J/ApJ/958/178 SN 2022joj optical and UV photometry follow-up (Liu+, 2023)
SN 2022joj: a peculiar type Ia supernova possibly driven by an asymmetric
helium-shell double detonation.
Liu C., Miller A.A., Boos S.J., Shen K.J., Townsley D.M., Schulze S.,
Harvey L., Maguire K., Johansson J., Brink T.G., Burgaz U.,
Dimitriadis G., Filippenko A.V., Hall S., Hinds K.-R., Hoffman A.,
Karambelkar V., Kilpatrick C.D., Perley D., Pichay N., Sears H.,
Sollerman J., Stein R., Terwel J.H., Zheng W., Graham M.J., Kasliwal M.M.,
Lacroix L., Purdum J., Rusholme B., Wold A.
<Astrophys. J., 958, 178 (2023)>
=2023ApJ...958..178L 2023ApJ...958..178L
ADC_Keywords: Photometry, UBVRI; Ultraviolet
Keywords: Supernovae ; Type Ia supernovae ; White dwarf stars ;
Observational astronomy ; Surveys
Abstract:
We present observations of SN 2022joj, a peculiar Type Ia supernova
discovered by the Zwicky Transient Facility. SN 2022joj exhibits an
unusually red gZTF-rZTF color at early times and a rapid blueward
evolution afterward. Around maximum brightness, SN 2022joj shows a
high luminosity (MgZTF,max~-19.7mag), a blue broadband color
(gZTF-rZTF~-0.2mag), and shallow SiII absorption lines, consistent
with those of overluminous, SN 1991T-like events. The maximum-light
spectrum also shows prominent absorption around 4200Å, which
resembles the TiII features in subluminous, SN 1991bg-like events.
Despite the blue optical-band colors, SN 2022joj exhibits extremely
red ultraviolet minus optical colors at maximum luminosity (u-v∼0.6mag
and uvw1-v∼2.5mag), suggesting a suppression of flux at
∼2500-4000Å. Strong CII lines are also detected at peak. We show
that these unusual spectroscopic properties are broadly consistent
with the helium-shell double detonation of a sub-Chandrasekhar mass
(M∼1M☉) carbon/oxygen white dwarf from a relatively massive
helium shell (Ms∼0.04-0.1M☉), if observed along a line of sight
roughly opposite to where the shell initially detonates. None of the
existing models could quantitatively explain all the peculiarities
observed in SN 2022joj. The low flux ratio of [NiII]λ7378 to
[FeII]λ7155 emission in the late-time nebular spectra indicates
a low yield of stable Ni isotopes, favoring a sub-Chandrasekhar mass
progenitor. The significant blueshift measured in the [FeII]λ7155
line is also consistent with an asymmetric chemical distribution in
the ejecta, as is predicted in double-detonation models.
Description:
SN 2022joj was discovered by the Zwicky Transient Facility (ZTF) on
2022 May 08.298 (UTC; MJD59707.298) with the 48 inch Samuel Oschin
Telescope (P48) at Palomar Observatory.
Follow-up observations of the SN were coordinated using the Fritz
marshal (van der Walt+ 2019JOSS....4.1247V 2019JOSS....4.1247V;
Coughlin+ 2023ApJS..267...31C 2023ApJS..267...31C).
SN 2022joj was also independently monitored by the Asteroid
Terrestrial-impact Last Alert System (ATLAS).
The first spectrum was obtained on 2022 May 11.288 by
Newsome+ (2022TNSCR2167....1N 2022TNSCR2167....1N), who found a best fit to a young Type I
SN at redshift z=0.03. Chu+ (2022TNSCR..36....1C 2022TNSCR..36....1C) used a peak-luminosity
spectrum to indisputably classify SN 2022joj as an SN Ia based on its
blue color and persistent SiII features.
See Section 2.1.
The host of SN 2022joj is a dwarf galaxy at
RAJ2000=14:41:40.04,DEJ2000=+03:00:24.53, as cataloged in the DESI
Legacy Imaging Survey (LS; Dey+ 2019AJ....157..168D 2019AJ....157..168D), which reports
3σ detections in grz and W1 (see Table 1). SN 2022joj has a
projected offset of only 0.5"±0.1" from the host (corresponding to a
projected distance of 0.27±0.05kpc at the estimated redshift.
To determine the redshift of the host, we obtained two spectra about
300 days after the SN maximum brightness. On 2023 March 14, we took a
spectrum of both the SN and the host using Binospec on the 6.5m MMT
telescope with a total integration time of 5400s.
On 2023 April 26, we took another spectrum using the Low Resolution
Imaging Spectrometer (LRIS) on the Keck I 10m telescope.
See Section 2.2.
SN 2022joj was monitored in ZTF's gri bands as part of its ongoing
Northern Sky Survey (Bellm+ 2019PASP..131f8003B 2019PASP..131f8003B).
Additional observations of SN 2022joj were obtained in the o and c
filters in the ATLAS survey, in the griz filters with the optical
imaging component of the infrared-Optical suite of instruments (IO:O)
on the Liverpool Telescope (LT), in the griBVRI filters and the clear
filter on the 0.76m Katzman Automatic Imaging Telescope (KAIT) at Lick
Observatory, and in the BVRI filters on the 1m Anna Nickel telescope
at Lick.
See Section 2.3.
UV observations of SN 2022joj were obtained using the
Ultraviolet/Optical Telescope (UVOT) on the Neil Gehrels Swift
Observatory (Swift) following a target-of-opportunity request by E.
Padilla Gonzalez. See Section 2.4.
We obtained a series of optical spectra of SN 2022joj using the
Spectral Energy Distribution Machine (SEDM) on the automated 60 inch
telescope (P60) at Palomar Observatory, the Kast double spectrograph
on the Shane 3m telescope at Lick Observatory, the Andalucia Faint
Object Spectrograph and Camera (ALFOSC) installed at the 2.56m Nordic
Optical Telescope (NOT), the Spectrograph for the Rapid Acquisition of
Transients (SPRAT) on the 2m LT under program PL22A13 (PI: Dimitriadis),
the FLOYDS spectrograph on the 2m Faulkes Telescope South (FTS) at
Siding Spring as part of the Las Cumbres Observatory (LCO), Binospec
on the 6.5m MMT telescope, and LRIS on the Keck I 10m telescope.
See Section 2.5
The data utilized in this study are available online at Zenodo under
an open-source Creative Commons attribution license,
doi:10.5281/zenodo.8331024, and at our GitHub repository,
https://github.com/slowdivePTG/SN2022joj
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
14 41 40.05 +03 00 24.3 SN 2022joj = ZTF22aajijjf
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 45 442 Optical and UV photometry of SN2022joj
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See also:
J/AJ/135/1598 : Optical spectroscopy of type Ia supernovae (Matheson+, 2008)
J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)
J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)
J/ApJ/787/29 : UVOT phot. of Super-Chandrasekhar mass SNe Ia (Brown+, 2014)
J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)
J/A+A/630/A76 : SN2016hnk photometry and spectroscopy (Galbany+, 2019)
J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)
J/ApJ/902/48 : ZTF early obs. of type Ia supernovae. III. (Bulla+, 2020)
J/ApJ/905/58 : Local ZTF universe. I. Ca-rich gap transients (De+, 2020)
J/ApJ/891/85 : Manganese abund. in GC & dSph galaxies (de los Reyes+, 2020)
J/MNRAS/491/2902 : Sub-Chandrasekhar progenitors for Type Ia SNe (Flors+, 2020)
J/ApJ/896/165 : Optical light curves of SN 2016hnk (Jacobson-Galan+, 2020)
J/ApJ/902/47 : ZTF early obs. of type Ia SNe. II. Rise time (Miller+, 2020)
J/ApJS/255/29 : PTF core-collapse SN host-galaxy sample. I. (Schulze+, 2021)
J/ApJ/934/102 : Follow-up LCO phot. & spectra of SN 2016dsg (Dong+, 2022)
J/ApJ/946/7 : BVI light curves and sp. of Type Ia SN 2018aoz (Ni+, 2023)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 d MJD [59707.2/59804.2] Observation date
(JD-2400000.5)
11- 16 A6 --- Filter Filter (1)
18- 23 F6.3 mag omag [15.8/21] Observed magnitude in Filter (2)
25- 29 F5.3 mag e_omag [0.005/0.9] Uncertainty in omag
31- 34 A4 --- n_omag Magnitude System, AB or Vega
36- 45 A10 --- Tel Telescope used (3)
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Note (1): Observed magnitudes are in the ZTF, ATLAS, UVOT, LT, KAIT, and Nickel
passbands.
Note (2): Correction for Galactic extinction has not been applied.
Note (3): Telescope used as follows:
ATLAS = The Asteroid Terrestrial-impact Last Alert System
(215 occurrences)
P48/ZTF = The 48 inch Samuel Oschin Telescope at Palomar Observatory
with the Zwicky Transient Facility (96 occurrences)
KAIT = The 0.76m Katzman Automatic Imaging Telescope (64 occurrences)
Nickel = The 1m Anna Nickel telescope at Lick Observatory (28 occurrences)
Swift/UVOT = The Swift Ultraviolet/Optical Telescope (23 occurrences)
LT = The 2m Liverpool Telescope with the IO:O instruments
(16 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 26-Jan-2026