J/MNRAS/423/787 AGES sources in Virgo cluster (Taylor+, 2012)
The Arecibo Galaxy Environment Survey. V. The Virgo cluster (I).
Taylor R., Davies J.I., Auld R., Minchin R.F.
<Mon. Not. R. Astron. Soc., 423, 787-810 (2012)>
=2012MNRAS.423..787T 2012MNRAS.423..787T
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Radial velocities
Keywords: surveys - galaxies: clusters: individual: Virgo - galaxies: evolution
Abstract:
We present 21-cm observations of a 10x2deg2 region in the Virgo
cluster, obtained as part of the Arecibo Galaxy Environment Survey.
289 sources are detected over the full redshift range
(-2000<Vhel<+20000km/s) with 95 belonging to the cluster
(Vhel<3000km/s). We combine our observations with data from the
optically selected Virgo Cluster Catalogue (VCC) and the Sloan Digital
Sky Survey. Most of our detections can be clearly associated with a
unique optical counterpart, and 30 per cent of the cluster detections
are new objects fainter than the VCC optical completeness limit. Seven
detections may have no optical counterpart and we discuss the possible
origins of these objects. Seven detections appear associated with
early-type galaxies. We perform HI stacking on the HI-undetected
galaxies listed in the VCC in this region and show that they must have
significantly less gas than those actually detected in HI. Galaxies
undetected in HI in the cluster appear to be really devoid of gas, in
contrast to a sample of field galaxies from the Arecibo Legacy Fast
ALFA (ALFALFA).
Description:
Two areas of the Virgo cluster have been selected for study with AGES,
VC1 and VC2. This paper examines the VC1 area while Paper II
(2013MNRAS.428..459T 2013MNRAS.428..459T) will consider VC2 and compare the results of the
two areas.
Observations were taken in 2008 January-June, 2009 February-June, 2010
January-June and 2011 January, using the Arecibo L-band Feed Array
(ALFA) instrument on the Arecibo telescope in spectral line mode.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 107 95 HI properties of objects detected within the
Virgo cluster (cz<3000km/s)
table2.dat 107 194 HI properties of galaxies behind the Virgo cluster
(cz>3000km/s)
table3.dat 77 81 Optical properties of HI detections in the
Virgo cluster
table4.dat 72 155 *Optical properties of HI detections behind the
Virgo cluster
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Note on table4.dat: Objects with multiple or unclear optical counterparts are
omitted.
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See also:
J/MNRAS/383/1519 : Abell 1367 HI sources from AGES (Cortese+, 2008)
J/AJ/140/1093 : NGC7332/7339 & NGC1156 HI sources from AGES (Minchin+, 2010)
J/MNRAS/415/1883 : AGES HI sources in NGC 7448 (Davies+, 2011)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name (G1)
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 22 F4.1 s RAs Right ascension (J2000)
23 A1 --- --- [0]
25- 27 F3.1 s e_RAs rms uncertainty on RA (1)
30 A1 --- DE- Declination sign (J2000)
31- 32 I2 deg DEd Declination (J2000)
34- 35 I2 arcmin DEm Declination (J2000)
37- 38 I2 arcsec DEs Declination (J2000)
39- 40 A2 --- --- [.0 ]
42- 43 I2 arcsec e_DEs rms uncertainty on DE (1)
46- 50 I5 km/s HV Heliocentric Velocity of HI line
52- 53 I2 km/s e_HV rms uncertainty on HV (1)
56- 58 I3 km/s W50 Maximum velocity width at 50% of the peak flux
60- 61 I2 km/s e_W50 rms uncertainty on W50 (1)
64- 66 I3 km/s W20 Maximum velocity width at 20% of the peak flux
68- 69 I2 km/s e_W20 rms uncertainty on W20 (1)
72- 77 F6.3 Jy Flux Total HI flux
79- 83 F5.3 Jy e_Flux rms uncertainty on Flux (1)
86- 90 F5.1 Mpc Dist Distance of galaxy
92- 96 F5.2 [Msun] logMHI Estimated HI mass
98-103 F6.2 --- S/N Peak signal-to-noise ratio
105-107 F3.1 mJy rms median noise level (mJy/beam)
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Note (1): errors as computed by MIRIAD.
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Byte-by-byte Description of file: table3.dat table4.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name (G1)
13 I1 --- Flag [0/2] Flag for status of the optical
counterpart used (1)
15- 27 A13 --- OName Optical source name, when known
29- 30 I2 --- MT [-1/20] Morphological type, using the system
of the GOLDMine data base
32- 37 F6.2 mag gMAG Absolute magnitude in the g band
39- 44 F6.2 mag iMAG Absolute magnitude in the i band
46- 50 F5.2 mag g-i g-i colour index
52- 55 F4.2 Sun MHI/Lg HI mass-to-light ratio, g band
57- 61 F5.2 kpc Diam Optical diameter
63- 67 F5.2 [-] DHI ?=- Estimated HI deficiency (2)
69- 72 F4.2 arcmin Sep Ddifference between optical and HI centres
74- 77 F4.2 deg D.M49 ? Sky distance from M49, only in table3
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Note (1): Flag takes the following values:
0 = object has a matching optical redshift
1 = no optical redshift is available
2 = unexplained (concerns AGESVC1_100)
Note (2): the HI deficiency is computed as DHI = log(Mref/Mobs)
where Mref is the HI mass of the reference galaxy,
and Mobs the HI mass observed. Therefore a galaxy with DHI=1.0
has 10% of the gas of an equivalent field object.
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Global Notes:
Note (G1): the names are
* either "AGESVC1_NNN" (Arecibo Galaxy Environment Survey
in Virgo Cluster version 1);
the running number NNN varies between 001 and 306
* or "GLADOS_NNN" (Galaxy Line Analysis for Detection Of Sources),
an automatic extractor developed specifically for AGES;
the running number NNN varies between 001 and 016.
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History:
From electronic version of the journal
References:
Auld et al., Paper I 2006MNRAS.371.1617A 2006MNRAS.371.1617A
Cortese et al., Paper II 2008MNRAS.383.1519C 2008MNRAS.383.1519C, Cat. J/MNRAS/383/1519
Minchin et al., Paper III 2010AJ....140.1093M 2010AJ....140.1093M, Cat. J/AJ/140/1093
Davies et al., Paper IV 2011MNRAS.415.1883D 2011MNRAS.415.1883D, Cat. J/MNRAS/415/1883
Taylor et al., Paper VI 2013MNRAS.428..459T 2013MNRAS.428..459T
(End) Patricia Vannier [CDS] 02-Apr-2013