### Abstract

We have measured the angular and spatial clustering of 671 K < 18.40, R - K > 5 extremely red objects (EROs) from a 0.98 deg^{2} subregion of the NOAO Deep Wide-Field Survey (NDWFS). Our study covers nearly 5 times the area and has twice the sample size of any previous ERO clustering study. The wide field of view and B_{W}RIK passbands of the NDWFS allow us to place improved constraints on the clustering of z ∼ 1 EROs. We find that the angular clustering of EROs is slightly weaker than in previous measurements, and ω(1′) = 0.25 ± 0.05 for K < 18.40 EROs. We find no significant correlation of ERO spatial clustering with redshift, apparent color, or absolute magnitude, although given the uncertainties, such correlations remain plausible. We find that the spatial clustering of K < 18.40, R - K > 5 EROs is well approximated by a power law, with r_{0} = 9.7 ± 1.1 h^{-1} Mpc in comoving coordinates. This is comparable to the clustering of ∼4L* early-type galaxies at z < 1 and is consistent with the brightest EROs being the progenitors of the most massive elliptical galaxies. There is evidence of the angular clustering of EROs decreasing with increasing apparent magnitude, when NDWFS measurements of ERO clustering are combined with those from the literature. Unless the redshift distribution of K≳20 EROs is very broad, the spatial clustering of EROs decreases from r_{0} = 9.7 ± 1.1 A^{-1} Mpc for K < 18.40 to r_{0} ∼ 7.5 A^{-1} Mpc for K≳20 EROs.

Original language | English (US) |
---|---|

Pages (from-to) | 41-52 |

Number of pages | 12 |

Journal | Astrophysical Journal |

Volume | 621 |

Issue number | 1 I |

DOIs | |

State | Published - Mar 1 2005 |

Externally published | Yes |

### Fingerprint

### Keywords

- Cosmology: Observations
- Galaxies: Elliptical and lenticular, cd
- Galaxies: High-redshift
- Large-scale structure of universe

### ASJC Scopus subject areas

- Space and Planetary Science

### Cite this

*Astrophysical Journal*,

*621*(1 I), 41-52. https://doi.org/10.1086/427472

**The clustering of extragalactic extremely red objects.** / Brown, Michael J I; Jannuzi, Buell Tomasson; Dey, Arjun; Tiede, Glenn P.

Research output: Contribution to journal › Article

*Astrophysical Journal*, vol. 621, no. 1 I, pp. 41-52. https://doi.org/10.1086/427472

}

TY - JOUR

T1 - The clustering of extragalactic extremely red objects

AU - Brown, Michael J I

AU - Jannuzi, Buell Tomasson

AU - Dey, Arjun

AU - Tiede, Glenn P.

PY - 2005/3/1

Y1 - 2005/3/1

N2 - We have measured the angular and spatial clustering of 671 K < 18.40, R - K > 5 extremely red objects (EROs) from a 0.98 deg2 subregion of the NOAO Deep Wide-Field Survey (NDWFS). Our study covers nearly 5 times the area and has twice the sample size of any previous ERO clustering study. The wide field of view and BWRIK passbands of the NDWFS allow us to place improved constraints on the clustering of z ∼ 1 EROs. We find that the angular clustering of EROs is slightly weaker than in previous measurements, and ω(1′) = 0.25 ± 0.05 for K < 18.40 EROs. We find no significant correlation of ERO spatial clustering with redshift, apparent color, or absolute magnitude, although given the uncertainties, such correlations remain plausible. We find that the spatial clustering of K < 18.40, R - K > 5 EROs is well approximated by a power law, with r0 = 9.7 ± 1.1 h-1 Mpc in comoving coordinates. This is comparable to the clustering of ∼4L* early-type galaxies at z < 1 and is consistent with the brightest EROs being the progenitors of the most massive elliptical galaxies. There is evidence of the angular clustering of EROs decreasing with increasing apparent magnitude, when NDWFS measurements of ERO clustering are combined with those from the literature. Unless the redshift distribution of K≳20 EROs is very broad, the spatial clustering of EROs decreases from r0 = 9.7 ± 1.1 A-1 Mpc for K < 18.40 to r0 ∼ 7.5 A-1 Mpc for K≳20 EROs.

AB - We have measured the angular and spatial clustering of 671 K < 18.40, R - K > 5 extremely red objects (EROs) from a 0.98 deg2 subregion of the NOAO Deep Wide-Field Survey (NDWFS). Our study covers nearly 5 times the area and has twice the sample size of any previous ERO clustering study. The wide field of view and BWRIK passbands of the NDWFS allow us to place improved constraints on the clustering of z ∼ 1 EROs. We find that the angular clustering of EROs is slightly weaker than in previous measurements, and ω(1′) = 0.25 ± 0.05 for K < 18.40 EROs. We find no significant correlation of ERO spatial clustering with redshift, apparent color, or absolute magnitude, although given the uncertainties, such correlations remain plausible. We find that the spatial clustering of K < 18.40, R - K > 5 EROs is well approximated by a power law, with r0 = 9.7 ± 1.1 h-1 Mpc in comoving coordinates. This is comparable to the clustering of ∼4L* early-type galaxies at z < 1 and is consistent with the brightest EROs being the progenitors of the most massive elliptical galaxies. There is evidence of the angular clustering of EROs decreasing with increasing apparent magnitude, when NDWFS measurements of ERO clustering are combined with those from the literature. Unless the redshift distribution of K≳20 EROs is very broad, the spatial clustering of EROs decreases from r0 = 9.7 ± 1.1 A-1 Mpc for K < 18.40 to r0 ∼ 7.5 A-1 Mpc for K≳20 EROs.

KW - Cosmology: Observations

KW - Galaxies: Elliptical and lenticular, cd

KW - Galaxies: High-redshift

KW - Large-scale structure of universe

UR - http://www.scopus.com/inward/record.url?scp=17444422554&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=17444422554&partnerID=8YFLogxK

U2 - 10.1086/427472

DO - 10.1086/427472

M3 - Article

AN - SCOPUS:17444422554

VL - 621

SP - 41

EP - 52

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1 I

ER -