J/ApJ/933/L45 LCs and spectra of type Ia SN 2021aefx (Hosseinzadeh+, 2022)
Constraining the progenitor system of the type Ia supernova 2021aefx.
Hosseinzadeh G., Sand D.J., Lundqvist P., Andrews J.E., Bostroem K.A.,
Dong Y., Janzen D., Jencson J.E., Lundquist M., Meza Retamal N.E.,
Pearson J., Valenti S., Wyatt S., Burke J., Howell D.A., McCully C.,
Newsome M., Gonzalez E.P., Pellegrino C., Terreran G., Kwok L.A.,
Jha S.W., Strader J., Kundu E., Ryder S.D., Haislip J., Kouprianov V.,
Reichart D.E.
<Astrophys. J., 933, L45 (2022)>
=2022ApJ...933L..45H 2022ApJ...933L..45H
ADC_Keywords: Supernovae; Photometry, UBVRI; Spectra, optical
Keywords: Binary stars ; Supernovae ; Type Ia supernovae ; White dwarf stars
Abstract:
We present high-cadence optical and ultraviolet light curves of the
normal Type Ia supernova (SN) 2021aefx, which shows an early bump
during the first two days of observation. This bump may be a signature
of interaction between the exploding white dwarf and a nondegenerate
binary companion, or it may be intrinsic to the white dwarf explosion
mechanism. In the case of the former, the short duration of the bump
implies a relatively compact main-sequence companion star, although
this conclusion is viewing-angle dependent. Our best-fit
companion-shocking and double-detonation models both overpredict the
UV luminosity during the bump, and existing nickel-shell models do not
match the strength and timescale of the bump. We also present nebular
spectra of SN 2021aefx, which do not show the hydrogen or helium
emission expected from a nondegenerate companion, as well as a radio
nondetection that rules out all symbiotic progenitor systems and most
accretion disk winds. Our analysis places strong but conflicting
constraints on the progenitor of SN 2021aefx; no current model can
explain all of our observations.
Description:
SN 2021aefx was discovered by the Distance Less Than 40Mpc (DLT40)
survey (Tartaglia+ 2018ApJ...853...62T 2018ApJ...853...62T) on 2021-11-11.343 UT at an
unfiltered brightness of 17.25±0.05mag and was not detected on
2021-11-06.328 UT to an unfiltered limit of 19.35mag.
We immediately initiated a high-cadence photometric follow-up campaign
using the 1m and 0.4m telescope networks of Las Cumbres Observatory
and the Ultraviolet/Optical Telescope (UVOT) on the Neil Gehrels Swift
Observatory.
We also obtained optical spectroscopy of SN 2021aefx using the FLOYDS
spectrograph on Las Cumbres Observatory's 2m Faulkes Telescope South
(FTS), the High Resolution Spectrograph (HRS) and the Robert Stobie
Spectrograph (RSS) on the South African Large Telescope (SALT), and
the Goodman High-Throughput Spectrograph on the Southern Astrophysical
Research Telescope (SOAR).
We also include the public classification spectrum of
Onori+ (2021TNSCR3899....1O 2021TNSCR3899....1O) from the ESO Faint Object Spectrograph
and Camera 2 (EFOSC2) on the New Technology Telescope (NTT).
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
04 19 53.40 -54 56 53.0 SN 2021aefx = SN 2021aefx
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
fig1.dat 45 1327 Light curve of SN 2021aefx
table1.dat 85 47 Log of spectroscopic observations
sp/* . 47 Individual spectra in FITS format
(Data behind Figure 2)
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See also:
J/ApJ/659/122 : Improved distances to type Ia supernovae (Jha+, 2007)
J/ApJ/745/74 : Pre-maximum spectra of type Ia SNe (Folatelli+, 2012)
J/other/Sci/340.170 : Classifications of 188 SNe Ia (Wang+, 2013)
J/MNRAS/440/696 : HI absorption in nearby radio galaxies (Allison+, 2014)
J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJS/235/23 : LEGUS galaxies1 observations (Sabbi+, 2018)
J/ApJ/853/62 : Opt. and NIR spectra and LCs of SN2016ija (Tartaglia+, 2018)
J/ApJ/870/L1 : K2 obs. of type Ia supernova SN 2018oh (Dimitriadis+, 2019)
J/ApJ/870/13 : K2 LC alternative analysis of ASASSN-18bt (Shappee+, 2019)
J/A+A/634/A37 : TURTLS Light curves of 56Ni distributions (Magee+, 2020)
J/ApJ/898/56 : UVOT, ZTF gri LCs & sp. of the SN Ia 2019yvq (Miller+, 2020)
J/MNRAS/493/1044 : Nebular spectra of 111 Type Ia supernovae (Tucker+, 2020)
J/ApJ/923/L8 : Follow-up phot. & sp. of SNIa 2020hvf (Jiang+, 2021)
J/ApJ/922/21 : Type Ia SN 2020nlb opt. photometry & spectra (Sand+, 2021)
J/ApJ/914/50 : Opt. phot. and GMOS & NIRES sp. of SN2019yvq (Tucker+, 2021)
J/ApJ/914/57 : Opt. & NIR obs. of the SNIa SN2015bp (Wyatt+, 2021)
J/ApJ/926/98 : Type Ia supernovae with GALEX observations (Dubay+, 2022)
http://www.wis-tns.org/ : Transient Name Server (TNS) homepage
Byte-by-byte Description of file: fig1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 d MJD [59529.3/59699.5] Modified Julian Date
(JD-2400000.5)
11- 14 A4 --- Filt Filter (1)
16 A1 --- l_omag Limit flag on omag
19- 23 F5.2 mag omag [11.69/20.42] Apparent Magnitude in Filter
25- 28 F4.2 mag e_omag [0/0.31]? Uncertainty in omag
30- 45 A16 --- Tel Telescope (2)
--------------------------------------------------------------------------------
Note (1): The DLT40 measurements are unfiltered
Note (2): Telescope as follows:
DLT40 = the Distance Less Than 40Mpc survey
(Tartaglia+ 2018ApJ...853...62T 2018ApJ...853...62T; 163 occurrences)
Las Cumbres 0.4m = the Las Cumbres Observatory's 0.4m telescope
(310 occurrences)
Las Cumbres 1m = the Las Cumbres Observatory's 1m telescope (692 occurrences)
Swift = the Neil Gehrels Swift Observatory (162 occurrences)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 d MJD [59529.8/59681.4] Modified Julian Date
14- 17 A4 --- Tel Telescope (1)
23- 29 A7 --- Inst Instrument
35- 40 F6.1 d Phase [-16.6/134.2] Phase
42 A1 --- f_Phase Flag on Phase (2)
44- 85 A42 --- FileName Name of the FITS file in subdirectory "sp";
column added by CDS
--------------------------------------------------------------------------------
Note (1): Telescope as follows:
FTS = the Las Cumbres Observatory's 2m Faulkes Telescope South
(19 occurrences)
SALT = the South African Large Telescope (15 occurrences)
SOAR = the Southern Astrophysical Research Telescope (5 occurrences)
NTT = the New Technology Telescope (1 occurrence)
Note (2): Flag as follows:
a = The spectrum presented here is a rereduction of the data published
by Bostroem+ (2021TNSCR3888....1B 2021TNSCR3888....1B) on the Transient Name Server.
b = For the Phase=-15.2, MJD=59531.266, NTT/EFOSC2 spectrum
listed in Table 1, please see Onori+ (2021TNSCR3899....1O 2021TNSCR3899....1O) and find
the data available at http://www.wis-tns.org/object/2021aefx
--------------------------------------------------------------------------------
History:
From electronic version of the journal
Phase=-15.2, MJD=59531.266, NTT/EFOSC2 spectrum downloaded from:
http://www.wis-tns.org/object/2021aefx
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Mar-2025