J/ApJ/896/165 Optical light curves of SN 2016hnk (Jacobson-Galan+, 2020)
Ca hnk: the calcium-rich transient supernova 2016hnk from a helium shell
detonation of a sub-Chandrasekhar white dwarf.
Jacobson-Galan W.V., Polin A., Foley R.J., Dimitriadis G., Kilpatrick C.D.,
Margutti R., Coulter D.A., Jha S.W., Jones D.O., Kirshner R.P., Pan Y.-C.,
Piro A.L., Rest A., Rojas-Bravo C.
<Astrophys. J., 896, 165 (2020)>
=2020ApJ...896..165J 2020ApJ...896..165J
ADC_Keywords: Photometry; Optical; Supernovae
Keywords: Type Ia supernovae ; White dwarf stars ; Supernovae ;
Observational astronomy
Abstract:
We present observations and modeling of SN 2016hnk, a Ca-rich
supernova (SN) that is consistent with being the result of a He-shell
double-detonation explosion of a C/O white dwarf. We find that
SN2016hnk is intrinsically red relative to typical thermonuclear SNe
and has a relatively low peak luminosity (MB=-15.4mag), setting it
apart from low-luminosity SNe Ia. SN 2016hnk has a fast-rising light
curve that is consistent with other Ca-rich transients (tr=15days).
We determine that SN 2016hnk produced 0.03±0.01M☉ of 56Ni
and 0.9±0.3M☉ of ejecta. The photospheric spectra show strong,
high-velocity CaII absorption and significant line blanketing at
λ<5000Å, making it distinct from typical (SN 2005E-like)
Ca-rich SNe. SN 2016hnk is remarkably similar to SN 2018byg, which was
modeled as a He-shell double-detonation explosion. We demonstrate that
the spectra and light curves of SN 2016hnk are well modeled by the
detonation of a 0.02M☉ helium shell on the surface of a
0.85M☉ C/O white dwarf. This analysis highlights the second
observed case of a He-shell double-detonation and suggests a specific
thermonuclear explosion that is physically distinct from SNe that are
defined simply by their low luminosities and strong [CaII] emission.
Description:
SN 2016hnk was discovered by the Asteroid Terrestrial-impact Last
Alert System (ATLAS) on 2016 October 27 (MJD 57688) using the ACAM1
instrument with a cyan filter.
We imaged SN 2016hnk between 2016 November 1 and 2017 February 17 with
the Direct camera on the Swope 1m telescope at Las Campanas
Observatory, Chile. Observations were performed in Johnson BV and
Sloan ugri filters.
Additional imaging of SN 2016hnk was obtained by the Las Cumbres
Observatory Global Telescope (LCOGT) and the Foundation Supernova
Survey with Pan-STARRS.
Final photometric observations of SN 2016hnk were obtained using the
imaging camera on the Keck telescope Low-resolution Imaging
Spectrometer (LRIS). The source was observed on 2017 July 20 in BR as
well as on 2017 August 16 in BVRI.
Objects:
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RA (ICRS) DE Designation(s)
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02 13 16.63 -07 39 40.8 SN 2016hnk = NAME ATLAS 16dpc
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 42 267 Optical photometry of SN 2016hnk
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See also:
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/PASP/117/773 : Classif. of SN host galaxies. III (van den Bergh+, 2005)
J/AJ/137/3731 : ESSENCE high-redshift supernova (Foley+, 2009)
J/MNRAS/417/2230 : BVRI+SDSS+2MASS and WISE phot. of 289 stars (Bilir+, 2011)
J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)
J/A+A/573/A2 : SN 2012Z spectra (Stritzinger+, 2015)
J/ApJ/836/60 : Bgri light curves of PTF11kmb and PTF12bho (Lunnan+, 2017)
J/ApJ/841/48 : UBVR and IR photometry of SN 2011fe (Ia) (Shappee+, 2017)
J/MNRAS/475/193 : Foundation SN Survey first data release (Foley+, 2018)
J/A+A/630/A76 : SN2016hnk photometry and spectroscopy (Galbany+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.2 d MJD [57659.57/57981.54] Modified Julian Date
of the observation
10- 16 F7.2 d Phase [-30.63/291.34] Time since B band maximum;
MJD 57690.18
18- 23 A6 --- Filt Filter used (ugriz, BVRI, "cyan" or "orange")
25- 25 A1 --- l_mag Limit flag on mag
27- 31 F5.2 mag mag [17.23/23.57] Apparent magnitude in Filter
33- 36 F4.2 mag e_mag [0.01/0.41]? Uncertanty in mag
38- 42 A5 --- Inst Instrument used (1)
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Note (1): Instrument as follows:
LCOGT = the Las Cumbres Observatory Global Telescope (159 occurrences)
Swope = the Direct camera on the Swope 1m telescope at Las Campanas
Observatory, Chile (65 occurrences)
PS1 = the Foundation Supernova Survey with Pan-STARRS
(see Foley+ 2018, J/MNRAS/475/193 ; 22 occurrences)
ATLAS = the Asteroid Terrestrial-impact Last Alert System using the ACAM1
instrument (15 occurrences)
Keck = the imaging camera on the Keck telescope Low-resolution Imaging
Spectrometer (LRIS; 6 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Nov-2021