---
_id: '17750'
abstract:
- lang: eng
text: We present the discovery of three new quasars at z>6 in 1300 deg^2 of SDSS
imaging data, J114816.64+525150.3 (z=6.43), J104845.05+463718.3 (z=6.23) and J163033.90+401209.6
(z=6.05). The first two objects have weak Ly alpha emission lines; their redshifts
are determined from the positions of the Lyman break. They are only accurate to
0.05 and could be affected by the presence of broad absorption line systems. The
last object has a Ly alpha strength more typical of lower redshift quasars. Based
on a sample of six quasars at z>5.7 that cover 2870 deg^2 presented in this paper
and in Paper I, we estimate the comoving density of luminous quasars at z 6 and
M_{1450} < -26.8 to be (8 +/- 3)x10^{-10} Mpc^{-3} (for H_0 = 50 km/s/Mpc, Omega
= 1). HST imaging of two z>5.7 quasars and high-resolution ground-based images
(seeing 0.4'') of three additional z>5.7 quasars show that none of them is gravitationally
lensed. The luminosity distribution of the high-redshfit quasar sample suggests
the bright end slope of the quasar luminosity function at z 6 is shallower than
Psi L^{-3.5} (2-sigma), consistent with the absence of strongly lensed objects.
article_processing_charge: No
article_type: original
author:
- first_name: Xiaohui
full_name: Fan, Xiaohui
last_name: Fan
- first_name: Michael A.
full_name: Strauss, Michael A.
last_name: Strauss
- first_name: Donald P.
full_name: Schneider, Donald P.
last_name: Schneider
- first_name: Robert H.
full_name: Becker, Robert H.
last_name: Becker
- first_name: Richard L.
full_name: White, Richard L.
last_name: White
- first_name: Zoltán
full_name: Haiman, Zoltán
id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
last_name: Haiman
- first_name: Michael
full_name: Gregg, Michael
last_name: Gregg
- first_name: Laura
full_name: Pentericci, Laura
last_name: Pentericci
- first_name: Eva K.
full_name: Grebel, Eva K.
last_name: Grebel
- first_name: Vijay K.
full_name: Narayanan, Vijay K.
last_name: Narayanan
- first_name: Yeong-Shang
full_name: Loh, Yeong-Shang
last_name: Loh
- first_name: Gordon T.
full_name: Richards, Gordon T.
last_name: Richards
- first_name: James E.
full_name: Gunn, James E.
last_name: Gunn
- first_name: Robert H.
full_name: Lupton, Robert H.
last_name: Lupton
- first_name: Gillian R.
full_name: Knapp, Gillian R.
last_name: Knapp
- first_name: Željko
full_name: Ivezić, Željko
last_name: Ivezić
- first_name: W. N.
full_name: Brandt, W. N.
last_name: Brandt
- first_name: Matthew
full_name: Collinge, Matthew
last_name: Collinge
- first_name: Lei
full_name: Hao, Lei
last_name: Hao
- first_name: Daniel
full_name: Harbeck, Daniel
last_name: Harbeck
- first_name: Francisco
full_name: Prada, Francisco
last_name: Prada
- first_name: Joop
full_name: Schaye, Joop
last_name: Schaye
- first_name: Iskra
full_name: Strateva, Iskra
last_name: Strateva
- first_name: Nadia
full_name: Zakamska, Nadia
last_name: Zakamska
- first_name: Scott
full_name: Anderson, Scott
last_name: Anderson
- first_name: Jon
full_name: Brinkmann, Jon
last_name: Brinkmann
- first_name: Neta A.
full_name: Bahcall, Neta A.
last_name: Bahcall
- first_name: Don Q.
full_name: Lamb, Don Q.
last_name: Lamb
- first_name: Sadanori
full_name: Okamura, Sadanori
last_name: Okamura
- first_name: Alex
full_name: Szalay, Alex
last_name: Szalay
- first_name: Donald G.
full_name: York, Donald G.
last_name: York
citation:
ama: Fan X, Strauss MA, Schneider DP, et al. A survey of z > 5.7 quasars in
the Sloan Digital Sky Survey. II. Discovery of three additional quasars at z >
6. The Astronomical Journal. 2003;125(4):1649-1659. doi:10.1086/368246
apa: Fan, X., Strauss, M. A., Schneider, D. P., Becker, R. H., White, R. L., Haiman,
Z., … York, D. G. (2003). A survey of z > 5.7 quasars in the Sloan Digital
Sky Survey. II. Discovery of three additional quasars at z > 6. The Astronomical
Journal. American Astronomical Society. https://doi.org/10.1086/368246
chicago: Fan, Xiaohui, Michael A. Strauss, Donald P. Schneider, Robert H. Becker,
Richard L. White, Zoltán Haiman, Michael Gregg, et al. “A Survey of z > 5.7
Quasars in the Sloan Digital Sky Survey. II. Discovery of Three Additional Quasars
at z > 6.” The Astronomical Journal. American Astronomical Society,
2003. https://doi.org/10.1086/368246.
ieee: X. Fan et al., “A survey of z > 5.7 quasars in the Sloan Digital
Sky Survey. II. Discovery of three additional quasars at z > 6,” The Astronomical
Journal, vol. 125, no. 4. American Astronomical Society, pp. 1649–1659, 2003.
ista: Fan X, Strauss MA, Schneider DP, Becker RH, White RL, Haiman Z, Gregg M, Pentericci
L, Grebel EK, Narayanan VK, Loh Y-S, Richards GT, Gunn JE, Lupton RH, Knapp GR,
Ivezić Ž, Brandt WN, Collinge M, Hao L, Harbeck D, Prada F, Schaye J, Strateva
I, Zakamska N, Anderson S, Brinkmann J, Bahcall NA, Lamb DQ, Okamura S, Szalay
A, York DG. 2003. A survey of z > 5.7 quasars in the Sloan Digital Sky Survey.
II. Discovery of three additional quasars at z > 6. The Astronomical Journal.
125(4), 1649–1659.
mla: Fan, Xiaohui, et al. “A Survey of z > 5.7 Quasars in the Sloan Digital
Sky Survey. II. Discovery of Three Additional Quasars at z > 6.” The Astronomical
Journal, vol. 125, no. 4, American Astronomical Society, 2003, pp. 1649–59,
doi:10.1086/368246.
short: X. Fan, M.A. Strauss, D.P. Schneider, R.H. Becker, R.L. White, Z. Haiman,
M. Gregg, L. Pentericci, E.K. Grebel, V.K. Narayanan, Y.-S. Loh, G.T. Richards,
J.E. Gunn, R.H. Lupton, G.R. Knapp, Ž. Ivezić, W.N. Brandt, M. Collinge, L. Hao,
D. Harbeck, F. Prada, J. Schaye, I. Strateva, N. Zakamska, S. Anderson, J. Brinkmann,
N.A. Bahcall, D.Q. Lamb, S. Okamura, A. Szalay, D.G. York, The Astronomical Journal
125 (2003) 1649–1659.
date_created: 2024-09-06T09:38:08Z
date_published: 2003-04-01T00:00:00Z
date_updated: 2024-09-30T07:33:02Z
day: '01'
doi: 10.1086/368246
extern: '1'
intvolume: ' 125'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1086/368246
month: '04'
oa: 1
oa_version: Published Version
page: 1649-1659
publication: The Astronomical Journal
publication_identifier:
issn:
- 0004-6256
- 1538-3881
publication_status: published
publisher: American Astronomical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: A survey of z > 5.7 quasars in the Sloan Digital Sky Survey. II. Discovery
of three additional quasars at z > 6
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 125
year: '2003'
...