J/ApJ/841/7 Spectroscopic obs & members of ZwCl 2341+0000 (Benson+, 2017)
MC2: a deeper look at ZwCl 2341.1+0000 with Bayesian galaxy clustering and
weak lensing analyses.
Benson B., Wittman D.M., Golovich N., Jee M.J., van Weeren R.J., Dawson W.A.
<Astrophys. J., 841, 7 (2017)>
=2017ApJ...841....7B 2017ApJ...841....7B
ADC_Keywords: Clusters, galaxy ; Galaxies, optical ; Spectroscopy ; Redshifts
Keywords: galaxies: clusters: general ; gravitational lensing: weak
galaxies: clusters: individual (ZwCl 2341.1+0000)
Abstract:
ZwCl 2341.1+0000, a merging galaxy cluster with disturbed X-ray
morphology and widely separated (∼3Mpc) double radio relics, was
thought to be an extremely massive (10-30x1014M☉) and complex
system, with little known about its merger history. We present JVLA
2-4GHz observations of the cluster, along with new spectroscopy from
our Keck/DEIMOS survey, and apply Gaussian Mixture Modeling to the
three-dimensional distribution of 227 confirmed cluster galaxies.
After adopting the Bayesian Information Criterion to avoid
overfitting, which we discover can bias high the total dynamical mass
estimates, we find that a three-substructure model with a total
dynamical mass estimate of 9.39±0.81x1014M☉ is favored. We
also present deep Subaru imaging and perform the first weak lensing
analysis on this system, obtaining a weak lensing mass estimate of
5.57±2.47x1014M☉. This is a more robust estimate because it
does not depend on the dynamical state of the system, which is
disturbed due to the merger. Our results indicate that ZwCl2341.1+0000
is a multiple merger system comprised of at least three substructures,
with the main merger that produced the radio relics occurring near the
plane of the sky, and a younger merger in the north occurring closer
to the line of sight. Dynamical modeling of the main merger reproduces
observed quantities (relic positions and polarizations, subcluster
separation and radial velocity difference), if the merger axis angle
of ∼10-6+34 degrees and the collision speed at pericenter is
∼1900-200+300km/s.
Description:
We observed ZwCl 2341.1+0000 using the Subaru Prime Focus Camera
(SuprimeCam) with the 8.2 m Subaru telescope at the National
Astronomical Observatory of Japan on Maunakea (P.I. D. Wittman). We
carried out the observations over two nights (2013 February 23-24) in
the g' and r' bands.
We conducted a spectroscopic survey of ZwCl 2341.1+0000 with the
DEIMOS instrument on the Keck II 10m telescope over two separate
observing runs, with two observations performed on 2013 July 14 and
one performed on 2013 September 5.
ZwCl 2341.1+0000 was observed with the Karl G. Jansky Very Large Array
(JVLA) in the ∼2-4GHz on 2015 Oct 19 and 2014 Oct 09.
Objects:
---------------------------------------------------------------
RA (ICRS) DE Designation(s)
---------------------------------------------------------------
23 43 40.57 +00 18 18.9 ZwCl 2341.1+0000 = ZwCl 2341+0000
---------------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . this file
table2.dat 42 227 Spectroscopic cluster member catalog
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
J/ApJ/702/1230 : Rotation measure image of the sky (Taylor+, 2009)
J/MNRAS/434/772 : Velocities in ZwCl2341.1+0000 field (Boschin+, 2013)
J/ApJ/772/131 : Musket Ball Cluster redshift catalog (Dawson, 2013)
J/ApJ/805/143 : MC2: redshift analysis of CIZA J2242.8+5301 (Dawson+, 2015)
J/ApJ/813/77 : Galaxy clusters: radio halos, relics & param. (Yuan+, 2015)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh [23] Right Ascension (J2000) (hours)
4- 5 I2 min RAm [43/44] Right Ascension (J2000) (minutes)
7- 11 F5.2 s RAs Right Ascension (J2000) (seconds)
13- 13 A1 --- DE- [+] Declination (J2000) (sign)
14- 15 I2 deg DEd [0] Declination (J2000) (degrees)
17- 18 I2 arcmin DEm [10/25] Declination (J2000) (minutes)
20- 24 F5.2 arcsec DEs Declination (J2000) (seconds)
26- 33 F8.6 --- z [0.2587/0.2836] Redshift
35- 42 F8.6 --- e_z [/0.0002] Uncertainty on Redshift
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Jan-2018