J/ApJ/895/L23 Radio observation of the transient CSS161010 (Coppejans+, 2020)
A Mildly Relativistic Outflow from the Energetic, Fast-rising Blue Optical
Transient CSS161010 in a Dwarf Galaxy.
Coppejans D.L., Margutti R., Terreran G., Nayana A.J., Coughlin E.R.,
Laskar T., Alexander K.D., Bietenholz M., Caprioli D., Chandra P.,
Drout M.R., Frederiks D., Frohmaier C., Hurley K.H., Kochanek C.S.,
MacLeod M., Meisner A., Nugent P.E., Ridnaia A., Sand D.J., Svinkin D.,
Ward C., Yang S., Baldeschi A., Chilingarian I.V., Dong Y., Esquivia C.,
Fong W., Guidorzi C., Lundqvist P., Milisavljevic D., Paterson K.,
Reichart D.E., Shappee B., Stroh M.C., Valenti S., Zauderer B.A., Zhang B.
<Astrophys. J., 895, L23 (2020)>
=2020ApJ...895L..23C 2020ApJ...895L..23C
ADC_Keywords: Radio sources; Spectra, radio
Keywords: Supernovae ; Accretion ; Black holes ; X-ray transient sources ;
Radio transient sources
Abstract:
We present X-ray and radio observations of the Fast Blue Optical
Transient CRTS-CSS161010J045834-081803 (CSS161010 hereafter) at
t=69-531days. CSS161010 shows luminous X-ray (Lx∼5x1039erg/s) and
radio (Lν∼1029erg/s/Hz) emission. The radio emission peaked at
∼100days post-transient explosion and rapidly decayed. We interpret
these observations in the context of synchrotron emission from an
expanding blast wave. CSS161010 launched a mildly relativistic outflow
with velocity Γβc≳0.55c at ∼100days. This is faster than
the non- relativistic AT 2018cow (Γβc∼0.1c) and closer to
ZTF18abvkwla (Γβc≳0.3c at 63days). The inferred initial
kinetic energy of CSS161010 (Ek≳1051erg) is comparable to that of
long gamma-ray bursts, but the ejecta mass that is coupled to the
mildly relativistic outflow is significantly larger
(∼0.01-0.1M☉). This is consistent with the lack of observed
γ-rays. The luminous X-rays were produced by a different
emission component to the synchrotron radio emission. CSS161010 is
located at ∼150Mpc in a dwarf galaxy with stellar mass M*∼107M☉
and specific star formation rate sSFR∼0.3/Gyr. This mass is among the
lowest inferred for host galaxies of explosive transients from massive
stars. Our observations of CSS161010 are consistent with an
engine-driven aspherical explosion from a rare evolutionary path of a
H-rich stellar progenitor, but we cannot rule out a stellar tidal
disruption event on a centrally located intermediate-mass black hole.
Regardless of the physical mechanism, CSS161010 establishes the
existence of a new class of rare (rate<0.4% of the local core-collapse
supernova rate) H-rich transients that can launch mildly relativistic
outflows.
Description:
We observed CSS161010 with the NSF's Karl G. Jansky Very Large Array
(VLA) through project VLA/16B-425 and VLA/18A-123 (PI: Coppejans) over
five epochs from 2016 December to 2018 March, δt=69-530days
after explosion.
We observed CSS161010 for 10hours with the Giant Metrewave Radio
Telescope (GMRT) under the project code DDTB287 (PI: Coppejans). These
observations were carried out on 2017 September 14.93, 21.96, 19.88 UT
(δt=344-351days after explosion) at frequencies 1390, 610, and
325MHz, respectively.
Objects:
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RA (2000) DE Designation(s)
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04 58 34.0 -08 18 03 CSS161010 = CRTS CSS161010 J045834-081803
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 44 118 Radio observations of CSS161010
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See also:
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/A+A/479/49 : Supernova rates from STRESS (Botticella+, 2008)
J/ApJ/696/870 : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)
J/other/Nat/463.513 : Radio observations of SN 2009bb (Soderberg+, 2010)
J/ApJ/746/156 : Radio afterglow observations of GRBs (Chandra+, 2012)
J/MNRAS/428/729 : GRB Swift X-ray light curves analysis (Margutti+, 2013)
J/ApJ/794/23 : Pan-STARRS1 transients optical photometry (Drout+, 2014)
J/ApJ/813/82 : z<0.06 broad-line AGN emission-line measures (Reines+, 2015)
J/ApJ/819/35 : Light curves of 4 transients from PTF & SNLS (Arcavi+, 2016)
J/MNRAS/455/2918 : Photometry & line luminosities ASASSN-14li (Holoien+, 2016)
J/ApJ/844/46 : Photometry of transient event iPTF16fnl (Blagorodnova+, 2017)
J/ApJ/836/25 : Swift UVOT light curves of ASASSN-15lh (Margutti+, 2017)
J/ApJ/851/107 : iPTF 16asu photometry follow-up (Whitesides+, 2017)
J/A+A/618/A104 : NGC3278, SN2009bb host, ATCA & MUSE data (Michalowski+,2018)
J/ApJ/853/62 : Optical and NIR spectra & LCs of SN2016ija (Tartaglia+, 2018)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Obs.Y [2016/2018] Start Date, YYYY
6- 7 I2 "month" Obs.M Start Date, Month
9- 10 I2 d Obs.D Start Date, Day in Month
12- 14 I3 d JD [69/531] Julian Date; JD-2457668
16- 20 F5.2 GHz Freq [0.33/25] Frequency
22- 26 F5.3 GHz Band [0.03/4.1] Bandwidth
28- 28 A1 --- l_Flux Limit flag for Flux
29- 33 F5.3 mJy Flux [0.01/7.1] Flux Density
35- 39 F5.3 mJy e_Flux [0.008/0.7]? Uncertainty in Flux
41- 44 A4 --- Tel Telescope (1)
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Note (1): Telescopes as follows:
GMRT = Giant Metrewave Radio Telescope (3 occurrences)
VLA = Very Large Array (115 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDs], 23-Sep-2021