TY - JOUR

T1 - Hubble space telescope weak-lensing study of the galaxy cluster xmmu j2235.3 - 2557 at z 1.4

T2 - A surprisingly massive galaxy cluster when the universe is one-third of its current age

AU - Jee, M. J.

AU - Rosati, P.

AU - Ford, H. C.

AU - Dawson, K. S.

AU - Lidman, C.

AU - Perlmutter, S.

AU - Demarco, R.

AU - Strazzullo, V.

AU - Mullis, C.

AU - Böhringer, H.

AU - Fassbender, R.

PY - 2009

Y1 - 2009

N2 - We present a weak-lensing analysis of the z ≃ 1.4 galaxy cluster XMMU J2235.3 - 2557, based on deep Advanced Camera for Surveys images. Despite the observational challenge set by the high redshift of the lens, we detect a substantial lensing signal at the ≳8σ level. This clear detection is enabled in part by the high mass of the cluster, which is verified by our both parametric and non-parametric estimation of the cluster mass. Assuming that the cluster follows a Navarro-Frenk-White mass profile, we estimate that the projected mass of the cluster within r = 1 Mpc is (8.5 1.7) × 10 14 M, where the error bar includes the statistical uncertainty of the shear profile, the effect of possible interloping background structures, the scatter in concentration parameter, and the error in our estimation of the mean redshift of the background galaxies. The high X-ray temperature 8.6 +1.3 -1.2 keV of the cluster recently measured with Chandra is consistent with this high lensing mass. When we adopt the 1σ lower limit as a mass threshold and use the cosmological parameters favored by the Wilkinson Microwave Anisotropy Probe 5-year (WMAP5) result, the expected number of similarly massive clusters at z ≳ 1.4 in the 11 square degree survey is N 5 × 10-3. Therefore, the discovery of the cluster within the survey volume is a rare event with a probability ≲1% and may open new scenarios in our current understanding of cluster formation within the standard cosmological model.

AB - We present a weak-lensing analysis of the z ≃ 1.4 galaxy cluster XMMU J2235.3 - 2557, based on deep Advanced Camera for Surveys images. Despite the observational challenge set by the high redshift of the lens, we detect a substantial lensing signal at the ≳8σ level. This clear detection is enabled in part by the high mass of the cluster, which is verified by our both parametric and non-parametric estimation of the cluster mass. Assuming that the cluster follows a Navarro-Frenk-White mass profile, we estimate that the projected mass of the cluster within r = 1 Mpc is (8.5 1.7) × 10 14 M, where the error bar includes the statistical uncertainty of the shear profile, the effect of possible interloping background structures, the scatter in concentration parameter, and the error in our estimation of the mean redshift of the background galaxies. The high X-ray temperature 8.6 +1.3 -1.2 keV of the cluster recently measured with Chandra is consistent with this high lensing mass. When we adopt the 1σ lower limit as a mass threshold and use the cosmological parameters favored by the Wilkinson Microwave Anisotropy Probe 5-year (WMAP5) result, the expected number of similarly massive clusters at z ≳ 1.4 in the 11 square degree survey is N 5 × 10-3. Therefore, the discovery of the cluster within the survey volume is a rare event with a probability ≲1% and may open new scenarios in our current understanding of cluster formation within the standard cosmological model.

KW - Cosmology: observations

KW - Dark matter

KW - Galaxies: clusters: individual (XMMU J2235.3-2557)

KW - Galaxies: high-redshift

KW - Gravitational lensing

KW - X-rays: galaxies: clusters

UR - http://www.scopus.com/inward/record.url?scp=70549110126&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/704/1/672

DO - 10.1088/0004-637X/704/1/672

M3 - Article

AN - SCOPUS:70549110126

SN - 0004-637X

VL - 704

SP - 672

EP - 686

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 1

ER -