| 1. |
- Karki, Arjun, et al.
(författare)
-
MUSE-ALMA Haloes - IX. Morphologies and stellar properties of gas-rich galaxies
- 2023
-
Ingår i: Monthly notices of the Royal Astronomical Society. - 0035-8711 .- 1365-2966. ; 524:4, s. 5524-5547
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding how galaxies interact with the circumgalactic medium (CGM) requires determining how galaxies’ morphological and stellar properties correlate with their CGM properties. We report an analysis of 66 well-imaged galaxies detected in Hubble Space Telescope and Very Large Telescope MUSE observations and determined to be within ±500 km s−1 of the redshifts of strong intervening quasar absorbers at 0.2 ≲ z ≲ 1.4 with H I column densities NHI>1018cm−2�HI>1018cm−2. We present the geometrical properties (Sérsic indices, effective radii, axis ratios, and position angles) of these galaxies determined using GALFIT. Using these properties along with star formation rates (SFRs, estimated using the H α or [O II] luminosity) and stellar masses (M* estimated from spectral energy distribution fits), we examine correlations among various stellar and CGM properties. Our main findings are as follows: (1) SFR correlates well with M*, and most absorption-selected galaxies are consistent with the star formation main sequence of the global population. (2) More massive absorber counterparts are more centrally concentrated and are larger in size. (3) Galaxy sizes and normalized impact parameters correlate negatively with NHI, consistent with higher NHI absorption arising in smaller galaxies, and closer to galaxy centres. (4) Absorption and emission metallicities correlate with M* and specific SFR, implying metal-poor absorbers arise in galaxies with low past star formation and faster current gas consumption rates. (5) SFR surface densities of absorption-selected galaxies are higher than predicted by the Kennicutt–Schmidt relation for local galaxies, suggesting a higher star formation efficiency in the absorption-selected galaxies.
|
|
| 2. |
- Nave, Gillian, et al.
(författare)
-
Atomic data for astrophysics : Needs and challenges
- 2019
-
Ingår i: Bulletin of the American Astronomical Society.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We describe the impact of atomic spectroscopy on astrophysics and future requirements for atomic data. These requirements cannot be met with current levels of funding for laboratory astrophysics. The situation could be substantially improved with relatively small investment from the funding agencies.
|
|
| 3. |
- Weng, Simon, et al.
(författare)
-
MUSE-ALMA Haloes XI : gas flows in the circumgalactic medium
- 2023
-
Ingår i: Monthly notices of the Royal Astronomical Society. - 0035-8711 .- 1365-2966. ; 523:1, s. 676-700
-
Tidskriftsartikel (refereegranskat)abstract
- The flow of gas into and out of galaxies leaves traces in the circumgalactic medium which can then be studied using absorption lines towards background quasars. We analyse 27 log[N(H I) /cm(-2)] > 18. 0 H I absorbers at z = 0.2 to 1.4 from the MUSEALMA Haloes survey with at least one galaxy counterpart within a line of sight velocity of +/- 500 km s(-1). We perform 3D kinematic forward modelling of these associated galaxies to examine the flow of dense, neutral gas in the circumgalactic medium. From the VLT/MUSE, HST broad-band imaging, and VLT/UVES and Keck/HIRES high-resolution UV quasar spectroscopy observations, we compare the impact parameters, star-formation rates, and stellar masses of the associated galaxies with the absorber properties. We find marginal evidence for a bimodal distribution in azimuthal angles for strong H I absorbers, similar to previous studies of the Mg II and O VI absorption lines. There is no clear metallicity dependence on azimuthal angle, and we suggest a larger sample of absorbers is required to fully test the relationship predicted by cosmological hydrodynamical simulations. A case-by-case study of the absorbers reveals that ten per cent of absorbers are consistent with gas accretion, up to 30 per cent trace outflows, and the remainder trace gas in the galaxy disc, the intragroup medium, and low-mass galaxies below the MUSE detection limit. Our results highlight that the baryon cycle directly affects the dense neutral gas required for star-formation and plays a critical role in galaxy evolution.
|
|
