J/ApJ/736/31 HETDEX pilot survey. II. 1.9<z<3.8 LAEs (Blanc+, 2011)
The HETDEX pilot survey.
II. The evolution of the Lyα escape fraction from the ultraviolet slope
and luminosity function of 1.9 < z < 3.8 LAEs.
Blanc G.A., Adams J.J., Gebhardt K., Hill G.J., Drory N., Hao L.,
Bender R., Ciardullo R., Finkelstein S.L., Fry A.B., Gawiser E.,
Gronwall C., Hopp U., Jeong D., Kelzenberg R., Komatsu E., MacQueen P.,
Murphy J.D., Roth M.M., Schneider D.P., Tufts J.
<Astrophys. J., 736, 31 (2011)>
=2011ApJ...736...31B 2011ApJ...736...31B
ADC_Keywords: Galaxies, spectra ; Redshifts ; Surveys ; Ultraviolet ;
Equivalent widths
Keywords: dust, extinction - evolution - galaxies: evolution -
galaxies: high-redshift - galaxies: ISM
Abstract:
We study the escape of Lyα photons from Lyα emitting
galaxies (LAEs) and the overall galaxy population using a sample of 99
LAEs at 1.9<z<3.8 detected through integral-field spectroscopy of
blank fields by The Hobby Eberly Telescope Dark Energy Experiment
Pilot Survey. For 89 LAEs with broadband counterparts we measure
ultraviolet (UV) luminosities and UV slopes, and estimate E(B-V) under
the assumption of a constant intrinsic UV slope for LAEs. These
quantities are used to estimate dust-corrected star formation rates
(SFRs). Comparison between the observed Lyα luminosity and that
predicted by the dust-corrected SFR yields the Lyα escape
fraction. We also measure the Lyα luminosity function and
luminosity density (ρLyα) at 2<z<4. Using this and other
measurements from the literature at 0.3<z<7.7 we trace the redshift
evolution of ρLyα. We compare it to the expectations from
the star formation history of the universe and characterize the
evolution of the Lyα escape fraction of galaxies.
Description:
The HETDEX Pilot Survey obtained integral-field spectroscopy over
∼169.23arcmin2 of blank sky in four extra-galactic fields (COSMOS:
71.6arcmin2, GOODS-N: 35.5arcmin2, MUNICS-S2: 49.9arcmin2, and
XMM-LSS: 12.3arcmin2) using VIRUS-P (Visible Integral-field
Replicable Unit Spectrograph Prototype) on the 2.7m Harlan J. Smith
telescope at McDonald Observatory, from 2007 September to 2010
February. The goal of the survey is to conduct an unbiased search for
spectroscopically detected emission line galaxies over a wide range of
redshifts. The observations and data reduction, as well as the
detection and classification of emission line galaxies, are presented
in Paper I (Adams et al. 2011, Cat. J/ApJS/192/5).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 77 99 Properties of HETDEX Pilot Survey LAEs
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See also:
J/ApJS/192/5 : Emission-line galaxies from HETDEX pilot survey (Adams+, 2011)
J/ApJ/736/18 : Lyman-continuum emission at z∼3 in SSA22 field (Nestor+, 2011)
J/ApJ/711/928 : Low-redshift Lyα galaxies from GALEX (Cowie+, 2010)
J/A+A/498/13 : Lyman-α emitters from redshifts z∼2-3 (Nilsson+, 2009)
J/ApJ/705/639 : Sizes of Lyman alpha emitters at z=3.1 (Bond+, 2009)
J/ApJ/614/75 : Lymanα emitting galaxies at z=2.38 (Francis+, 2004)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [HPS-]
5- 7 I3 --- HPS [3/474] Identification number (1)
9- 12 F4.2 --- z [2.08/3.74] Redshift
14- 18 F5.1 10+35W L(Lya) Lyα (1216Å) luminosity (1042erg/s)
20- 22 F3.1 10+35W e_L(Lya) L(Lya) uncertainty
24- 27 F4.1 10+21W/Hz Lnu [0.4/47.5]? UV luminosity at 1500Å
(Lν,1500Å in 1028erg/s/Hz) (2)
29- 31 F3.1 10+21W/Hz e_Lnu ? Lnu uncertainty
33- 36 F4.1 --- beta ? the UV continuum slope (β)
38- 40 F3.1 --- e_beta ? beta uncertainty
42- 45 F4.2 mag E(B-V) [0/0.82]? Dust reddening
47- 50 F4.2 mag e_E(B-V) ? E(B-V) uncertainty
52- 55 F4.2 --- f(Lya) ? the escape fraction of Lyα photons
(fesc(Lyα)=the Lyα derived SFR to
the extinction corrected UV SFR ratio)
57- 62 F6.2 --- E_f(Lya) ? Positive error on f(Lya)
64- 67 F4.2 --- e_f(Lya) ? Negative error on f(Lya)
69- 72 I4 0.1nm EW0 ? Lyα equivalent width in Å
74- 77 I4 0.1nm e_EW0 ? EW0 uncertainty
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Note (1): ID corresponds to that in Table 3 of Adams et al. (2011,
Cat. J/ApJS/192/5). Equatorial coordinates and line fluxes are
provided there.
Note (2): Blank values indicate objects with no broadband counterpart.
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History:
From electronic version of the journal
References:
Adams et al. Paper I. 2011ApJS..192....5A 2011ApJS..192....5A Cat. J/ApJS/192/5
Finkelstein et al. Paper III. 2011ApJ...729..140F 2011ApJ...729..140F
(End) Emmanuelle Perret [CDS] 10-Dec-2012