The physical nature of Lyα-emitting galaxies at z=3.1

被引:179
作者
Gawiser, E [1 ]
van Dokkum, PG
Gronwall, C
Ciardullo, R
Blanc, GA
Castander, FJ
Feldmeier, J
Francke, H
Franx, M
Haberzettl, L
Herrera, D
Hickey, T
Infante, L
Lira, P
Maza, J
Quadri, R
Richardson, A
Schawinski, K
Schirmer, M
Taylor, EN
Treister, E
Urry, CM
Virani, SN
机构
[1] Yale Univ, Dept Astron, New Haven, CT 06520 USA
[2] Yale Univ, Ctr Astron & Astrophys, New Haven, CT 06520 USA
[3] Univ Chile, Dept Astron, Santiago, Chile
[4] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA
[5] CSIC, Inst Estudis Espacials Catalunya, E-08034 Barcelona, Spain
[6] Natl Opt Astron Observ, Tucson, AZ 85726 USA
[7] Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands
[8] Ruhr Univ Bochum, Astron Inst, D-44780 Bochum, Germany
[9] Yale Univ, Dept Phys, New Haven, CT 06520 USA
[10] Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 22, Chile
[11] Univ Oxford, Oxford OX1 3RH, England
[12] Univ Bonn, Inst Astrophys & Extraterr Forsch, D-53121 Bonn, Germany
基金
美国国家科学基金会;
关键词
galaxies; high-redshift;
D O I
10.1086/504467
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We selected 40 candidate Ly alpha-emitting galaxies ( LAEs) at z similar or equal to 3.1 with observed-frame equivalent widths greater than 150 and inferred emission-line fluxes above 2.5 x 10(-17) ergs cm(-2) s(-1) from deep narrowband and broadband MUSYC images of the Extended Chandra Deep Field South. Covering 992 arcmin(2), this is the largest "blank field" surveyed for LAEs at z similar to 3, allowing an improved estimate of the space density of this population of ( 3 +/- 1) x 10(-4) h(70)(3) Mpc(-3). Spectroscopic follow-up of 23 candidates yielded 18 redshifts, all at z similar or equal to 3.1. Over 80% of the LAEs are dimmer in continuum magnitude than the typical Lyman break galaxy ( LBG) spectroscopic limit of R = 25.5 ( AB), with a median continuum magnitude R similar or equal to 27 and very blue continuum colors, V-z similar or equal to 0. Over 80% of the LAEs have the right UVR colors to be selected as LBGs, but only 10% also have R <= 25.5. Stacking the UBVRIzJK fluxes reveals that LAEs have stellar masses similar or equal to 5 x 10(8) h(70)(-2) M-circle dot and minimal dust extinction, A(V) less than or similar to 0.1. Inferred star formation rates are similar or equal to 6 h(70)(-2) M-circle dot yr(-1), yielding a cosmic star formation rate density of 2 x 10(-3) h(70) M-circle dot yr(-1) Mpc(-3). None of our LAE candidates show evidence for rest-frame emission-line equivalent widths EWrest > 240 (A) over circle that might imply a nonstandard initial mass function. One candidate is detected by Chandra, implying an AGN fraction of 2% +/- 2% for LAE candidate samples. In summary, LAEs at z similar to 3 have rapid star formation, low stellar mass, little dust obscuration, and no evidence for a substantial AGN component.
引用
收藏
页码:L13 / L16
页数:4
相关论文
共 49 条
[1]   ESO imaging survey -: Deep public survey:: Multi-color optical data for the Chandra Deep Field South [J].
Arnouts, S ;
Vandame, B ;
Benoist, C ;
Groenewegen, MAT ;
da Costa, L ;
Schirmer, M ;
Mignani, RP ;
Slijkhuis, R ;
Hatziminaoglou, E ;
Hook, R ;
Madejsky, R ;
Rité, C ;
Wicenec, A .
ASTRONOMY & ASTROPHYSICS, 2001, 379 (02) :740-754
[2]   First-year Wilkinson Microwave Anisotropy Probe (WMAP) observations:: Preliminary maps and basic results [J].
Bennett, CL ;
Halpern, M ;
Hinshaw, G ;
Jarosik, N ;
Kogut, A ;
Limon, M ;
Meyer, SS ;
Page, L ;
Spergel, DN ;
Tucker, GS ;
Wollack, E ;
Wright, EL ;
Barnes, C ;
Greason, MR ;
Hill, RS ;
Komatsu, E ;
Nolta, MR ;
Odegard, N ;
Peiris, HV ;
Verde, L ;
Weiland, JL .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2003, 148 (01) :1-27
[3]   Stellar population synthesis at the resolution of 2003 [J].
Bruzual, G ;
Charlot, S .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 344 (04) :1000-1028
[4]   ON NEAR-INFRARED H-ALPHA SEARCHES FOR HIGH-REDSHIFT GALAXIES [J].
BUNKER, AJ ;
WARREN, SJ ;
HEWETT, PC ;
CLEMENTS, DL .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1995, 273 (02) :513-&
[5]   Dust and recent star formation in the core of NGC 5253 [J].
Calzetti, D ;
Meurer, GR ;
Bohlin, RC ;
Garnett, DR ;
Kinney, AL ;
Leitherer, C ;
StorchiBergmann, T .
ASTRONOMICAL JOURNAL, 1997, 114 (05) :1834-+
[6]   A measurement of the contamination in [O III] λ5007 surveys of intracluster stars and the surface density of z=3.13 Lyα galaxies [J].
Ciardullo, R ;
Feldmeier, JJ ;
Krelove, K ;
Jacoby, GH ;
Gronwall, C .
ASTROPHYSICAL JOURNAL, 2002, 566 (02) :784-793
[7]   High-z Lyα emitters.: I.: A blank-field search for objects near redshift z=3.4 in and around the Hubble deep field and the Hawaii Deep Field SSA 22 [J].
Cowie, LL ;
Hu, EM .
ASTRONOMICAL JOURNAL, 1998, 115 (04) :1319-1328
[8]   Spectroscopic properties of the z≈4.5 Lyα emitters [J].
Dawson, S ;
Rhoads, JE ;
Malhotra, S ;
Stern, D ;
Dey, A ;
Spinrad, H ;
Jannuzi, BT ;
Wang, JX ;
Landes, E .
ASTROPHYSICAL JOURNAL, 2004, 617 (02) :707-717
[9]   GaBoDS: The Garching-Bonn Deep Survey - IV. Methods for the image reduction of multi-chip cameras demonstrated on data from the ESO wide-field imager [J].
Erben, T ;
Schirmer, M ;
Dietrich, JP ;
Cordes, O ;
Haberzettl, L ;
Hetterscheidt, M ;
Hildebrandt, H ;
Schmithuesen, O ;
Schneider, P ;
Simon, P ;
Deul, E ;
Hooks, RN ;
Kaiser, N ;
Radovich, M ;
Benoist, C ;
Nonino, M ;
Olsen, LF ;
Prandoni, I ;
Wichmann, R ;
Zaggia, S ;
Bomans, D ;
Dettmar, RJ ;
Miralles, JM .
ASTRONOMISCHE NACHRICHTEN, 2005, 326 (06) :432-464
[10]   A search for Lyα emitters at redshift 3.7 [J].
Fujita, SS ;
Ajiki, M ;
Shioya, Y ;
Nagao, T ;
Murayama, T ;
Taniguchi, Y ;
Okamura, S ;
Ouchi, M ;
Shimasaku, K ;
Doi, M ;
Furusawa, H ;
Hamabe, M ;
Kimura, M ;
Komiyama, Y ;
Miyazaki, M ;
Miyazaki, S ;
Nakata, F ;
Sekiguchi, M ;
Yagi, M ;
Yasuda, N ;
Matsuda, Y ;
Tamura, H ;
Hayashino, T ;
Kodaira, K ;
Karoji, H ;
Yamada, T ;
Ohta, K ;
Umemura, M .
ASTRONOMICAL JOURNAL, 2003, 125 (01) :13-31