New lessons from the H i size–mass relation of galaxies

Wang, Jing; Koribalski, B. S.; Serra, P.; Hulst, J. M. van der; Roychowdhury, Sambit; Kamphuis, P.; Chengalur, Jayaram N.

doi:10.1093/mnras/stw1099

Cited by 250 publications

(390 citation statements)

References 64 publications

Supporting

Mentioning

337

Contrasting

Order By: Relevance

“…For each radio source, we determine a matched galaxy if: (a) it has a spectroscopic redshift within the range for H I covered by the ASKAP-12 spectrum, and (b) within an impact parameter of 50 kpc, which is the maximum galactocentric radius typically seen for H I discs (e.g. Wang et al 2016, see also Bland-Hawthorn et al 2017) and within which 21-cm absorption is expected to be detected (e.g. Reeves et al 2016;Curran et al 2016a;Borthakur 2016;Dutta et al 2017).…”

Section: Cross-matching With Optically Identified Galaxiesmentioning

confidence: 99%

“…If the absorber detected in GAMA J224500.05-343031.7 does form part of a larger H I disc, then the H I sizemass relation (see e.g. Wang et al 2016 and references therein) would imply a total H I mass of M HI 3 × 10 9 M . Massive and extended H I discs are rare in early type galaxies, but have been seen in the nearby Universe (Serra et al 2012c).…”

Section: Cross-matching With Optically Identified Galaxiesmentioning

confidence: 99%

See 1 more Smart Citation

FLASH early science – discovery of an intervening H i 21-cm absorber from an ASKAP survey of the GAMA 23 field

Allison

Sadler

Bellstedt

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We present early science results from the First Large Absorption Survey in H I (FLASH), a spectroscopically blind survey for 21-cm absorption lines in cold hydrogen (H I) gas at cosmological distances using the Australian Square Kilometre Array Pathfinder (ASKAP). We have searched for H I absorption towards 1253 radio sources in the GAMA 23 field, covering redshifts between z = 0.34 and 0.79 over a sky area of approximately 50 deg 2 . In a purely blind search we did not obtain any detections of 21-cm absorbers above our reliability threshold. Assuming a fiducial value for the H I spin temperature of T spin = 100 K and source covering fraction c f = 1, the total comoving absorption path length sensitive to all Damped Lyman α Absorbers (DLAs; N HI ≥ 2 × 10 20 cm −2 ) is ∆X = 6.6 ± 0.3 (∆z = 3.7 ± 0.2) and super-DLAs (N HI ≥ 2 × 10 21 cm −2 ) is ∆X = 111 ± 6 (∆z = 63 ± 3). We estimate upper limits on the H I column density frequency distribution function that are consistent with measurements from prior surveys for redshifted optical DLAs, and nearby 21-cm emission and absorption. By cross-matching our sample of radio sources with optical spectroscopic identifications of galaxies in the GAMA 23 field, we were able to detect 21-cm absorption at z = 0.3562 towards NVSS J224500−343030, with a column density of N HI = (1.2±0.1)×10 20 (T spin /100 K) cm −2 . The absorber is associated with GAMA J22450.05−343031.7, a massive early-type galaxy at an impact parameter of 17 kpc with respect to the radio source and which may contain a massive (M HI 3 × 10 9 M ) gas disc. Such gas-rich early types are rare, but have been detected in the nearby Universe.

show abstract

Section: Cross-matching With Optically Identified Galaxiesmentioning

confidence: 99%

Section: Cross-matching With Optically Identified Galaxiesmentioning

confidence: 99%

FLASH early science – discovery of an intervening H i 21-cm absorber from an ASKAP survey of the GAMA 23 field

Allison

Sadler

Bellstedt

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…In this way we can estimate the depletion time considering only the gas which is predicted to be contained within the optical disk. We use the Hi size-mass relation from Wang et al (2016) to predict an Hi size using only the Hi mass of each galaxy in our sample. We also adopt a simple exponential profile for the radial Hi mass distribution.…”

Section: Predicting Gas Location From Scaling Relations and Predictinmentioning

confidence: 99%

xGASS: cold gas content and quenching in galaxies below the star-forming main sequence

Janowiecki

Catinella

Cortese

et al. 2020

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

We use Hi and H 2 global gas measurements of galaxies from xGASS and xCOLD GASS to investigate quenching paths of galaxies below the star formation main sequence (SFMS). We show that the population of galaxies below the SFMS is not a 1:1 match with the population of galaxies below the Hi and H 2 gas fraction scaling relations. Some galaxies in the transition zone (TZ) 1-sigma below the SFMS can be as Hi-rich as those in the SFMS, and have on average longer gas depletion timescales. We find evidence for environmental quenching of satellites, but central galaxies in the TZ defy simple quenching pathways. Some of these so-called "quenched" galaxies may still have significant gas reservoirs and be unlikely to deplete them any time soon. As such, a correct model of galaxy quenching cannot be inferred with SFR (or other optical observables) alone, but must include observations of the cold gas. We also find that internal structure (particularly, the spatial distribution of old and young stellar populations) plays a significant role in regulating the star formation of gas-rich isolated TZ galaxies, suggesting the importance of bulges in their evolution.

show abstract

“…Bosma Fig. 17 Statistics of the ratio of HI diameter, evaluated at Σ HI = 1 M pc −2 , to the optical diameter, following Wang et al (2016), except for the Bluedisk sample, for which Wang et al (2013) Ponomareva et al 2016. Note that several large galaxies are missing from the LVHIS, THINGS, LITTLE THINGS, FIGGS and VIVA samples, while for the WHISP samples a maximum diameter of 400 is imposed, on account of missing flux when comparing the interferometric data with single-dish observations or too large in extent compared to the primary beam.…”

Section: The Relation Between Hi Extent and The Optical Radiusmentioning

confidence: 99%

Hi in the Outskirts of Nearby Galaxies

Bosma

2017

Astrophysics and Space Science Library

View full text Add to dashboard Cite

The HI in disk galaxies frequently extends beyond the optical image, and can trace the dark matter there. I briefly highlight the history of high spatial resolution HI imaging, the contribution it made to the dark matter problem, and the current tension between several dynamical methods to break the disk-halo degeneracy. I then turn to the flaring problem, which could in principle probe the shape of the dark halo. Instead, however, a lot of attention is now devoted to understanding the role of gas accretion via galactic fountains. The current Λ cold dark matter theory has problems on galactic scales, such as the core-cusp problem, which can be addressed with HI observations of dwarf galaxies. For a similar range in rotation velocities, galaxies of type Sd have thin disks, while those of type Im are much thicker. After a few comments on modified Newtonian dynamics and on irregular galaxies, I close with statistics on the HI extent of galaxies.

show abstract

New lessons from the H i size–mass relation of galaxies

Cited by 250 publications

References 64 publications

FLASH early science – discovery of an intervening H i 21-cm absorber from an ASKAP survey of the GAMA 23 field

FLASH early science – discovery of an intervening H i 21-cm absorber from an ASKAP survey of the GAMA 23 field

xGASS: cold gas content and quenching in galaxies below the star-forming main sequence

Hi in the Outskirts of Nearby Galaxies

Contact Info

Product

Resources

About