J/ApJ/952/119 SNII during ZTF 1st phase survey with follow-up sp. (Bruch+, 2023)
The prevalence and influence of circumstellar material around hydrogen-rich
supernova progenitors.
Bruch R.J., Gal-Yam A., Yaron O., Chen P., Strotjohann N.L., Irani I.,
Zimmerman E., Schulze S., Yang Yi, Kim Y.-L., Bulla M., Sollerman J.,
Rigault M., Ofek E., Soumagnac M., Masci F.J., Fremling C., Perley D.,
Nordin J., Cenko S.B., Ho A.Y.Q., Adams S., Adreoni I., Bellm E.C.,
Blagorodnova N., Burdge K., De K., Dekany R.G., Dhawan S., Drake A.J.,
Duev D.A., Graham M., Graham M.L., Jencson J., Karamehmetoglu E.,
Kasliwal M.M., Kulkarni S., Miller A.A., Neill J.D., Prince T.A.,
Riddle R., Rusholme B., Sharma Y., Smith R., Sravan N., Taggart K.,
Walters R., Yan L.
<Astrophys. J., 952, 119 (2023)>
=2023ApJ...952..119B 2023ApJ...952..119B
ADC_Keywords: Supernovae; Photometry; Optical; Magnitudes, absolute;
Spectra, optical; Redshifts
Keywords: Core-collapse supernovae ; Type II supernovae ; Supernovae ;
Massive stars ; Circumstellar matter
Abstract:
Narrow transient emission lines (flash-ionization features) in early
supernova (SN) spectra trace the presence of circumstellar material
(CSM) around the massive progenitor stars of core-collapse SNe. The
lines disappear within days after the SN explosion, suggesting that
this material is spatially confined, and originates from enhanced mass
loss shortly (months to a few years) prior to the explosion. We
performed a systematic survey of H-rich (Type II) SNe discovered
within less than 2 days from the explosion during the first phase of
the Zwicky Transient Facility survey (2018-2020), finding 30 events
for which a first spectrum was obtained within <2 days from the
explosion. The measured fraction of events showing flash-ionization
features (>36% at the 95% confidence level) confirms that elevated
mass loss in massive stars prior to SN explosion is common. We find
that SNe II showing flash-ionization features are not significantly
brighter, nor bluer, nor more slowly rising than those without. This
implies that CSM interaction does not contribute significantly to
their early continuum emission, and that the CSM is likely optically
thin. We measured the persistence duration of flash-ionization
emission and find that most SNe show flash features for ∼5 days. Rarer
events, with persistence timescales >10 days, are brighter and rise
longer, suggesting these may be intermediate between regular SNe II
and strongly interacting SNe IIn.
Description:
We constructed our sample through both real-time data scanning and
complementary archival search. We consider SNe detected and classified
by ZTF-I, i.e., between 2018 March and 2020 December, and restrict our
search to spectroscopically classified SNe II, IIn, and IIb.
The final sample (see Tables 7-9 in the Appendix) is composed of 148
SNe discovered between 2018 March and 2020 December.
We present, in Section 2.2, the spectroscopic facilities we used
during our search for infant SNe II. In brief, we used:
The Spectral Energy Distribution Machine (SEDm) on the 60" robotic
telescope (P60) at Palomar Observatory.
The Spectrograph for the Rapid Acquisition of Transients (SPRAT) on
the 2m Liverpool Telescope (LT) at the Observatorio del Roque de Los
Muchachos in Spain.
The Double Beam SPectrograph (DBSP) on the 5m Hale telescope at
Palomar Observatory (P200).
The 4.2m William Herschel Telescope (WHT) at the Observatorio del
Roque de los Muchachos in La Palma, Spain, via the Optical Infrared
Coordination Network for Astronomy (OPTICON) program.
The Low-Resolution Imaging Spectrometer (LRIS) mounted on the Keck I
10m telescope at the W. M. Keck Observatory in Hawaii.
The Gemini Multi-Object Spectrograph (GMOS) on the Gemini North 8m
telescope at the Gemini Observatory on Maunakea, Hawaii.
The Dual Imaging Spectrograph (DIS) on the Astrophysical Research
Consortium (ARC) 3.5m telescope at Apache Point Observatory (APO).
The Andalucia Faint Object Spectrograph and Camera (ALFOSC) mounted on
the 2.56m Nordic Optical Telescope (NOT).
The FOcal Reducer/low dispersion Spectrograph 2 on the Very Large
Telescope (ESO-VLT Large Program 1104.A-0380).
The X-Shooter on VLT with the UVB, VIS and NIR spectrographs.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 187 120300 ZTF/P48 forced-photometry light curves of the
148 events in the Real Infant sample
table2.dat 46 28 Sample of infant hydrogen rich objects which showed
flash ionisation features
table3.dat 29 13 SNR estimation of the first spectra obtained with
SEDm in the 2-day subsample
table4.dat 72 34 Subsample of SN II objects with a first spectrum
≤2d from EED
table5.dat 88 38 Timescales of flash-ionisation features, peak
absolute magnitudes in r band and g band
table7.dat 96 127 Hydrogen rich normal SNe II
table8.dat 95 11 Real infants classified as SN IIn
table9.dat 95 10 Real infants classified as SN IIb
--------------------------------------------------------------------------------
See also:
J/ApJ/736/159 : Photometry monitoring of the SN PTF10vdl (Gal-Yam+, 2011)
J/other/Nat/494.65 : SN 2010mc outburst before explosion (Ofek+, 2013)
J/ApJ/789/104 : SNe IIn observations and properties (Ofek+, 2014)
J/ApJ/820/33 : R-band light curves of type II supernovae (Rubin+, 2016)
J/ApJ/861/63 : Type IIP SN 2016bkv LCs and spectra (Hosseinzadeh+, 2018)
J/A+A/631/A147 : Transient processing & analysis using AMPEL (Nordin+, 2019)
J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)
J/A+A/637/A73 : Type IIn supernova photometry (Nyholm+, 2020)
J/ApJ/902/6 : UV to visible-light obs. of SN 2018fif (Soumagnac+, 2020)
J/ApJ/912/46 : ZTF Type II supernovae with follow-up obs. (Bruch+, 2021)
J/ApJ/907/99 : Pre-explosion light curve of 227 SNe (Strotjohann+, 2021)
J/ApJ/924/15 : Final moments. I. Type II SN 2020tlf (Jacobson-Galan+, 2022)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 26 F26.21 d Time [-972.6/1081] Time from the estimated explosion
date (EED)
28- 42 F15.7 d JD Julian Date of observation
44- 66 E23.7 3631Jy Flux [-4.15e-08/4e-07] Flux, in Mgy
68- 89 E22.7 3631Jy e_Flux [2.2e-11/2.6e-08] Uncertainty in Flux, in Mgy
91- 108 F18.15 mag omag [15.99/21]?=99 Apparent magnitude in Filt
110- 130 F21.18 mag e_omag [0.013/0.4]?=99 Uncertainty in omag
132- 150 F19.15 mag MAG [-20.41/-10.99]?=99 Absolute magnitude in Filt
152- 172 F21.18 mag e_MAG [0.016/1.4]?=99 Uncertainty in MAG
174 A1 --- Filt [gr] Filter
176- 178 A3 --- --- [ZTF]
179- 187 A9 --- ZTF ZTF Name (YYaaaaaaa)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU name (YYYYaaa)
10- 15 A6 --- Type SN Type
17- 19 A3 --- Flash Flasher yes, no
21- 31 A11 --- Inst Instrument+Telescope of 1st spectrum
33- 37 F5.2 d Date1sp [0.14/11.4] First spectrum, days since estimated
explosion date (EED)
39- 46 A8 --- Res Spectrograph Resolution (1)
--------------------------------------------------------------------------------
Note (1): Spectrograph resolution as follows:
very low = R<300;
low = 300<R≤390;
medium = 390<R.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU name (YYYYaaa)
10- 12 A3 --- Flash Flasher yes, no
14- 17 F4.2 d Date1sp [0.1/1.94] First spectrum, days since estimated
explosion date (EED)
19- 23 F5.2 mag omag [17.44/19.6] Apparent (AB) mag at Date1sp
25- 29 F5.2 --- SNR [3.15/24.09] Signal-to-noise of 1st spectrum
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU Name (YYYYaaa)
10- 13 A4 --- Flash Flasher? yes, yes?, no
15- 18 F4.2 d Date1sp [0.11/1.99] First spectrum, days from
estimated explosion date (EED)
20- 30 A11 --- Inst Instrument+Telescope of 1st spectrum
32- 36 F5.3 --- zspec [0.012/0.058] Spectroscopic redshift
38- 38 A1 --- lezspec Limit flag on e_zspec
40- 45 F6.4 --- e_zspec [0.0001/0.0108] Uncertainty on zspec
47- 47 A1 --- Filt Filter bandpass name
49- 54 F6.2 mag MAGpk [-18.75/-14.51]? Peak absolute (AB)
magnitude in Filt
56- 56 A1 --- leMAGpk Limit flag on MAGpk
58- 61 F4.2 mag e_MAGpk [0.01/0.41]? Uncertainty in MAGpk
63- 67 F5.2 d Rise [4.72/24.76]? Rise time
69- 72 F4.2 d e_Rise [0.11/1.93]? Uncertainty in Rise
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU Name (YYYYaaa)
10- 15 A6 --- Type SN Type
17- 25 F9.1 d JD-last Julian date of last flash
27- 35 F9.1 d JD-no Julian date of no flash
37- 41 F5.2 d tau [1.28/17.15] characteristic timescale
43- 46 F4.2 d e_tau [0.5/6.51] Uncertainty on tau
48- 52 F5.3 --- zspec [0.012/0.08] Spectroscopic redshift
54- 54 A1 --- lezspec Limit flag on e_zspec
56- 61 F6.4 --- e_zspec [0.0001/0.01] Uncertainty on zspec
63- 63 A1 --- Filt Filter bandpass name
65- 70 F6.2 mag MAGpk [-20.37/-14.51]? Peak absolute (AB)
magnitude in Filt
72- 72 A1 --- leMAGpk Limit flag on MAGpk
74- 77 F4.2 mag e_MAGpk [0.01/0.5]? Uncertainty in MAGpk
79- 83 F5.2 d Rise [1.72/24.65]? Rise time (days)
85- 88 F4.2 d e_Rise [0.1/1.7]? Uncertainty in Rise
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU Name (YYYYaaa)
10- 12 A3 --- --- [ZTF]
13- 21 A9 --- ZTF ZTF Name (YYaaaaaaa)
23- 28 A6 --- Type SN Type (always "SN II")
30- 40 F11.3 d EED Estimated Julian Date of Explosion
42- 46 F5.3 d e_EED [0.001/5.7] Uncertainty in EED
48- 53 F6.3 d DateLst [-7.9/4.1] Last non-detection, days to EED (G1)
55- 59 F5.3 d DateFst [0/5.2] First detection, days from EED (G1)
61- 71 F11.7 deg RAdeg Right Ascension (J2000)
73- 84 F12.8 deg DEdeg [-25.5/81.3] Declination (J2000)
86- 91 F6.3 d Date1sp [0.1/94.5] First spectrum, days from EED (G1)
93- 96 A4 --- Flash Flasher? yes, yes?, no
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU Name (YYYYaaa)
10- 12 A3 --- --- [ZTF]
13- 21 A9 --- ZTF ZTF Name (YYaaaaaaa)
23- 28 A6 --- Type SN Type (always "SN IIn")
30- 40 F11.3 d EED Estimated Julian Date of Explosion
42- 46 F5.3 d e_EED [0.028/1.6] Uncertainty in EED
48- 53 F6.3 d DateLst [-1.52/1.1] Last non-detection,
days to EED (G1)
55- 59 F5.3 d DateFst [0.005/2.1] First detection, days from EED (G1)
61- 71 F11.7 deg RAdeg [38.29/353.7] Right Ascension (J2000)
73- 84 F12.8 deg DEdeg [-1.31/74.4] Declination (J2000)
86- 91 F6.3 d Date1sp [1.15/39.12] First spectrum, days from EED (G1)
93- 95 A3 --- Flash Flasher? yes, no
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN IAU Name (YYYYaaa)
10- 12 A3 --- --- [ZTF]
13- 21 A9 --- ZTF ZTF Name (YYaaaaaaa)
23- 28 A6 --- Type SN Type (always "SN IIb")
30- 40 F11.3 d EED Estimated Julian Date of Explosion
42- 46 F5.3 d e_EED [0.003/1] Uncertainty in EED
48- 53 F6.3 d DateLst [-1.76/0.07] Last non-detection,
days to EED (G1)
55- 59 F5.3 d DateFst [0.015/1] First detection, days from EED (G1)
61- 71 F11.7 deg RAdeg [2.69/298] Right Ascension (J2000)
73- 84 F12.8 deg DEdeg [3.3/70.5] Declination (J2000)
86- 91 F6.3 d Date1sp [0.57/15] First spectrum, days from EED (G1)
93- 95 A3 --- Flash Flasher? yes, no
--------------------------------------------------------------------------------
Global notes:
Note (G1): The dates of the Last non-detection ("DateLst"),
First detection ("DateFst") and first spectrum ("Date1sp") are given as
differences from the estimated date of explosion (EED).
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 15-Sep-2025