J/PASJ/70/28 Subaru HSC counterpart candidates of GW170817 (Tominaga+, 2018)
Subaru Hyper Suprime-Cam Survey for an optical counterpart of GW170817.
Tominaga N., Tanaka M., Morokuma T., Utsumi Y., Yamaguchi M.S., Yasuda N.,
Tanaka M., Yoshida M., Fujiyoshi T., Furusawa H., Kawabata K.S., Lee C.-H.,
Motohara K., Ohsawa R., Ohta K., Terai T., Abe F., Aoki W., Asakura Y.,
Barway S., Bond I.A., Fujisawa K., Honda S., Ioka K., Itoh Y., Kawai N.,
Kim J.H., Koshimoto N., Matsubayashi K., Miyazaki S., Saito T.,
Sekiguchi Y., Sumi T., Tristram P.J.
<Publ. Astron. Soc. Jap., 70, 28 (2018)>
=2018PASJ...70...28T 2018PASJ...70...28T (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational wave; Optical; Stars, neutron
Keywords: gravitational waves; nuclear reactions; nucleosynthesis; abundances;
stars: neutron; surveys; Astrophysics -
High Energy Astrophysical Phenomena
Abstract:
We perform a z-band survey for an optical counterpart of the binary
neutron star coalescence GW170817 with Subaru/Hyper Suprime-Cam. Our
untargeted transient search covers 23.6deg2 corresponding to the
56.6% credible region of GW170817 and reaches the 50% completeness
magnitude of 20.6mag on average. As a result, we find 60 candidate
extragalactic transients, including J-GEM17btc (also known as
SSS17a/DLT17ck). While J-GEM17btc is associated with NGC 4993, which
is firmly located inside the 3D skymap of GW170817, the other 59
candidates do not have distance information in the GLADE v2 catalog or
NASA/IPAC Extragalactic Database. Among 59 of the candidates, 58 are
located at the center of extended objects in the Pan-STARRS1 catalog,
while one candidate has an offset. We present location, z-band
apparent magnitude, and time variability of the candidates and
evaluate the probabilities that they are located within the 3D skymap
of GW170817. The probability for J-GEM17btc is 64%, which is much
higher than for the other 59 candidates (9.3x10-3-2.1x10-1%).
Furthermore, the possibility that at least one of the other 59
candidates is located within the 3D skymap is only 3.2%. Therefore, we
conclude that J-GEM17btc is the most likely and distinguished
candidate to be the optical counterpart of GW170817.
Description:
We started the Subaru Hyper Suprime-Cam (HSC) observation on 2017
August 18.23 (UTC), corresponding to 0.7d after the GW170817
detection, and also performed HSC observation on August 19, 25, and
27. All the observations were carried out in the z-band.
We also choose the pointings located in footprints of Pan-STARRS1
(PS1, Chambers+ 2016, II/349) and use the PS1 catalog and images for
astrometric calibration and image subtraction, respectively.
Objects:
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RA (ICRS) DE Designation(s)
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13 09 48.09 -23 22 53.3 GW170817 = GrW 170817
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 34 60 The 60 final candidate extragalactic transients
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See also:
VII/198 : Mark III Catalog of Galaxy Peculiar Velocities (Willick+ 1997)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
VII/275 : GLADE catalog (Dalya+, 2016)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers, 2016)
IX/55 : XMM-Newton Serendipitous Source Catalogue 3XMM-DR8 (XMM-SSC, 2018)
J/A+A/465/71 : 21cm observations of 452 galaxies (Theureau+, 2007)
J/MNRAS/444/527 : Tully-Fisher distances for Spitzer galaxies (Sorce+, 2014)
J/MNRAS/445/2677 : Peculiar velocities in 6dFGS (Springob+, 2014)
J/A+A/588/A103 : 2nd ROSAT all-sky survey (2RXS) catalog (Boller+, 2016)
J/ApJ/848/L16 : Counterpart of GW170817. I. DECam. (Soares-Santos+, 2017)
J/ApJ/848/L29 : Opt. follow-up of GW170817 counterpart (Diaz+, 2017)
J/ApJ/848/L33 : Opt. follow-up of GW events with LCO (Arcavi+, 2017)
J/ApJ/851/L21 : UV-NIR obs. compil. of GW170817 counterpart (Villar+, 2017)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Name of the candidate;
<[TTM2018] J-GEM17aaa> for Simbad
12- 13 I2 h RAh Hour of right ascension (J2000)
15- 16 I2 min RAm Minute of right ascension (J2000)
18- 22 F5.2 s RAs Second of right ascension (J2000)
24 A1 --- DE- Sign of declination (J2000)
25- 26 I2 deg DEd Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 34 F4.1 arcsec DEs Arcsecond of declination (J2000)
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 11-Feb-2020