J/AJ/115/6 Hercules supercluster kinematics (Barmby+ 1998)
Kinematics of the Hercules supercluster
Barmby P., Huchra J.P.
<Astron. J. 115, 6 (1998) + Erratum vol. 116, p. 1508>
=1998AJ....115....6B 1998AJ....115....6B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Radial velocities ; Photometry, CCD
Keywords: cosmology: observations - dark matter -
galaxies: clusters: individual (Hercules)
Abstract:
The Hercules supercluster consists of the Abell clusters A2147, A2151,
and A2152. Previous studies of the kinematics have been confounded by
the difficulty of correctly assigning galaxies to the individual
clusters, which are not well separated. Our study has a total of 468
available velocities for galaxies in the region, 175 of them new.
There are 414 galaxies in the supercluster, about 3 times the number
used in the previous supercluster study. We verify the existence of
the three individual clusters and compute their individual dynamical
parameters. We investigate several techniques for assigning galaxy
membership to clusters in this crowded field. We use the Kaye's
mixture model (Ashman, Bird, & Zepf, 1994AJ....108.2348A 1994AJ....108.2348A) algorithm to
separate the galaxies into clusters; we find that A2152 has a higher
mean velocity than previous studies have reported. A2147 and A2152
also have lower velocity dispersions: 821+68-55 and
715+81-61km/s, respectively. The assignment of galaxies to either
A2152 or A2147 requires velocity and position information. We study
the kinematics of the supercluster using the two-body formalism of
Beers, Geller, & Huchra
(1982ApJ...257...23B 1982ApJ...257...23B) and conclude that A2147 and A2151 are probably
bound to each other and that the supercluster as a whole may also be
bound. The mass of the supercluster, if bound, is
(7.6±2.0)x1015h-1M☉; with the supercluster luminosity,
(1.4±0.2)x1013h-2L☉, this yields
{OMEGA}=0.34±0.1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 72 458 *Galaxies in the Hercules supercluster
table1.tex 97 486 LaTeX Version of Table 1
table1.ps 72 1271 Postscript version of Table 1
refs.dat 80 33 References quoted in Table 1
table9.dat 45 16 CCD photometry for A2151 galaxies
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Note on table1.dat: the printed version of this table had several
errors, including typographical errors in coordinates, object
misidentifications, and duplicate entries (see "History" section below)
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See also:
VII/99 : Radial Velocities of Galaxies (Palumbo+ 1986)
VII/112 : RC2 Catalogue (de Vaucouleurs+ 1976)
VII/155 : RC3 Catalogue (de Vaucouleurs+ 1991)
VII/172 : First Byurakan Survey (FBS) (Markarian+, 1989)
J/A+AS/109/537 : Redshift survey of faint galaxies (Hopp+, 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Name Galaxy name
25- 26 I2 h RAh Right ascension (J2000.0)
28- 29 I2 min RAm Right ascension (J2000.0)
31- 35 F5.2 s RAs Right ascension (J2000.0)
37 A1 --- DE- Declination sign
38- 39 I2 deg DEd Declination (J2000.0)
41- 42 I2 arcmin DEm Declination (J2000.0)
44- 48 F5.2 arcsec DEs Declination (J2000.0)
51- 54 F4.1 mag Rmag R magnitude
58- 62 I5 km/s HV Heliocentric velocity
64- 66 I3 km/s e_HV rms uncertainty on HV
68 A1 --- MType Morphological type
71- 72 I2 --- r_HV [1/32] Velocity source, see refs.dat
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Galaxy name
17- 18 I2 h RAh Right ascension (J2000.0)
20- 21 I2 min RAm Right ascension (J2000.0)
23- 24 I2 s RAs Right ascension (J2000.0)
26 A1 --- DE- Declination sign
27- 28 I2 deg DEd Declination (J2000.0)
30- 31 I2 arcmin DEm Declination (J2000.0)
33- 34 I2 arcsec DEs Declination (J2000.0)
36- 40 F5.2 mag Bmag B magnitude
42- 45 F4.2 mag B-R B-R colour index
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- RefCode [1/32]+= Reference code
4- 80 A77 --- Text Text of reference (including the
19-digit bibcode)
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History:
* 05-Mar-1998: Copied from the electronic version of AJ
* 02-Jun-1998 (from Pauline Barmby, )
Table 1, Galaxies in the Hercules Supercluster, had several errors,
including typographical errors in coordinates, object
misidentifications, and duplicate entries.
We have corrected these errors and determined that they not do not
affect the conclusions of the paper. A corrected version of the table,
containing 458 galaxies with velocities (171 new velocities) is
available in the electronic version of the paper. We thank M. Schmitz
for bringing some of the errors to our attention.
* September 1998: Erratum published in AJ.
(End) Patricia Bauer [CDS] 05-Mar-1998