIRGs), which are mostly late stage major mergers of gas-rich galaxies. Recently, large scale (∼100 kpc) radio continuum emission has been detected in a handful of ULIRGs, all of which also harbour powerful AGNs....
The last phase transition of our Universe is Reionization, when the first galaxies emitted energetic photons that ionized the intergalactic medium (IGM). The escape of ionizing photons from complex galactic environments is a key process to understand Reionization. However, the opacity of the neutral high redshift IGM results in the need of indirect methods of studying ionizing photons. I will...
It is widely accepted that disc galaxies sustain their star formation by accreting gas from the external environment. In this study, we focus on one possible mechanism: hot CGM (corona) condensation triggered by the galactic fountain. Supernova feedback in star-forming galaxies continuously ejects out the plane part of the disc gas, which travels in the halo and falls back to the disc. This...
In the nearby (D=14 Mpc) AGN-starburst composite galaxy NGC 1068, it has been found that the molecular gas in the CND is outflowing, which is a manifestation of ongoing AGN feedback (García- Burillo et al. 2014). The induced interaction between the AGN ionized wind & jet with the molecular gas on the CND has produced large-scale molecular shocks on spatial scales of up to 400 pc from the AGN....
Weak gravitational lensing, the deflection of light rays caused by the inhomogeneous matter distributions, has been a powerful tool for observational cosmology. While promising in the application, it is demanding to measure the weak lensing signals to the desired accuracy in practice. With the ever-growing statistical powers of weak lensing surveys, it is critical to address any potential...
The relation between half-light radius and galaxy stellar mass has in recent years been studied extensively using large photometric surveys. This scaling relation has been found to be different for early types and late types, with different logarithmic slopes and zero points, and to evolve with time. While it provides important clues as to the assembly history of galaxies, the interpretation...
The formation of ultra-diffuse galaxies is one of the most actively discussed subjects in extra-galactic astronomy during the last years. Yet, no clear consensus has been reached regarding their evolutionary pathways, with a number of simulations producing UDG-like galaxies using very different feedback prescriptions and even with different dark matter haloes properties. In order to test such...
While the general properties of the very low surface brightness galaxies with large effective radii (recently been dubbed "Ultra Diffuse Galaxies" or "UDGs") were once thought to be a challenge for the existing models of galaxy formation, the triumph of recent models in reproducing these properties erases most of the raised concerns in our understating of galaxy formation...
I will present my group's work on exploiting ongoing Gaia data releases to constrain the hardly observable properties of our own Galactic Center exploiting rare unbound stars, that are ejected from the vicinity of SgrA* and travel on unbound orbit through the Milky Way Halo.
Galaxies are an amalgamation of several components (dark matter, stars, gas, and dust), constantly interacting with one another. This interaction is imprinted on the spectral energy distribution (SED) of a given galaxy. Panchromatic SED fitting can shed light on the astrophysical processes that regulate galaxy evolution. However, the current SED modeling approaches come with many caveats and...
Gaia eDR3 (and soon DR3) has revealed a number of kinematic groups in the solar neighbourhood. Some of these are now well know major accretion events such as Gaia-Enceladus-Sausage and Sequoia. Other smaller groups have been identified and their nature is not fully understood. Here I will present a method to extend the local spectroscopic sample by extrapolating the orbits of less-prominent...
