Witnessing the hierarchical assembly of the brightest cluster galaxy in a cluster at z = 1.26

Toru Yamada; Yohei Koyama; Fumiaki Nakata; Masaru Kajisawa; Ichi Tanaka; Tadayuki Kodama; Sadanori Okamura; Roberto De Propris

doi:10.1086/344400

Witnessing the hierarchical assembly of the brightest cluster galaxy in a cluster at z = 1.26

Toru Yamada, Yohei Koyama, Fumiaki Nakata, Masaru Kajisawa, Ichi Tanaka, Tadayuki Kodama, Sadanori Okamura, Roberto De Propris

SCI - Astronomy

Research output: Contribution to journal › Article › peer-review

17 Citations (Scopus)

Abstract

We have obtained a new high-resolution K′-band image of the central region of the rich X-ray cluster RX J0848.9+4452 at z = 1.26. We found that the brightest cluster galaxy (BCG) in the cluster is clearly separated into two distinct objects. Whereas the optical to near-infrared colors of the objects are consistent with the predictions of passive evolution models for galaxies formed at high redshift, the luminosities of the two galaxies are both considerably fainter than predicted by passive evolution of BCGs in low- and intermediate-redshift clusters. We argue that this is evidence of an ongoing merger of normal cluster elliptical galaxies to form the dominant galaxy in the core of RX J0848.9+4452. The two galaxies appear to point toward the nearby cluster CIG J0848+4453 and are aligned with the outer X-ray contour of their parent cluster, supporting a model of BCG formation by collimated infall along the surrounding large-scale structure.

Original language	English
Pages (from-to)	L89-L92
Journal	Astrophysical Journal
Volume	577
Issue number	2 II
DOIs	https://doi.org/10.1086/344400
Publication status	Published - 2002 Oct 1

Keywords

Galaxies: elliptical and lenticular, cD
Galaxies: evolution
Galaxies: formation

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

Access to Document

10.1086/344400

Cite this

@article{f9a534781db64d8b98554256ef52c3d5,

title = "Witnessing the hierarchical assembly of the brightest cluster galaxy in a cluster at z = 1.26",

abstract = "We have obtained a new high-resolution K′-band image of the central region of the rich X-ray cluster RX J0848.9+4452 at z = 1.26. We found that the brightest cluster galaxy (BCG) in the cluster is clearly separated into two distinct objects. Whereas the optical to near-infrared colors of the objects are consistent with the predictions of passive evolution models for galaxies formed at high redshift, the luminosities of the two galaxies are both considerably fainter than predicted by passive evolution of BCGs in low- and intermediate-redshift clusters. We argue that this is evidence of an ongoing merger of normal cluster elliptical galaxies to form the dominant galaxy in the core of RX J0848.9+4452. The two galaxies appear to point toward the nearby cluster CIG J0848+4453 and are aligned with the outer X-ray contour of their parent cluster, supporting a model of BCG formation by collimated infall along the surrounding large-scale structure.",

keywords = "Galaxies: elliptical and lenticular, cD, Galaxies: evolution, Galaxies: formation",

author = "Toru Yamada and Yohei Koyama and Fumiaki Nakata and Masaru Kajisawa and Ichi Tanaka and Tadayuki Kodama and Sadanori Okamura and {De Propris}, Roberto",

note = "Funding Information: This work is based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. This work is also based in part on observations with the NASA/ESA HST, obtained from the data archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. The Image Reduction and Analysis Facility used in this Letter is distributed by National Optical Astronomy Observatories, operated by AURA, Inc., under contract to the US National Science Foundation. T. K. acknowledges a JSPS postdoctoral research fellowship and the Daiwa-Adrian Prize 2001 for financial support.",

year = "2002",

month = oct,

day = "1",

doi = "10.1086/344400",

language = "English",

volume = "577",

pages = "L89--L92",

journal = "Astrophysical Journal",

issn = "0004-637X",

number = "2 II",

}

TY - JOUR

T1 - Witnessing the hierarchical assembly of the brightest cluster galaxy in a cluster at z = 1.26

AU - Yamada, Toru

AU - Koyama, Yohei

AU - Nakata, Fumiaki

AU - Kajisawa, Masaru

AU - Tanaka, Ichi

AU - Kodama, Tadayuki

AU - Okamura, Sadanori

AU - De Propris, Roberto

N1 - Funding Information: This work is based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. This work is also based in part on observations with the NASA/ESA HST, obtained from the data archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. The Image Reduction and Analysis Facility used in this Letter is distributed by National Optical Astronomy Observatories, operated by AURA, Inc., under contract to the US National Science Foundation. T. K. acknowledges a JSPS postdoctoral research fellowship and the Daiwa-Adrian Prize 2001 for financial support.

PY - 2002/10/1

Y1 - 2002/10/1

N2 - We have obtained a new high-resolution K′-band image of the central region of the rich X-ray cluster RX J0848.9+4452 at z = 1.26. We found that the brightest cluster galaxy (BCG) in the cluster is clearly separated into two distinct objects. Whereas the optical to near-infrared colors of the objects are consistent with the predictions of passive evolution models for galaxies formed at high redshift, the luminosities of the two galaxies are both considerably fainter than predicted by passive evolution of BCGs in low- and intermediate-redshift clusters. We argue that this is evidence of an ongoing merger of normal cluster elliptical galaxies to form the dominant galaxy in the core of RX J0848.9+4452. The two galaxies appear to point toward the nearby cluster CIG J0848+4453 and are aligned with the outer X-ray contour of their parent cluster, supporting a model of BCG formation by collimated infall along the surrounding large-scale structure.

AB - We have obtained a new high-resolution K′-band image of the central region of the rich X-ray cluster RX J0848.9+4452 at z = 1.26. We found that the brightest cluster galaxy (BCG) in the cluster is clearly separated into two distinct objects. Whereas the optical to near-infrared colors of the objects are consistent with the predictions of passive evolution models for galaxies formed at high redshift, the luminosities of the two galaxies are both considerably fainter than predicted by passive evolution of BCGs in low- and intermediate-redshift clusters. We argue that this is evidence of an ongoing merger of normal cluster elliptical galaxies to form the dominant galaxy in the core of RX J0848.9+4452. The two galaxies appear to point toward the nearby cluster CIG J0848+4453 and are aligned with the outer X-ray contour of their parent cluster, supporting a model of BCG formation by collimated infall along the surrounding large-scale structure.

KW - Galaxies: elliptical and lenticular, cD

KW - Galaxies: evolution

KW - Galaxies: formation

UR - http://www.scopus.com/inward/record.url?scp=0043241695&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0043241695&partnerID=8YFLogxK

U2 - 10.1086/344400

DO - 10.1086/344400

M3 - Article

AN - SCOPUS:0043241695

SN - 0004-637X

VL - 577

SP - L89-L92

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 2 II

ER -

Witnessing the hierarchical assembly of the brightest cluster galaxy in a cluster at z = 1.26

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this