J/A+A/670/A21 The HI content of Hickson Compact Groups (Jones+, 2023)
Disturbed, diffuse, or just missing?
A global study of the HI content of Hickson compact groups.
Jones M.G., Verdes-Montenegro L., Moldon J., Damas-Segovia A., Borthakur S.,
Luna S., Yun M.S., del Olmo A., Perea J., Cannon J., Lopez Gutierrez D.,
Cluver M., Garrido J., Sanchez S.
<Astron. Astrophys. 670, A21 (2023)>
=2023A&A...670A..21J 2023A&A...670A..21J (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, spectra ; H I data ; Radio lines ; Galaxies, nearby
Keywords: galaxies: evolution - galaxies: groups - galaxies: interactions -
galaxies: ISM - radio lines: ISM
Abstract:
Hickson compact groups (HCGs) are dense configurations of four to ten
galaxies, whose HI morphology appears to follow an evolutionary
sequence of three phases, with gas initially confined to galaxies,
then significant amounts spread throughout the intra-group medium, and
finally with almost no gas remaining in the galaxies themselves. It
has also been suggested that several groups may harbour a diffuse HI
component that is resolved out by interferometric observations.
The HI deficiency of HCGs is expected to increase as the HI
morphological phase progresses along the evolutionary sequence. If
this is the case, HI deficiency would be a rough proxy for the age and
evolutionary state of a HCG. We aim to test this hypothesis for the
first time using a large sample of HCGs and to investigate the
evidence for diffuse HI in HCGs.
We performed a uniform reduction of all publicly available VLA HI
observations (38 HCGs) with a purpose-built pipeline that also
maximises the reproducibility of this study. The resulting HI data
cubes were then analysed with the latest software tools to perform a
manual separation of emission features into those belonging to
galaxies and those extending into the intra-group medium. We thereby
classified the HI morphological phase of each group as well as
quantified their HI deficiency compared to galaxies in isolation.
We find little evidence that HI deficiency can be used as a proxy for
the evolutionary phase of a compact group in either of the first two
phases, with the distribution of HI deficiency being consistent in
both. However, for the final phase, the distribution clearly shifts to
high HI deficiencies, with more than 90% of the expected HI content
typically missing. Across all HCGs studied, we identify a few cases
where there is strong evidence for a diffuse gas component in the
intra-group medium, which might be detectable with improved
observations. We also classify a new sub-phase where groups contain a
lone HI-bearing galaxy, but are otherwise devoid of gas.
The new morphological phase we have identified is likely the result of
an evolved, gas-poor group acquiring a new, gas-rich member. The large
spread of HI deficiencies in the first two morphological phases
suggests that there is a broad range of initial HI content in HCGs,
which is perhaps influenced by large-scale environment, and that the
timescale for morphological changes is, in general, considerably
shorter than the timescale for the destruction or consumption of
neutral gas in these systems.
Description:
Here we present the tables of HI measurements from the paper.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 66 38 HCG HI sample
table2.dat 61 38 HI deficiency of HCGs
tablec1.dat 89 168 The HI content of Hickson Compact Groups
list.dat 149 76 List of fits datacubes
fits/* . 76 Individual fits datacubes
--------------------------------------------------------------------------------
See also:
VII/213 : Hickson's compact groups of Galaxies (Hickson+ 1982-1994)
J/ApJ/821/113 : HCG and RSCG compact group galaxies with WISE (Zucker+ 2016)
J/A+A/609/A17 : AMIGA XIII. HI properties (Jones+ 2018)
J/A+A/632/A78 : A case study of the HI content of HCG 16 (Jones+ 2019)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- HCG [1/100] HCG number (Cat. VII/213)
5 I1 --- Nmemb [2/8] Number of galaxies in group
7- 15 F9.5 deg RAdeg Group right ascension (J2000)
17- 25 F9.5 deg DEdeg Group declination (J2000)
27- 31 I5 km/s HRV Group heliocentric radial velocity
33- 35 I3 Mpc Dist [0/160] Group distance (1)
37- 41 A5 --- VLAConfig VLA configuration(s) the group was
observed with
43- 46 F4.1 km/s DVChan Channel width of reduced VLA HI observations
48- 51 F4.2 mJy/beam rms RMS noise in reduced VLA HI cube
53- 56 F4.1 arcsec beamMaj Major axis diameter of VLA synthesized beam
58- 61 F4.1 arcsec beamMin Minor axis diameter VLA synthesized beam
63- 66 F4.1 10+19cm-2 NHI 4-sigma HI column density sensitivity
(over 20km/s)
--------------------------------------------------------------------------------
Note (1): group distance calculated via the Cosmicflows-3 model
(Tully et al., 2016AJ....152...50T 2016AJ....152...50T, Cat. J/AJ/152/50;
Kourkchi et al.. 2020AJ....159...67K 2020AJ....159...67K), which have uncertainties of 3Mpc,
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- HCG [2/100] HCG number (Cat. VII/213)
5 A1 --- l_logMHI-VLA [<] Upper limit flag for HI mass from VLA
7- 11 F5.2 [Msun] logMHI-VLA Logarithm of total group HI mass from VLA
13- 16 F4.2 [Msun] e_logMHI-VLA ?=- Uncertainty in HI mass from VLA
18- 22 F5.2 [Msun] logMHI-GBT ?=- Logarithm of total group HI mass from
GBT observations (Borthakur et al.,
2010ApJ...710..385B 2010ApJ...710..385B)
24- 28 F5.2 [Msun] logMHI-pred Logarithm of predicted total group HI mass
based on B-band luminosity
(Jones et al., 2016MNRAS.457.4393J 2016MNRAS.457.4393J)
30 A1 --- l_HIdef-VLA [>] Lower limit flag for HI deficiency
from the VLA
32- 36 F5.2 --- HIdef-VLA HI deficiency of group from VLA HI mass
38- 42 F5.2 --- HIdef-GBT ?=- HI deficiency of group from GBT
HI mass
44- 48 F5.2 [Msun] logMHI-gals ?=- Total HI mass in galaxies (VLA)
50- 53 F4.2 [Msun] logMHI-exfs ?=- Total HI mass in extended features
(VLA)
55- 58 F4.2 --- fexfs ?=- Fraction of HI mass in extended
features (VLA)
60- 61 A2 --- HIphase HI morphological phase (cf.
Verdes-Montenegro et al.,
2001A&A...377..812V 2001A&A...377..812V)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablec1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- HCG [2/100] HCG number (Cat. VII/213)
5- 14 A10 --- Name Galaxy name
16- 24 F9.5 deg RAdeg Galaxy right ascension (J2000)
26- 34 F9.5 deg DEdeg Galaxy declination (J2000)
36- 39 A4 --- MType Galaxy morphological type (Hickson et al.,
1989ApJS...70..687H 1989ApJS...70..687H, Cat. VII/213)
41- 49 A9 --- IRclass IR activity classification (Zucker et al.,
2016ApJ...821..113Z 2016ApJ...821..113Z, Cat. J/ApJ/821/113)
51- 55 I5 km/s HRV Galaxy heliocentric radial velocity
(Hickson et al., 1992ApJ...399..353H 1992ApJ...399..353H,
Cat. VII/213)
57- 61 F5.2 mag Bmag Galaxy B-band apparent magnitude
(Hickson et al., 1989ApJS...70..687H 1989ApJS...70..687H,
Cat. VII/213)
63- 66 F4.2 mag e_Bmag Uncertainty in B-band apparent magnitude
68- 72 F5.2 [Msun] logMHI-pred Logarithm of predicted HI mass
(Jones et al., 2018A&A...609A..17J 2018A&A...609A..17J,
Cat. J/A+A/609/A17)
74- 77 F4.2 [Msun] e_logMHI-pred Uncertainty in predicted HI mass
79- 83 F5.2 [Msun] logMHI ?=- Logarithm of HI mass (VLA)
85- 89 F5.2 --- HIdef ?=- Galaxy HI deficiency (VLA)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- HCG [2/100] HCG number (Cat. VII/213)
5- 13 F9.5 deg RAdeg Right Ascension of center (J2000)
14- 22 F9.5 deg DEdeg Declination of center (J2000)
24- 27 I4 --- Nx Number of pixels along X-axis
29- 32 I4 --- Ny Number of pixels along Y-axis
34- 36 I3 --- Nz Number of pixels along Z-axis
38- 63 A26 "datime" Obs.date Observation date
65- 75 E11.6 m/s bVRAD Lower value of VRAD interval
77- 87 E11.6 m/s BVRAD Upper value of VRAD interval
89- 96 F8.2 m/s dVRAD VRAD resolution
98-103 I6 Kibyte size Size of FITS file
105-124 A20 --- FileName Name of FITS file, in subdirectory fits
126-149 A24 --- Title Title of the FITS file
--------------------------------------------------------------------------------
Acknowledgements:
Michael Jones, jonesmg(at)arizona.edu
(End) Patricia Vannier [CDS] 05-Dec-2022