J/MNRAS/499/3610 Lyman-α emitters lensed by galaxies (Cao+, 2020)
LESSER: a catalogue of spectroscopically selected sample of Lyman-α
emitters lensed by galaxies.
Cao X., Li R., Shu Y., Mao S., Kneib J.-P., Gao L.
<Mon. Not. R. Astron. Soc., 499, 3610-3619 (2020)>
=2020MNRAS.499.3610C 2020MNRAS.499.3610C (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing ; Galaxies ; Redshifts ;
Velocity dispersion ; Spectra, optical
Keywords: gravitational lensing: strong - techniques: spectroscopic -
galaxies: elliptical and lenticular, cD - dark matter
Abstract:
We introduce the LEnSed laeS in the Eboss suRvey (LESSER) project,
which aims to search for lensed Lyman-α emitters (LAEs) in the
Extended Baryon Oscillation Spectroscopic Survey (eBOSS). The final
catalogue contains 361 candidate lensing systems. The lens galaxies
are luminous red galaxies (LRGs) at redshift 0.4<z<0.8, and the source
galaxies are LAEs at redshift 2<z<3. The spectral resolution of eBOSS
(∼2000) allows us to further identify the fine structures of
Lyman-α (Lyα) emissions. Among our lensed LAE candidates,
281 systems present single-peaked line profiles while 80 systems show
double-peaked features. Future spectroscopic/imaging follow-up
observations of the catalogue may shed light on the origin of diverse
Lyα line morphology, and provide promising labs for studying
low-mass dark matter haloes/subhaloes.
Description:
The spectroscopic method of identifying lens systems has been well
described in previous works (Bolton et al. 2004AJ....127.1860B 2004AJ....127.1860B;
Brownstein et al. 2012ApJ...744...41B 2012ApJ...744...41B). Shu et al.
(2016ApJ...824...86S 2016ApJ...824...86S, Cat. J/ApJ/824/86) extended this method to
search for lensed LAEs. In this paper, we apply the same technique as
that used in Shu et al. (2016ApJ...824...86S 2016ApJ...824...86S, Cat. J/ApJ/824/86) to
the eBOSS data (Ahumada et al. 2020ApJS..249....3A 2020ApJS..249....3A, Cat. V/154), with
modifications to distinguish between single- and double-peaked
Lyα emission lines.
In total, we find 361 lensed LAE candidates from the eBOSS data base,
281 candidates of which are single-peaked, and 80 candidates are
double-peaked. The detailed information of our candidates is listed in
Tables 1 and 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 90 281 Catalogue of single-peaked candidates
table2.dat 90 80 Catalogue of double-peaked candidates
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See also:
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16)
(Ahumada+, 2020)
J/ApJ/824/86 : The BOSS emission-line lens survey. III. (Shu+, 2016)
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name SDSS plate-fibre-mjd
17- 18 I2 h RAh Right ascension (J2000)
20- 21 I2 min RAm Right ascension (J2000)
23- 27 F5.2 s RAs Right ascension (J2000)
29 A1 --- DE- Declination sign (J2000)
30- 31 I2 deg DEd Declination (J2000)
33- 34 I2 arcmin DEm Declination (J2000)
36- 40 F5.2 arcsec DEs Declination (J2000)
42- 45 F4.2 --- zl Redshift of lens galaxy
47- 50 F4.2 --- zs Redshift of background lensed
Lyman-α emitter
52- 56 F5.2 mag imag i-band SDSS cmodel magnitude of lens
galaxy
58- 63 F6.2 10-20W/m2 FLya Line flux of Lyα emission
quantified by the skew-normal fit
65- 68 F4.2 0.1nm Width Width of Lyα emission quantified by
the skew-normal fit (1)
70- 73 F4.2 --- Skewness Skewness of Lyα emission quantified
by the skew-normal fit (1)
75- 80 F6.2 km/s sigma Velocity dispersion of lens galaxy
82- 86 F5.2 arcsec thetaE Predicted Einstein radius of lens galaxy
88 A1 --- Grade Grade of the candidate based on colour
images from the DECaLs survey (2)
90 A1 --- f_Grade [*] Flag on Grade (3)
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Note (1): For double-peaked candidates, width and skewness are the
characteristics of the red peak
Note (2): We check whether our candidates already exhibit some lensed features
in the images from the DESI Legacy Imaging Surveys (Dey et al.
2019AJ....157..168D 2019AJ....157..168D) and classify our candidates into grades
by visual inspection. Grade as follows:
A = multiple images or an arc with a counter-image surrounding the main
lens is observed. The lensed feature and main lens have different
colours. The Einstein radius inferred from the image is smaller than
5arcsec.
B = a secondary image or an arc of a different colour from the lens object
is observed, but no obvious counter-image can be observed.
C = no discernable lensing feature exists.
Note (3): Flag as follows:
* = Candidate already found by the BELLS GALLERY project
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 06-Sep-2023