J/A+A/602/A20 Abell 315 spectroscopic dataset (Biviano+, 2017)
Abell 315: reconciling cluster mass estimates from kinematics, X-ray, and
lensing.
Biviano A., Popesso P., Dietrich J.P., Zhang Y.-Y., Erfanianfar G.,
Romaniello M., Sartoris B.
<Astron. Astrophys. 602, A20 (2017)>
=2017A&A...602A..20B 2017A&A...602A..20B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, optical ; Redshifts
Keywords: galaxies: clusters: individual: Abell 315 -
galaxies: kinematics and dynamics
Abstract:
Determination of cluster masses is a fundamental tool for cosmology.
Comparing mass estimates obtained by different probes allows to
understand possible systematic uncertainties. Aims. The cluster Abell
315 is an interesting test case, since it has been claimed to be
underluminous in X-ray for its mass (determined via kinematics and
weak lensing). We have undertaken new spectroscopic observations with
the aim of improving the cluster mass estimate, using the distribution
of galaxies in projected phase space.
We identified cluster members in our new spectroscopic sample. We
estimated the cluster mass from the projected phase-space distribution
of cluster members using the MAMPOSSt method. In doing this estimate
we took into account the presence of substructures that we were able
to identify.
We identify several cluster substructures. The main two have an
overlapping spatial distribution, suggesting a (past or ongoing)
collision along the line-of-sight. After accounting for the presence
of substructures, the mass estimate of Abell 315 from 14 kinematics is
reduced by a factor 4, down to M200=0.8-0.4+0.610+14M☉. We
also find evidence that the cluster mass concentration is unusually
low, c200=r200/r-2<1. Using our new estimate of c200 we revise
the weak lensing mass estimate down to
M200=1.8-0.9+1.710+14M☉. Our new mass estimates are in
agreement with that derived from the cluster X-ray luminosity via a
scaling relation, M200=0.9±0.2*1014M☉.
Abell 315 no longer belongs to the class of X-ray underluminous
clusters. Its mass estimate was inflated by the presence of an
undetected subcluster in collision with the main cluster. Whether the
presence of undetected line-of-sight structures can be a general
explanation for all X-ray underluminous clusters remains to be
explored using a statistically significant sample.
Description:
Abell 315 was observed at the European Southern Observatory (ESO) Very
Large Telescope (VLT) with the VIsible MultiObject Spectrograph
(VIMOS).
The VIMOS data were acquired using 8 separate pointings, plus 2
additional pointings required to provide the needed redundancy within
the central region and to cover the gaps between the VIMOS quadrants.
Catalog of galaxies with redshifts in the region of the cluster
Abell 315, with flags indicating whether these galaxies are members of
the cluster, members of substructures within the cluster, and with
probabilities for the cluster members to belong to the main cluster
structure.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 52 946 Redshift and membership for 946 galaxies in the
Abell 315 cluster field
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Galaxy Galaxy identification number
7- 8 I2 h RAh Right Ascension (J2000)
10- 11 I2 min RAm Right Ascension (J2000)
13- 17 F5.2 s RAs Right Ascension (J2000)
19 A1 --- DE- Declination sign (J2000)
21 I1 deg DEd Declination (J2000)
23- 24 I2 arcmin DEm Declination (J2000)
26- 29 F4.1 arcsec DEs Declination (J2000)
31- 36 F6.4 --- zSDSS ?=0 Heliocentric redshift from SDSS
38- 43 F6.4 --- zVIMOS ?=0 Heliocentric redshift from VIMOS
45 I1 --- Member [0/1] Cluster membership flag
47 I1 --- Subst [0/1] Cluster substructure flag
49- 52 F4.2 --- Prob Main cluster membership probability
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Acknowledgements:
Andrea Biviano, biviano(at)oats.inaf.it
(End) Andrea Biviano [INAF-Trieste], Patricia Vannier [CDS] 24-Mar-2017