J/A+A/396/449 Hα surface photometry in Virgo (Gavazzi+, 2002)
Hα surface photometry of galaxies in the Virgo cluster.
IV. The current star formation in nearby clusters of galaxies.
Gavazzi G., Boselli A., Pedotti P., Gallazzi A., Carrasco L.
<Astron. Astrophys. 396, 449 (2002)>
=2002A&A...396..449G 2002A&A...396..449G
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Photometry, surface
Keywords: galaxies: photometry - galaxies: clusters: individual: Virgo
Abstract:
Hα+[NII] imaging observations of 369 late-type (spiral) galaxies
in the Virgo cluster and in the Coma/A1367 supercluster are analyzed,
covering 3 rich nearby clusters (A1367, Coma and Virgo) and nearly
isolated galaxies in the Great-Wall. They constitute an optically
selected sample (mp<16.0) observed with ∼60% completeness. These
observations provide us with the current (T<107yrs) star formation
properties of galaxies that we study as a function of the
clustercentric projected distances (Theta). The expected decrease of
the star formation rate (SFR), as traced by the Hα equivalent
width, with decreasing Theta is found only when galaxies brighter than
Mp∼19.5 are considered. Fainter objects show no or reverse trends. We
also include in our analysis Near Infrared data, providing information
on the old (T>109yrs) stars. Put together, the young and the old
stellar indicators give the ratio of currently formed stars over the
stars formed in the past, or "birthrate" parameter b. For the
considered galaxies we also determine the "global gas content"
combining HI with CO observations. We define the "gas deficiency''
parameter as the logarithmic difference between the gas content of
isolated galaxies of a given Hubble type and the measured gas content.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 56 369 Parameters of the analyzed galaxies.
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See also:
VII/190 : Zwicky Galaxy Catalog (Zwicky+ 1968)
J/AJ/90/1681 : The Virgo Cluster Catalog (VCC) (Binggeli+, 1985)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1 A1 --- Cluster [VC] V: Virgo, C: Coma/A1367 supercluster
3- 10 A8 --- Gal Galaxy designation (1)
12- 16 A5 --- Memb The membership to a cluster or supercluster (2)
18- 20 A3 --- MType Morphological type as given in the VCC or in
Gavazzi & Boselli (1996ApL&C..35....1G 1996ApL&C..35....1G)
22- 26 F5.2 deg Theta Projected angular separation from the nearest
cluster center
28- 32 F5.2 mag Hmag Asymptotic H band magnitude, as described in
Gavazzi et al. (2000, Cat. J/A+A/361/863)
34- 36 I3 Mpc Dist Distance (3)
38- 42 F5.2 --- Defgas ? Gas deficiency parameter (4)
44- 46 I3 0.1nm EW Halpha+[NII] equivalent width
48- 53 F6.2 [mW/m2] Log(FHa) Log of the Halpha flux deblended from the [NII]
contribution and corrected for internal
extinction as in Boselli et al.
(2001AJ....121..753B 2001AJ....121..753B).
55- 56 A2 --- Ref Reference to the Halpha data (5)
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Note (1): Galaxy designations:
VCC: Virgo Cluster Catalogue, Binggeli et al., 1985,
Cat. J/AJ/90/1681, for Virgo galaxies
Z: CGCG catalogue Zwicky et al., 1961-68, see Cat. VII/190, for
Coma supercluster galaxies.
Note (2): Defined as in Gavazzi et al. (1999MNRAS.304..595G 1999MNRAS.304..595G) for Virgo
and Gavazzi et al. (1999A&AS..136..227G 1999A&AS..136..227G) for the Coma/A1367 supercluster.
A1367 : Member of A1367 cluster
Coma : Member of Coma cluster
Grp : Member of a group
Iso : Isolated
Prs : Pairs
VA : Member of Virgo A
VB : Member of Virgo B
VE : Member of Virgo E
VM : Member of Virgo M
VN : Member of Virgo N
VS : Member of Virgo S
VW : Member of Virgo W
VZ : Member of Virgo Z
Note (3): We assume 17 Mpc for Virgo A, N, S, E, 23 Mpc for Virgo B and 32 Mpc
for Virgo W, M, as given in Gavazzi et al. (1999MNRAS.304..595G 1999MNRAS.304..595G),
96 Mpc for Coma, 91 Mpc for A1367. For galaxies not belonging to the
clusters, the distance is determined from the redshift using H0=75km/s/Mpc.
Note (4): Logarithmic difference between the gas content of isolated
galaxies of a given Hubble type and the measured gas content.
Note (5): References:
1: Kennicutt & Kent, 1983AJ.....88.1094K 1983AJ.....88.1094K
2: Kennicutt et al., 1994ApJ...435...22K 1994ApJ...435...22K
3: Gavazzi et al., 1991AJ....101.1207G 1991AJ....101.1207G
4: Romanishin, 1990AJ....100..373R 1990AJ....100..373R
5: Gavazzi et al., 1998AJ....115.1745G 1998AJ....115.1745G
6: Almoznino & Brosch, 1998MNRAS.298..920A 1998MNRAS.298..920A
7: Boselli & Gavazzi, 2002A&A...386..124B 2002A&A...386..124B, Paper II
8: Moss et al., 1998MNRAS.300..205M 1998MNRAS.300..205M
9: Heller et al., 1999MNRAS.304....8H 1999MNRAS.304....8H
10: Usui et al., 1998AJ....116.2166U 1998AJ....116.2166U
11: Gavazzi et al., 2002A&A...386..114G 2002A&A...386..114G, Paper I
12: Boselli et al., 2002A&A...386..134B 2002A&A...386..134B, Paper III
13: Koopmann et al., 2001ApJS..135..125K 2001ApJS..135..125K
14: Iglesias et al., 2002, Cat. J/A+A/384/383
TW: This work.
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History:
From electronic version of the journal
References:
Gavazzi et al., Paper I 2002A&A...386..114G 2002A&A...386..114G
Boselli & Gavazzi, Paper II 2002A&A...386..124B 2002A&A...386..124B
Boselli et al., Paper III 2002A&A...386..134B 2002A&A...386..134B
(End) James Marcout, Patricia Bauer [CDS] 20-Jan-2003