J/ApJ/915/70 WALLABY pilot survey: HI gas in Hydra cluster (Wang+, 2021)
WALLABY pilot survey: the diversity of ram pressure stripping of the Galactic
HI gas in the Hydra cluster.
Wang J., Staveley-Smith L., Westmeier T., Catinella B., Shao L.,
Reynolds T.N., For B.-Q., Lee B., Liang Z.-Z., Wang S., Elagali A.,
Denes H., Kleiner D., Koribalski B.S., Lee-Waddell K., Oh S.-H.,
Rhee J., Serra P., Spekkens K., Wong O.I., Bekki K., Bigiel F.,
Courtois H.M., Hess K.M., Holwerda B.W., McQuinn K.B.W., Pandey-Pommier M.,
van der Hulst J.M., Verdes-Montenegro L.
<Astrophys. J., 915, 70 (2021)>
=2021ApJ...915...70W 2021ApJ...915...70W
ADC_Keywords: Galaxies; H I data; Surveys; Intergalactic medium
Keywords: Disk galaxies ; Galaxies ; Interstellar atomic gas ;
Galaxy evolution ; Galaxy environments
Abstract:
This study uses HI image data from the Widefield ASKAP L-band Legacy
All-sky Blind surveY (WALLABY) pilot survey with the Australian Square
Kilometre Array Pathfinder (ASKAP) telescope, covering the Hydra
cluster out to 2.5r200. We present the projected phase-space
distribution of HI-detected galaxies in Hydra, and identify that
nearly two-thirds of the galaxies within 1.25r200 may be in the
early stages of ram pressure stripping. More than half of these may be
only weakly stripped, with the ratio of strippable HI (i.e., where the
galactic restoring force is lower than the ram pressure in the disk)
mass fraction (over total HI mass) distributed uniformly below 90%.
Consequently, the HI mass is expected to decrease by only a few 0.1dex
after the currently strippable portion of HI in these systems has been
stripped. A more detailed look at the subset of galaxies that are
spatially resolved by WALLABY observations shows that, while it
typically takes less than 200Myr for ram pressure stripping to remove
the currently strippable portion of HI, it may take more than 600Myr
to significantly change the total HI mass. Our results provide new
clues to understanding the different rates of HI depletion and star
formation quenching in cluster galaxies.
Description:
Taking advantage of the high survey efficiency of the Australian
Square Kilometre Array Pathfinder (ASKAP), the pilot survey of
Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY;
Koribalski+ 2020Ap&SS.365..118K 2020Ap&SS.365..118K) has been targeting nearby clusters
and groups. In this study, we use its second internal data release of
the Hydra cluster.
WALLABY mapped a 60deg2 area around the Hydra cluster center,
reaching out to 4r200 and fully covering the region within 2r200.
The WALLABY observation reached a targeted sensitivity of
σcube=2.0±0.5mJy/beam, with a circular beam FWHM of
bmaj∼30" (∼7kpc at the distance of Hydra) and a velocity spectral
resolution of 4km/s.
We use the optical g- and r-band images from the second data release
of Pan-STARRS (Waters+ 2020ApJS..251....4W 2020ApJS..251....4W) to derive optical properties.
The Hydra cluster has a distance of 47.5±3Mpc and based on X-ray
data, has a radius r200∼1.35Mpc, and a mass within this radius,
M200∼3.02x1014M☉ (Reiprich & Bohringer 2002ApJ...567..716R 2002ApJ...567..716R).
Its velocity dispersion σC=620km/s is derived from M200
using the equation of Evrard+ (2008ApJ...672..122E 2008ApJ...672..122E).
Objects:
---------------------------------------------------------------
RA (ICRS) DE Designation(s)
---------------------------------------------------------------
10 36 36.00 -27 31 03.9 Hydra Cluster = NAME Hydra Cluster
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 53 90 Galaxy properties
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See also:
VIII/73 : HI Parkes All Sky Survey Catalogue (HIPASS) (Meyer+, 2004)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
J/A+A/436/443 : AMIGA. I. Velocities of CIG gal. (Verdes-Montenegro+ 2005)
J/A+A/449/929 : HI observations of Coma Supercluster (Gavazzi+, 2006)
J/MNRAS/383/1519 : Abell 1367 HI sources from AGES (Cortese+, 2008)
J/AJ/142/170 : ALFALFA survey: the α.40 HI sources (Haynes+, 2011)
J/A+A/570/A69 : GALEX Ultraviolet Virgo Cluster Survey. IV. (Boselli+, 2014)
J/MNRAS/460/2143 : HI size-mass relation of galaxies (Wang+, 2016)
J/ApJ/843/16 : Galaxy groups within 3500km/s (Kourkchi+, 2017)
J/MNRAS/476/875 : xGASS catalog (Catinella+, 2018)
J/ApJ/861/49 : ALFALFA extragalactic HI source catalog (Haynes+, 2018)
http://wallaby-survey.org/ : WALLABY survey home page
http://research.csiro.au/casda/ : CSIRO ASKAP Science Data Archive
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 3 I3 --- ID [83/272] Identifier
5- 18 A14 --- WALLABY WALLABY identifier (JHHMMSS+DDMMSS)
20- 23 F4.2 --- Dp/r200 [0.05/2.4] Cluster-centric projected distance,
dproj/r200
25- 29 F5.2 --- dV/sigC [-2.2/1.7] Velocity distance from cluster
center, Δνrad/σC
31- 34 F4.1 [Msun] logM [6.7/11] Log of stellar mass
36- 39 F4.1 [Msun] logMHI [8.2/10.1] log of HI mass
41 I1 --- Fr1 [0/1] Flag for identification of r1-RPS
candidates (1=true) (1)
43 I1 --- Frps [0/1] Flag for identification of ram pressure
stripping (RPS) candidates (both resolved
and unresolved) (2)
45- 48 F4.2 --- frpsP [0.22/1]? Fraction of HI mass under RPS
derived from predicted HI radial profiles
50- 53 F4.2 --- frpsR [0.1/0.96]? Fraction HI mass under RPS derived
from HI moment-0 maps for the resolved-RPS
candidates
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Note (1): Identification of r1-RPS candidates (the major sample studied
in Sections 3 and 4).
Note (2): The identification of unresolved RPS candidates is incomplete.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 14-Dec-2022