Access to Astronomical Catalogues

← Click to display the menu
VII/256       Groups of Galaxies from CfA2 Redshift Survey  (Mahtessian++, 2010)

The List of Groups of Galaxies Based on CfA2 Redshift Survey. Mahtessian A.P., Movsessian V.G. <Astrophysics, 53, 70 (2010)> =2010Ap.....53...70M =2010Afz....53...83M
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Magnitudes ; Radial velocities ; Velocity dispersion Description: The catalog contains statistically homogeneous and physically well graunded groups of galaxies based on the CfA2 redshift survey (Cat. J/ApJS/121/287) in the area of space 1000km/s≤cz≤15000km/s, |bII|≥20°. For identification of groups we used a modification of a friends of friends (FoF) method. Principles of friendship and definition of values of presented there free parameters described in Mahtessian (1988Afz....28..255M, 1997Ap.....40..285M). There are 1971 groups with 2 or more members, for a total of 6787 members (46.3%); 765 of the groups have 3 or more members with 4375 galaxies (28.1%). The others 8790 (56.4%) galaxies make a sample of "single" galaxies. The catalog includes group numbers, numbers of members, equatorial coordinates, Virgo-centric radial velocities, line-of-sight-velocity dispersions, integrated group luminosities, and relative quantity of false members. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 77 6787 Data of groups members table2.dat 69 1971 Mean parameters of groups
See also: J/ApJS/121/287 : The CfA redshift survey (CfA2S) catalog (Huchra+, 1999) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 4 I4 --- Group Number of group 6- 16 A11 --- Galaxy Galaxy name, as in CfA2 (Cat. J/ApJS/121/287) 19- 20 I2 h RAh Right ascension (1950) 22- 25 F4.1 min RAm [0/60] Right ascension (1950) 27 A1 --- DE- Declination sign (1950) 28- 29 I2 deg DEd Declination (1950) 31- 32 I2 arcmin DEm [0/60] Declination (1950) 34- 38 F5.2 mag magc Apparent magnitude of galaxy corrected from galactic absorption (Sandage, 1973ApJ...183..711S) and by K damping (Yang et al., 2005MNRAS.356.1293Y.) 40- 44 I5 km/s RVc Virgo-centric radial velocities of galaxy (Mahtessian, 1997Ap.....40..285M) 46- 50 A5 --- T Morphological type of galaxy by CfA2 (99 means, that the type is unknown) 52- 56 I5 km/s RVC Radial velocities of galaxy relative to the group centre 58- 61 F4.2 Mpc RC Projected distance of galaxy to group centre 63- 68 F6.2 mag MAG Absolute magnitude of galaxy 70- 77 E8.3 solLum Lum Luminosity of galaxy
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 4 I4 --- Group Group number 6- 7 I2 h RAh A mean right ascension of group (1950) 9- 12 F4.1 min RAm [0/60] A mean right ascension of group (1950) 14 A1 --- DE- Declination sign (1950) 15- 16 I2 deg DEd A mean declination of group (1950) 18- 19 I2 arcmin DEm [0/60] A mean declination of group (1950) 21- 23 I3 --- Ng Number of visible members of group 25- 29 I5 km/s VG Mean Virgocentric velocity of group 31- 33 I3 km/s sigma A dispersion of radial velocity of members of group 35- 39 F5.3 Mpc Rmean Mean distance of members of group from its centre 41- 45 F5.3 Mpc Rmax Group radius: the greatest distance of members of group from its centre 47- 54 E8.3 solLum Lobs Total luminosity of visible members of group 56- 63 E8.3 solLum Ltot Total luminosity both visible, and invisible members of group 65- 69 F5.3 % FIC Relative quantity of false members of groups in percentage (Mahtessian, 1998Ap.....41..308M)
Acknowledgements: A.P. Mahtessian, amahtes(at)bao.sci.am References: Mahtessian, Astrofizics, 28, 255, 1988, 1988Afz....28..255M (Ap, 28, 150) Mahtessian, Astrofizics, 40, 45, 1997, 1997Ap.....40...25M Mahtessian, Astrofizics, 41, 473, 1998, 1998Ap.....41..308M Mahtessian, Astrofizics, 50, 535, 2007, 2007Ap.....50..440M
(End) Patricia Vannier [CDS] 18-Dec-2009
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

catalogue service

© UDS/CNRS

Contact