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J/A+A/421/59      Equivalent widths of VMF73 and VMF74 galaxies  (Gerken+, 2004)

Star formation activity of intermediate redshift cluster galaxies out to the infall regions. Gerken B., Ziegler B.L., Balogh M.L., Gilbank D.G., Fritz A., Jaeger K. <Astron. Astrophys. 421, 59 (2004)> =2004A&A...421...59G
ADC_Keywords: Galaxies, optical ; Equivalent widths ; Redshifts Keywords: galaxies: clusters: individual: RXJ094330.7+164002 - galaxies: clusters: individual: RXJ094344.9+164448 - galaxies: evolution - galaxies: distances and redshifts - galaxies: stellar content Abstract: We present a spectroscopic analysis of two galaxy clusters out to ∼4Mpc at z∼0.2. The two clusters VMF73 and VMF74 identified by Vikhlinin et al. (1998, Cat. J/ApJ/502/558) were observed with MOSCA at the Calar Alto 3.5m telescope. Both clusters lie in the ROSAT PSPC field R285 and were selected from the X-ray Dark Cluster Survey (Gilbank et al., 2004MNRAS.348..551G) that provides optical V- and I-band data. VMF73 and VMF74 are located at respective redshifts of z=0.25 and z=0.18 with velocity dispersions of 671km/s and 442km/s, respectively. The spectroscopic observations reach out to ∼2.5 virial radii. Line strength measurements of the emission lines H_alpha and [OII]3727 are used to assess the star formation activity of cluster galaxies which show radial and density dependences. The mean and median of both line strength distributions as well as the fraction of star forming galaxies increase with increasing clustercentric distance and decreasing local galaxy density. Except for two galaxies with strong H_alpha and [OII] emission, all of the cluster galaxies are normal star forming or passive galaxies. Our results are consistent with other studies that show the truncation in star formation occurs far from the cluster centre. Description: J2000 coordinates, redshifts and equivalent widths of Hα and [OII]3727 are presented for a sample of 79 galaxies in the clusters VMF73 and VMF74 at respective redshifts of z=0.25 and z=0.18. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 88 79 J2000 coordinates, redshifts and Hα and [OII]3727 equivalent widths of 79 galaxies in VMF73 and VMF74
See also: J/ApJ/502/558 : Catalog of ROSAT galaxy clusters (Vikhlinin+ 1998) Byte-by-byte Description of file: tablea1.dat
Bytes Format Units Label Explanations
1- 8 A8 --- ID Galaxy spectrum ID number 11 I1 h RAh Right ascension (J2000) 13- 14 I2 min RAm Right ascension (J2000) 16- 21 F6.3 s RAs Right ascension (J2000) 23 A1 --- DE- Declination sing (J2000) 24- 25 I2 deg DEd Declination (J2000) 27- 28 I2 arcmin DEm Declination (J2000) 30- 34 F5.2 arcsec DEs Declination (J2000) 36- 41 F6.4 --- z Spectroscopic redshift 44- 51 F8.4 0.1nm EWHa ? Halpha equivalent width (1) 56- 61 F6.4 0.1nm e_EWHa ? Error of Hα equivalent width 65- 71 F7.4 0.1nm EWOII Equivalent width of [OII]3727 76- 81 F6.4 0.1nm e_EWOII Error of [OII]3727 equivalent width 83- 87 A5 --- Cl Corresponding galaxy cluster (VMF73 or VMF74) (2)
Note (1): The spectrum r2851_14 is corrupted in the blue which made an [OII] measurement in this galaxy impossible. Note (2): VMF73 and VMF74 identified as [VMF98] 73 and [VMF98] 74 in Simbad
Acknowledgements: Betina Gerren
(End) Bettina Gerken [Oxford University, UK], Patricia Vannier [CDS] 29-Apr-2004
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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