J/ApJ/902/86 Type Ic SN 2020bvc UV to NIR LCs and opt. spectra (Ho+, 2020)
SN 2020bvc: a broad-line type Ic supernova with a double-peaked optical light
curve and a luminous X-ray and radio counterpart.
Ho A.Y.Q., Kulkarni S.R., Perley D.A., Cenko S.B., Corsi A., Schulze S.,
Lunnan R., Sollerman J., Gal-Yam A., Anand S., Barbarino C., Bellm E.C.,
Bruch R.J., Burns E., De K., Dekany R., Delacroix A., Duev D.A.,
Frederiks D.D., Fremling C., Goldstein D.A., Golkhou V.Z., Graham M.J.,
Hale D., Kasliwal M.M., Kupfer T., Laher R.R., Martikainen J., Masci F.J.,
Neill J.D., Ridnaia A., Rusholme B., Savchenko V., Shupe D.L.,
Soumagnac M.T., Strotjohann N.L., Svinkin D.S., Taggart K., Tartaglia L.,
Yan L., Zolkower J.
<Astrophys. J., 902, 86 (2020)>
=2020ApJ...902...86H 2020ApJ...902...86H
ADC_Keywords: Supernovae; Photometry, ugriz; Photometry, ultraviolet
Keywords: Radio transient sources ; High energy astrophysics ;
Transient sources ; Core-collapse supernovae ; Supernovae ;
Type Ic supernovae ; X-ray transient sources ; Gamma-ray bursts
Abstract:
We present optical, radio, and X-ray observations of SN 2020bvc
(=ASASSN-20bs, ZTF 20aalxlis), a nearby (z=0.0252; d = 114Mpc)
broad-line (BL) Type Ic supernova (SN) and the first double-peaked
Ic-BL discovered without a gamma-ray burst (GRB) trigger. Our
observations show that SN 2020bvc shares several properties in common
with the Ic-BL SN 2006aj, which was associated with the low-luminosity
gamma-ray burst (LLGRB) 060218. First, the 10GHz radio luminosity
(Lradio∼1037erg/s) is brighter than ordinary core-collapse SNe but
fainter than LLGRB SNe such as SN 1998bw (associated with
LLGRB980425). We model our VLA observations (spanning 13-43days) as
synchrotron emission from a mildly relativistic (v≳0.3c) forward
shock. Second, with Swift and Chandra, we detect X-ray emission
(LX∼1041erg/) that is not naturally explained as inverse Compton
emission or part of the same synchrotron spectrum as the radio
emission. Third, high-cadence (6x night-1) data from the Zwicky
Transient Facility (ZTF) show a double-peaked optical light curve, the
first peak from shock cooling of extended low-mass material (mass
Me<10-2M☉ at radius Re>1012cm) and the second peak from
the radioactive decay of 56Ni. SN 2020bvc is the first double-peaked
Ic-BL SN discovered without a GRB trigger, so it is noteworthy that it
shows X-ray and radio emission similar to LLGRB SNe. For four of the
five other nearby (z≲0.05) Ic-BL SNe with ZTF high-cadence data, we
rule out a first peak like that seen in SN 2006aj and SN 2020bvc,
i.e., that lasts ∼1day and reaches a peak luminosity M~-18. Follow-up
X-ray and radio observations of Ic-BL SNe with well-sampled early
optical light curves will establish whether double-peaked optical
light curves are indeed predictive of LLGRB-like X-ray and radio
emission.
Description:
On 2020 February 4.34, SN2020bvc was detected at i=17.48±0.05mag at
RAJ2000=14:33:57.01,DEJ2000=+40:14:37.5 as part of the Zwicky
Transient Facility (ZTF) Uniform Depth Survey (ZUDS;
D. A. Goldstein et al. 2020, in preparation) with the 48 inch Samuel
Oschin Schmidt telescope at Palomar Observatory (P48).
SN 2020bvc was observed almost nightly in gri by the P48 for the first
month postexplosion. We obtained additional ugriz and gri photometry
using the IO:O on the Liverpool Telescope (LT) and the Spectral Energy
Distribution Machine (SEDM) on the P60, respectively.
We obtained 10 observations of SN 2020bvc with the Ultraviolet/Optical
Telescope (UVOT) and X-Ray Telescope (XRT) on board the Neil Gehrels
Swift Observatory under a target-of-opportunity program (PI: Schulze).
The first observation was on February 5.02 (Δt=1.35). We also
obtained two 10ks observations with the Chandra X-ray Observatory
under Director's Discretionary Time (PI: A. Ho), one epoch on February
16 (Δt=13.2) and one epoch on February 29 (Δt=25.4).
Two hours after the first detection, we obtained a spectrum using
SEDM, a low-resolution spectrograph on the P60. On February 8.24,
we obtained a spectrum using the Spectrograph for the Rapid Acquisition
of Transients (SPRAT) on the LT.
We obtained 13 ground-based optical spectra using the SEDM, the
Andalusia Faint Object Spectrograph and Camera (ALFOSC) on the Nordic
Optical Telescope (NOT), the Double Beam Spectrograph (DBSP) on the
200 inch Hale telescope at Palomar Observatory, SPRAT on the LT, and
the Low Resolution Imaging Spectrometer (LRIS) on the Keck I 10m
telescope.
See Section for further observation explanations.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
14 33 57.01 +40 14 37.6 SN2020bvc = ZTF20aalxlis
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 43 220 UV-to-IR photometry for SN2020bvc, corrected for
Milky Way extinction
fig4.dat 29 15262 Optical spectra of SN2020bvc
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See also:
J/MNRAS/383/1485 : BVRI light curves of SN 2003jd (Valenti+, 2008)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
J/ApJ/702/226 : Swift/UVOT panchromatic obs. of SN 2008D (Modjaz+, 2009)
J/other/Nat/463.513 : Radio observations of SN 2009bb (Soderberg+, 2010)
J/ApJ/742/L18 : Follow-up photometry of SNIIb PTF11eon (Arcavi+, 2011)
J/AJ/141/163 : Ultimate LC of SN 1998bw/GRB 980425 (Clocchiatti+, 2011)
J/MNRAS/412/1441 : SNe luminosity functions (Li+, 2011)
J/ApJ/759/107 : Core-collapse SNe and host galaxies (Kelly+, 2012)
J/ApJS/213/19 : Optical & near-IR light curves of 64 SNe (Bianco+, 2014)
J/ApJ/781/37 : Multi-band photometry of GRB 130427A (Perley+, 2014)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/ApJS/211/13 : The second Fermi/GBM GRB cat. (4yr) (von Kienlin+, 2014)
J/ApJS/219/8 : SFR for WISE + SDSS spectroscopic galaxies (Chang+, 2015)
J/A+A/593/A68 : PTF12os & iPTF13bvn spectra & LCs (Fremling+, 2016)
J/A+A/594/A116 : HI4PI spectra and column density maps (HI4PI team+, 2016)
J/ApJ/832/108 : Spectral data of Type Ic & Ic-bl SNe (Modjaz+, 2016)
J/ApJ/851/107 : iPTF 16asu photometry follow-up (Whitesides+, 2017)
J/other/Sci/362.201 : iPTF 14gqr (SN 2014ft) photometry (De+, 2018)
J/ApJ/887/169 : UV-Opt light curves of the type Ic SN 2018gep (Ho+, 2019)
J/ApJ/886/152 : ZTF early obs. of Type Ia SNe. I. LCs (Yao+, 2019)
J/ApJ/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 2020)
J/ApJ/893/132 : Optical follow-up of SNIc ZTF18aaqjovh (Ho+, 2020)
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d MJD [58883.3/58912.6] Modified Julian Date
12- 16 F5.2 d DeltaT [0.67/29.88] Time since t0; 2020 Feb 03.67 UTC
18- 27 A10 --- Inst Instrument used (1)
29- 32 A4 --- Filt Filter used
34- 38 F5.2 mag mag [16.26/22.23] Apparent AB magnitude in Filt
40- 43 F4.2 mag e_mag [0.01/0.1] Uncertainty in mag
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Note (1): Instrument as follows:
P48+ZTF = the 48 inch Samuel Oschin Schmidt telescope at
Palomar Observatory (134 occurrences)
Swift+UVOT = Ultraviolet/Optical telescope on board the Neil Gehrels
Swift Observatory (61 occurrences)
LT+IOO = the IO:O on the Liverpool Telescope (15 occurrences)
P60+SEDM = the Spectral Energy Distribution Machine on the automated
60 inch telescope at Palomar Observatory (10 occurrences)
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Byte-by-byte Description of file: fig4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 F5.2 d t0 [0.76/47.9] Time since reference epoch:
2020 Feb 03.67 UTC
7- 15 F9.3 0.1nm lambda [3061.6/10305] Wavelength in Angstroms
17- 29 E13.6 cW/m2/nm Flux [-0.44/2.04]? Flux density
in erg/s/cm2/Å (1)
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Note (1): Except for the LT/SPRAT data (t0=4.6 and 42.6) which are
normalized fluxes.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 14-Apr-2022