J/ApJ/907/99 Pre-explosion light curve of 227 Supernovae (Strotjohann+, 2021)
Bright, Months-long Stellar Outbursts Announce the Explosion of Interaction-
powered Supernovae.
Strotjohann N.L., Ofek E.O., Gal-Yam A., Bruch R., Schulze S., Shaviv N.,
Sollerman J., Filippenko A.V., Yaron O., Fremling C., Nordin J., Kool E.C.,
Perley D.A., Ho A.Y.Q., Yang Yi, Yao Y., Soumagnac M.T., Graham M.L.,
Barbarino C., Tartaglia L., De K., Goldstein D.A., Cook D.O., Brink T.G.,
Taggart K., Yan L., Lunnan R., Kasliwal M., Kulkarni S.R., Nugent P.E.,
Masci F.J., Rosnet P., Adams S.M., Andreoni I., Bagdasaryan A., Bellm E.C.,
Burdge K., Duev D.A., Dugas A., Frederick S., Goldwasser S., Hankins M.,
Irani I., Karambelkar V., Kupfer T., Liang J., Neill J.D., Porter M.,
Riddle R.L., Sharma Y., Short P., Taddia F., Tzanidakis A., van Roestel J.,
Walters R., Zhuang Z.
<Astrophys. J., 907, 99 (2021)>
=2021ApJ...907...99S 2021ApJ...907...99S
ADC_Keywords: Supernovae; Photometry, VRI
Keywords: Eruptive phenomena ; Stellar mass loss ; Circumstellar matter ;
Late stellar evolution ; Stellar flares ; Core-collapse
supernovae
Abstract:
Interaction-powered supernovae (SNe) explode within an optically thick
circumstellar medium (CSM) that could be ejected during eruptive
events. To identify and characterize such pre-explosion outbursts, we
produce forced-photometry light curves for 196 interacting SNe, mostly
of Type IIn, detected by the Zwicky Transient Facility between early
2018 and 2020 June. Extensive tests demonstrate that we only expect a
few false detections among the 70000 analyzed pre-explosion images
after applying quality cuts and bias corrections. We detect precursor
eruptions prior to 18 Type IIn SNe and prior to the Type Ibn SN
2019uo. Precursors become brighter and more frequent in the last
months before the SN and month-long outbursts brighter than magnitude
-13 occur prior to 25% (5-69%, 95% confidence range) of all Type IIn
SNe within the final three months before the explosion. With radiative
energies of up to 1049erg, precursors could eject ∼1M☉ of
material. Nevertheless, SNe with detected precursors are not
significantly more luminous than other SNe IIn, and the characteristic
narrow hydrogen lines in their spectra typically originate from
earlier, undetected mass-loss events. The long precursor durations
require ongoing energy injection, and they could, for example, be
powered by interaction or by a continuum-driven wind. Instabilities
during the neon- and oxygen-burning phases are predicted to launch
precursors in the final years to months before the explosion; however,
the brightest precursor is 100 times more energetic than anticipated.
Description:
The commissioning phase of the Zwicky Transient Facility (ZTF) survey
started in fall 2017, while the survey officially began in spring 2018
after commissioning and building reference images.
The forced-photometry pipeline was implemented by Yao+, 2019,
J/ApJ/886/152. It relies on the IPAC difference images and the
measured point-spread functions (PSFs; see part2.2 of the article).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 227 SNe with detected pre-explosion activity
table2.dat 95 70420 Forced photometry pre-explosion light curves
table4.dat 58 37 Detected precursors
table6.dat 84 39 SN spectra
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See also:
J/ApJ/737/101 : AGN pairs from SDSS-DR7. I. (Liu+, 2011)
J/ApJ/756/173 : Photometry of type IIn SNe 2005ip & 2006jd (Stritzinger+, 2012)
J/ApJ/763/L27 : RI light curves of the type IIn SN 2009ip (Prieto+, 2013)
J/ApJ/768/47 : Swift/XRT 0.2-10keV observations of SN2009ip (Ofek+, 2013)
J/ApJ/769/39 : SN Ibn PS1-12sk optical and NIR light curves (Sanders+, 2013)
J/other/Nat/494.65 : SN 2010mc outburst before explosion (Ofek+, 2013)
J/ApJ/781/42 : Optical photometry of SN 2010jl (Ofek+, 2014)
J/ApJ/789/104 : SNe IIn observations and properties (Ofek+, 2014)
J/ApJ/811/117 : R-band PTF observations of SNe IIb (Strotjohann+, 2015)
J/ApJ/824/6 : PTF obs. precursor to SNHunt 275 2015 May event (Ofek+, 2016)
J/A+A/605/A6 : Photometry of supernova iPTF13z (Nyholm+, 2017)
J/A+A/631/A147 : Transient processing and analysis using AMPEL (Nordin+, 2019)
J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)
J/ApJ/887/169 : UV-Opt light curves of the type Ic SN 2018gep (Ho+, 2019)
J/A+A/637/A73 : Type IIn supernova photometry (Nyholm+, 2020)
J/ApJ/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 2020)
J/A+A/652/A136 : SN 2020bqj light curves (Kool+, 2021)
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- IAU IAU name (1)
12- 23 A12 --- ZTF ZTF name
25- 31 A7 --- SpT SN Type
33- 44 F12.8 deg RAdeg [1/356] Right Ascension (J2000) (2)
46- 57 F12.8 deg DEdeg [-21/80] Declination (J2000) (2)
59- 66 F8.6 --- zspec [0.005/0.37] Spectroscopic redshift
68- 76 F9.1 d Date [2458195/2458976] Estimated explosion date,
Julian Date (3)
78- 81 F4.1 arcsec Sep [0/65]? Separation from host galaxy
83-112 A30 --- Note Comments
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Note (1): SNe without a listed spectra type are discarded.
Note (2): The RAdeg and DEdeg values represent the median coordinates of at
least 10 ZTF detections.
Note (3): Either the first detection time announced on TNS or a smaller value
if the transient flux is visible earlier in ZTF data.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- IAU IAU name
14- 25 A12 --- ZTF ZTF name
27- 41 F15.7 d JD [2458041/2458964] Julian Date of observation
43- 46 A4 --- Band [gri] ZTF band
48- 55 A8 --- refim ID of used reference image (1)
57- 65 E9.2 mag Flux [-6.35e-08/3.37e-08] Flux (2)
67- 74 E8.2 mag e_Flux [6e-11/6e-08] Uncertainty in Flux (2)
77- 84 E8.2 --- Fluxerr [7e-11/4e-10] Sys. flux error from ref. image (3)
87- 90 F4.2 --- chi2 [0.05/1.4] Red. chi2 of PSF fit as SN position
92- 95 F4.2 --- chi2* [0.0/1.4] Red. chi2 of PSF fit for nearby star
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Note (1): The reference image was used (e.g. for the first rows the image for
the ZTF field 575, CCD 12, quadrant 3 and filter 2, the r band;
see also Yao+, 2019, J/ApJ/886/152.
Note (2): Corrected for the zeropoint and are given as a dimensionless
ratio (see Eq. 8 in Yao+,2019, J/ApJ/886/152). This flux ratio is also
known as "maggie" (Finkbeiner+, 2004AJ....128.2577F 2004AJ....128.2577F).
Note (3): The noise level in the reference image which is a systematic
error on the measured flux.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- IAU IAU name
13 A1 --- Band [gri] Band of observation
15- 20 F6.1 d Phase.s [-693/-6] Phase start
22- 27 F6.1 d Phase.e [-546/0] Phase end
29- 33 F5.1 mag Flux [-16.9/-12.9] Median flux
35- 38 I4 erg E [3/1000] Energy (1046erg)
40- 43 I4 km/s Vcsm [150/1100]? Circonstellar medium velocity (1)
45- 49 F5.3 Msun Mcsm [0.007/7]? Circonstellar medium mass
51- 52 I2 d Trise [4/25]? Time it takes the SN to rise
54 A1 --- l_DMcsm [<] Limit flag on DMcsm
56- 58 F3.1 Msun DMcsm [0.4/2.5]? CSM mass difference
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Note (1): The CSM velocity is derived from the median width of the
narrow lines and PCygni profiles (see Section 5.1) and is used to
estimate the CSM mass multiplied by an unknown efficiency factor
ε.Trise quantifies how many days it takes the SN to rise by
a factor of e (1.086mag) to its peak in the r band (g band used for
SN2018gho and SN2019iay).
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- IAU IAU Name
13- 21 F9.1 d JD [2458351/2458931] Julian date of observation
23- 41 A19 --- Inst Instrument used
43- 46 F4.1 d dT [2.7/78.6] Time after explosion
48- 51 I4 km/s LW [200/1500]? Line width
53- 55 I3 km/s Res [130/980]? Instrument resolution (1)
57 A1 --- l_Vel1 [<] Limit flag on Vel1
59- 62 I4 km/s Vel1 [160/1342] Velocity 1
64- 67 I4 km/s Vel2 [750/1050]? Velocity 2
69 A1 --- f_Vel1 [ah] Flag on Vel1 and/or Vel2 (2)
71- 84 A14 --- Note Additional comment
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Note (1): The typical resolution or the spectrograph is subtracted
from the measured width in quadrature, or we quote an upper limit if
the result would be smaller than half the resolution. For most SNe,
additional low-resolution spectra were obtained with the SED Machine.
Note (2): Flags as follows:
a = velocities measured from P Cygni profiles and not from line widths
(11 occurrences)
h = strong host lines such that the measured velocities are less reliable
(6 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 15-Jun-2022