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The Distance and Mass of the Galaxy Cluster Abell 1995 Derived from Sunyaev-Zeldovich Effect and X-Ray MeasurementsWe present multiwavelength observations of the Abell 1995 galaxy cluster. From an analysis of X-ray spectroscopy and imaging data, we derive the electron temperature, cluster core radius, and central electron number density. Using optical spectroscopy of 15 cluster members, we derive an accurate cluster redshift and velocity dispersion. Finally, the interferometric imaging of the Sunyaev-Zeldovich effect toward Abell 1995 at 28.5 GHz provides a measure of the integrated pressure through the cluster. The X-ray and Sunyaev-Zeldovich effect observations are combined to determine the angular diameter distance to the cluster of D(sub A) = 1294(sup +294 +438, sub -283 -458) Mpc (Statistical followed by systematic uncertainty), implying a Hubble constant of H(sub 0) = 52.2(sup +11.4 +18.5, sub -11.9 -17.7) km/s.Mpc for Omega(sub M) = 0.3 and Omega(sub lambda) = 0.7. We find a best-fit H(sub 0) of 46 km/s.Mpc for the Omega(sub M) = 1 and Omega(sub lambda) = 0 cosmology, and 48 km/s.Mpc for Omega(sub M) = 0.3 and Omega(sub lambda) = 0.0. The X-ray data are also used to derive a total cluster mass of M(sup HSE, sub tot)(r(sub 500)) = 5.18(sup +0.62, sub -0.48) x 10(exp 14)/h solar mass; the optical velocity dispersion yields an independent and consistent estimate of M(sup virial, sub tot)(r(sub 500)) = 6.35(sup +1.51, sub -1.19) X 10(exp 14) /h solar mass. Both of the total mass estimates are evaluated at a fiducial radius, r(sub 500) = 830 /h kpc, where the overdensity is 500 times the critical density. The total cluster mass is then combined with gas mass measurements to determine a cluster gas mass fraction of F(sub g) = 0.056(sup +0.010, sub -0.013) /h(sup 3/2) in combination with recent baryon density constraints, the measured gas mass fraction yields an upper limit on the mass density parameter of Omega(sub M) h(sup 1/2) <= 0.34(sup +/0.06, sub 0.05.
Document ID
20010038425
Acquisition Source
Marshall Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Patel, Sandeep K.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Joy, Marshall
(NASA Marshall Space Flight Center Huntsville, AL United States)
Carlstrom, John E.
(Chicago Univ. Chicago, IL United States)
Holder, Gilbert P.
(Chicago Univ. Chicago, IL United States)
Reese, Erik D.
(Chicago Univ. Chicago, IL United States)
Gomez, Percy L.
(Rutgers Univ. Piscataway, NJ United States)
Hughes, John P.
(Rutgers Univ. Piscataway, NJ United States)
Grego, Laura
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA United States)
Holzapfel, William L.
(California Univ. Berkeley, CA United States)
Date Acquired
August 20, 2013
Publication Date
September 20, 2000
Publication Information
Publication: Astrophysical Journal
Publisher: American Astronomical Society
Volume: 541
Subject Category
Astrophysics
Funding Number(s)
CONTRACT_GRANT: NSF AST-96-13998
CONTRACT_GRANT: NGT8-52863
CONTRACT_GRANT: NAG5-3432
CONTRACT_GRANT: NGT5-50173
CONTRACT_GRANT: NAG5-7986
CONTRACT_GRANT: NSF AST-96-13717
Distribution Limits
Public
Copyright
Other

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