J/ApJ/946/30 Type Ibn SN 2019kbj optical LCs and spectra (Ben-Ami+, 2023)
The type Ibn supernova 2019kbj: indications for diversity in type Ibn supernova
progenitors.
Ben-Ami T., Arcavi I., Newsome M., Farah J., Pellegrino C., Terreran G.,
Burke J., Hosseinzadeh G., McCully C., Hiramatsu D., Gonzalez E.P.,
Howell D.A.
<Astrophys. J., 946, 30 (2023)>
=2023ApJ...946...30B 2023ApJ...946...30B
ADC_Keywords: Supernovae; Photometry; Spectra, optical
Keywords: Supernovae ; Core-collapse supernovae ; Massive stars
Abstract:
Type Ibn supernovae (SNe) are a rare class of stellar explosions whose
progenitor systems are not yet well determined. We present and analyze
observations of the Type Ibn SN 2019kbj, and model its light curve in
order to constrain its progenitor and explosion parameters. SN 2019kbj
shows roughly constant temperature during the first month after peak,
indicating a power source (likely circumstellar material interaction)
that keeps the continuum emission hot at ∼15000K. Indeed, we find that
the radioactive decay of 56Ni is disfavored as the sole power source
of the bolometric light curve. A radioactive decay + circumstellar
material (CSM) interaction model, on the other hand, does reproduce
the bolometric emission well. The fits prefer a uniform-density CSM
shell rather than CSM due to a steady mass-loss wind, similar to what
is seen in other Type Ibn SNe. The uniform-density CSM shell model
requires ∼0.1M☉ of 56Ni and ∼1M☉ total ejecta mass to
reproduce the light curve. SN 2019kbj differs in this manner from
another Type Ibn SN with derived physical parameters, SN 2019uo, for
which an order of magnitude lower 56Ni mass and larger ejecta mass
were derived. This points toward a possible diversity in SN Ibn
progenitor systems and explosions.
Description:
We obtained BVgri-band imaging of SN 2019kbj with the Las Cumbres
Observatory (LCO) Sinistro cameras mounted on the network of 1m
telescopes at the Cerro Tololo Inter-American Observatory (Chile), the
South African Astronomical Observatory (South Africa), the Siding
Spring Observatory (Australia), and the McDonald Observatory (United
States), through the Global Supernova Project, from 2019 July 4 to
2019 September 20. Reference images were obtained on 2021 December 31,
long after the SN faded. BV-band magnitudes are calibrated to the Vega
system, and gri-band magnitudes to the AB system.
We also obtained c- and o-band host-subtracted photometry of SN2019kbj
from the ATLAS Forced Photometry Server. We find the last
pre-explosion ATLAS 5σ nondetection limit to be on 2019 June 29
at a magnitude of 19.89 in the c band, constraining the explosion time
to a window of only 2 days between 2019 June 29 and 2019 July 1.
We downloaded images of SN 2019kbj taken by the Ultraviolet Optical
Telescope (UVOT) on board the Neil Gehrels Swift Observatory, obtained
under a Target of Opportunity request (PI: Hiramatsu), from the High
Energy Astrophysics Science Archive Research Center (HEASARC).
We obtained 12 spectroscopic observations with the Las Cumbres
Observatory Floyds spectrographs mounted on the 2m Faulkes Telescope
North (FTN) and South (FTS) at the Haleakala (United States) and
Siding Spring (Australia) observatories, respectively, through the
Global Supernova Project.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
22 11 21.93 +19 37 03.4 SN2019kbj = ATLAS 19ohl
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 60 211 Photometry of SN2019kbj
table2.dat 78 12 Log of spectroscopic observations
table4.dat 63 19 Results of blackbody fits to the photometry
of SN 2019kbj
sp/* . 11 Individual spectra in ASCII format of SN 2019kbj
(Data behind Figure 4)
--------------------------------------------------------------------------------
See also:
J/MNRAS/383/1485 : BVRI light curves of SN 2003jd (Valenti+, 2008)
J/AJ/137/4517 : UVOT light curves of supernovae (Brown+, 2009)
J/ApJ/769/39 : SNIbn PS1-12sk optical and NIR light curves (Sanders+, 2013)
J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
J/MNRAS/449/1921 : UV/opt/NIR photometry for Type Ibn SNe (Pastorello+, 2015)
J/MNRAS/449/1941 : Opt/NIR photometry of OGLE-2012-SN-006 (Pastorello+, 2015)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/A+A/602/A93 : SN type Ibn OGLE-2014-SN-131 LCs (Karamehmetoglu+, 2017)
J/A+A/605/A6 : Photometry of supernova iPTF13z (Nyholm+, 2017)
J/ApJ/917/97 : Spectroscopic obs. of type Ibn ASASSN-14ms (Wang+, 2021)
J/ApJ/926/125 : SNIbn with LCO LCs & FLOYDS sp. (Pellegrino+, 2022)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d MJD [58663.49/58715.41] Modified Julian date of
observation (JD-2400000.5)
12- 15 A4 --- Filt Filter
17 A1 --- l_omag Limit flag on omag
19- 36 F18.15 mag omag [16.13/20.8] Magnitude in Filt
38- 57 F20.18 mag e_omag [0.006/0.31]? Uncertainty in omag
59- 60 I2 --- Source [2/10] Source for observation (1)
--------------------------------------------------------------------------------
Note (1): Sources are listed numerically, as follows:
2 = Las Cumbres 1m0-05;
3 = Las Cumbres 1m0-04;
4 = Las Cumbres 1m0-10;
5 = Las Cumbres 1m0-03;
6 = Las Cumbres 1m0-13;
7 = Las Cumbres 1m0-08;
8 = Las Cumbres 1m0-06;
9 = ATLAS;
10 = SWIFT.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 "Y/M/D" Date Date of observation (UT)
12- 19 F8.2 d MJD [58666.68/59722.52] Modified Julian Date
21- 25 F5.2 d Phase [-2.42/35.43]? Phase
27- 32 A6 --- Tel Telescope
34- 73 A40 --- File Name of the ASCII file in subdirectory "sp";
column added by CDS
75- 78 A4 --- Host Host?
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.1 d MJD [58665.5/58705.4] Modified Julian date of fit
(JD-2400000.5)
9- 13 F5.2 d Phase [-3.61/36.3] Phase since 2019 July 1 UT
15- 19 I5 K Temp [9946/19587] Temperature
21- 24 I4 K e_Temp [80/3247] Lower uncertainty on Temp
26- 29 I4 K E_Temp [89/5326] Upper uncertainty on Temp
31- 35 F5.2 10+12m Rad [2.88/13.1] Radius, 10+14cm
37- 40 F4.2 10+12m e_Rad [0.09/1] Lower uncertainty on Rad
42- 45 F4.2 10+12m E_Rad [0.09/1.32] Upper uncertainty on Rad
47- 51 F5.3 10+36W Lum [0.18/4.5] Luminosity, 10+43erg/s
53- 57 F5.3 10+36W e_Lum [0.05/0.71] Lower uncertainty on Lum
59- 63 F5.3 10+36W E_Lum [0.05/0.9] Upper uncertainty on Lum
--------------------------------------------------------------------------------
Byte-by-byte Description of file: sp/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 E24.10 0.1nm lambda [3499/10001] Observed wavelength,
in Angstroms
26- 50 E25.11 cW/m2/nm Flambda [-3e-16/1.2e-15] Flux,
in erg/s/cm2/Angstrom
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 14-Feb-2025