J/A+A/498/13 Lyman-α emitters from redshifts z∼2-3 (Nilsson+, 2009)
Evolution in the properties of Lyman-α emitters from redshifts z∼3 to z∼2.
Nilsson K.K., Tapken C., Moller P., Freudling W., Fynbo J.P.U.,
Meisenheimer K., Laursen P., Oestlin G.
<Astron. Astrophys., 498, 13-23 (2009)>
=2009A&A...498...13N 2009A&A...498...13N
ADC_Keywords: Surveys ; Photometry ; Redshifts ; Equivalent widths ; Ultraviolet
Keywords: cosmology: observations - galaxies: high redshift
Abstract:
Narrow-band surveys to detect Lyα emitters are powerful tools
for identifying high, and very high, redshift galaxies. Although
samples are increasing at redshifts z=3-6, the nature of these
galaxies is still poorly known. The number of galaxies detected at
redshifts below z∼3 are also small.
We study the properties of z=2.25 Lyα emitters and compare them
with those of z>3 Lyα emitters
We present narrow-band imaging made with the MPG/ESO 2.2m telescope
and the WFI (Wide Field Imager) detector. Using this data, we have
searched for emission-line objects. We find 170 candidate typical
Lyα emitters and 17 candidates that we regard as high
UV-transmission Lyα emitters. We have derived the magnitudes
of these objects in 8 photometric bands from u* to Ks, and
studied whether they have X-ray and/or radio counterparts.
Description:
In March 2007, a 35x34arcmin2 section of the COSMOS field, centred
on 10:00:27+02:12:22.7 (J2000), was observed with the Wide-Field
Imager (WFI) on the MPG/ESO 2.2m telescope on La Silla. The 386
candidates were split into the different categories of [Likely,
Unlikely, Rejected] = [187, 61, 138]. In Table 2, we list the
coordinates, EWs, significance of the EWs, continuum-subtracted
narrow-band magnitudes mag3960 and mean UV spectral index beta of all
likely candidates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 58 187 Coordinates, observed equivalent widths, continuum
subtracted narrow-band magnitudes and UV spectral
index β of the likely candidates
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See also:
J/PASJ/57/165 : Lyα emitters in the SUBARU Deep Field (Taniguchi+, 2005)
J/PASJ/57/881 : Imaging of high-redshift Lyman alpha emitters (Yamada+, 2005)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [NTM2009] LAE-COSMOS sequential number,
[NTM2009] LAE-COSMOS NNN in Simbad
5- 13 F9.5 deg RAdeg Right ascension in decimal degrees (J2000)
15- 21 F7.5 deg DEdeg Declination in decimal degrees (J2000)
23- 28 F6.1 0.1nm EW Lymanα equivalent width
30- 34 F5.1 0.1nm e_EW rms uncertainty on EW
36- 40 F5.2 mag m3960 Continuum subtracted narrow-band magnitude at
396nm
42- 45 F4.2 mag e_m3960 rms uncertainty on m3960
47- 51 F5.2 --- beta ?=- UV spectral index β (1)
53- 56 F4.2 --- e_beta ?=- rms uncertainty on beta
58 A1 --- Note [G] G for candidates detected with GALEX
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Note (1): the UV spectral index β is defined such that
F(λ) ∝ λβ
(see section 4.1 of the paper)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 18-Jan-2010