J/ApJS/254/26 Identifying 3FHL. V. CTIO-COSMOS spectra (Rajagopal+, 2021)
Identifying the 3FHL catalog.
V. Results of the CTIO-COSMOS optical spectroscopy campaign 2019.
Rajagopal M., Marchesi S., Kaur A., Dominguez A., Silver R., Ajello M.
<Astrophys. J. Suppl. Ser., 254, 26 (2021)>
=2021ApJS..254...26R 2021ApJS..254...26R
ADC_Keywords: Active gal. nuclei; Spectra, optical; Gamma rays;
Cross identifications
Keywords: Active galactic nuclei ; Blazars ; Active galaxies ; Galaxy nuclei ;
Spectroscopy ; Interstellar emissions ; Optical observatories ;
Optical observation
Abstract:
As a follow-up to the optical spectroscopic campaign aimed at
achieving completeness in the Third Catalog of Hard Fermi-LAT Sources
(3FHL), we present here the results of a sample of 28 blazars of an
uncertain type observed using the 4m telescope at Cerro Tololo
Inter-American Observatory in Chile. Out of these 28 sources, we find
that 25 are BL Lacertae objects (BL Lacs) and 3 are flat-spectrum
radio quasars (FSRQs). We measure redshifts or lower limits for 16 of
these blazars, and it is observed that the 12 remaining blazars have
featureless optical spectra. These results are part of a more extended
optical spectroscopy follow-up campaign for 3FHL blazars, where, until
now, 51 blazars of an uncertain type have been classified into BL Lac
and FSRQ categories. Furthermore, this campaign has resulted in
redshift measurements and lower limits for 15 of these sources. Our
results contribute toward attaining a complete sample of blazars above
10 GeV, which then will be crucial in extending our knowledge on
blazar emission mechanisms and the extragalactic background light.
Description:
All the source spectra for this work were obtained using the Cerro
Tololo Ohio State Multi-Object Spectrograph (COSMOS) mounted on the 4m
Blanco telescope located at the Cerro Tololo Inter-American
Observatory (CTIO) facility in Chile (λ=5000-9000Å, R∼2100).
The observations were performed over three nights in 2019 April and
over four nights in 2019 June.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 109 28 List of sources and their properties sorted
in the order of increasing R.A. values
sp/* . 28 Individual spectrum file in FITS format
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See also:
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
J/A+A/495/691 : Multifrequency catalog of blazars, Roma-BZCAT (Massaro+, 2009)
J/A+A/538/A26 : BL Lac objects beyond z=1.3 (Rau+, 2012)
J/ApJ/748/49 : Optical spectroscopy of 1LAC broad-line blazars (Shaw+, 2012)
J/ApJ/764/135 : Spectroscopic redshifts of BL Lac objects (Shaw+, 2013)
J/ApJ/780/73 : Redshifts of BL Lac objects from Fermi (Ajello+, 2014)
J/A+A/579/A34 : 1WHSP: VHE γ-ray blazar candidates (Arsioli+, 2015)
J/ApJS/232/18 : The third Fermi-LAT >10GeV catalog (3FHL) (Ajello+, 2017)
J/A+A/598/A17 : The 2WHSP catalog (Chang+, 2017)
J/ApJS/233/3 : VLBA Extragalactic Proper Motion Catalog (Truebenbach+, 2017)
J/ApJS/247/33 : The Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)
J/A+A/643/A103 : Fermi-LAT sources low-energy counterparts (Pena-Herazo+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- 3FHL 3FHL source name (JHHMM.m+DDMM)
14- 34 A21 --- CName Optical, IR, X-ray or radio counterpart name
36- 37 I2 h RAh Hour of right ascension (J2000)
39- 40 I2 min RAm Minute of right ascension (J2000)
42- 46 F5.2 s RAs Second of right ascension (J2000)
48 A1 --- DE- Sign of declination (J2000)
49- 50 I2 deg DEd Degree of declination (J2000)
52- 53 I2 arcmin DEm Arcminute of declination (J2000)
55- 59 F5.2 arcsec DEs Arcsecond of declination (J2000)
61- 66 F6.4 mag E(B-V) [0.01/0.78] Reddening (1)
68- 72 F5.2 mag Vmag [15.38/20.21] V-band magnitude (AB system)
74- 84 A11 "Y:M:D" Date Date of observation (UT)
86- 89 I4 s Exp [900/6200] Exposure time of the source
under consideration
91- 95 F5.2 --- Slope [-4.92/1.6] Slope of the continuum fit
obtained from the observed spectra
97-109 A13 --- FileName Name of the file in subdirectory "sp/";
column added by CDS
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Note (1): E(B-V) value obtained using the measurements of
Schlafly & Finkbeiner (2011ApJ...737..103S 2011ApJ...737..103S) and the NASA/IPAC Infrared
Science Archive online tool.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 18-Aug-2021