J/A+A/657/A64 Supernovae ZTF light curves (Sollerman+, 2022)
Maximum luminosities of normal stripped-envelope supernovae are brighter than
explosion models allow.
Sollerman J., Yang S., Perley D., Schulze S., Fremling C., Kasliwal M.,
Shin K., Racine B.
<Astron. Astrophys. 657, A64 (2022)>
=2022A&A...657A..64S 2022A&A...657A..64S (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, SDSS ; Spectroscopy
Keywords: surveys - supernovae: general
Abstract:
Stripped-envelope supernovae (SE SNe) of Type Ib and Type Ic are
thought to result from explosions of massive stars having lost their
outer envelopes. The favoured explosion mechanism is by core-collapse,
with the shock later revived by neutrino heating. However, there is an
upper limit to the amount of radioactive 56Ni that such models can
accomplish. Recent literature point to a tension between the maximum
luminosity from such simulations and observations. We use a well
characterized sample of SE SNe from the Zwicky Transient Facility
(ZTF) Bright Transient Survey (BTS). We scrutinize the observational
caveats regarding estimating the maximum luminosity (and thus the
amount of ejected radioactive nickel) for the members of this sample.
We employ the strict selection criteria for the BTS to collect a
sample of spectroscopically classified normal Type Ibc SNe for which
we use the ZTF light curves to determine the maximum luminosity. We
cull the sample further based on data quality, light-curve shape,
distance and colors, and examine uncertainties that may affect the
numbers. The methodology of the sample construction from this BTS
sample can be used for many other future investigations. We analyze
observational data, consisting of optical light curves and spectra,
for the selected sub-samples. In total we use 129 Type Ib or Type Ic
BTS SNe with an initial rough luminosity distribution peaked at
Mr=-17.61±0.72, and where 36% are apparently brighter than the
theoretically predicted maximum brightness of Mr=-17.8. When we
further cull this sample to ensure that the SNe are normal Type Ibc
with good LC data within the Hubble flow, the sample of 94 objects has
Mr=-17.64±0.54. A main uncertainty in absolute magnitude
determinations for SNe is the host galaxy extinction correction, but
the reddened objects only get more luminous after corrections. If we
simply exclude objects with red, unusual or uncertain colors, we are
left with 14 objects at Mr=-17.90±0.73, whereof a handful are most
certainly brighter than the suggested theoretical limit. The main
result of this study is thus that normal SNe Ibc do indeed reach
luminosities above 1042.6erg/s, apparently in conflict with existing
explosion models.
Description:
All photometric observations in this paper were conducted with the
Palomar Schmidt 48-inch (P48) Samuel Oschin telescope as part of the
ZTF survey, using the ZTF camera (Dekany et al., 2020PASP..132c8001D 2020PASP..132c8001D).
The light curves from the P48 come from the ZTF pipeline (Masci et
al., 2019PASP..131a8003M 2019PASP..131a8003M). All magnitudes are reported in the AB
system.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 136 14 Final sample of supernovae and their host galaxies
phot/* . 14 Individual light curves
listsp.dat 67 8 List of individual spectra
sp/* . 13 Invividual spectra
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- ZTFID ZTF name (ZTFYYaaaaaaa)
14- 24 A11 --- IAUID IAU name (SN YYYYaaaa)
26- 30 A5 --- Type SN type
32- 33 I2 h RAh SN right ascension (J2000)
35- 36 I2 min RAm SN right ascension (J2000)
38- 42 F5.2 s RAs SN right ascension (J2000)
44 A1 --- DE- SN declination sign (J2000)
45- 46 I2 deg DEd SN declination (J2000)
48- 49 I2 arcmin DEm SN declination (J2000)
51- 54 F4.1 arcsec DEs SN declination (J2000)
56- 60 F5.3 --- z Redshift
62- 65 F4.2 mag AV MW extinction
67- 68 I2 h RAHh Host right ascension (J2000)
70- 71 I2 min RAHm Host right ascension (J2000)
73- 77 F5.2 s RAHs Host right ascension (J2000)
79 A1 --- DEH- Host declination sign (J2000)
80- 81 I2 deg DEHd Host declination (J2000)
83- 84 I2 arcmin DEHm Host declination (J2000)
86- 89 F4.1 arcsec DEHs Host declination (J2000)
91- 96 F6.2 mag gMAG Host absolute g magnitude (1)
98-101 F4.2 mag E_gMAG Error on host absolute g magnitude, upper value
103-106 F4.2 mag e_gMAG Error on host absolute g magnitude, lower value
108 A1 --- Note [*] Individual note (2)
110-136 A27 --- FileName Name of the file with photometric data in
subdirectory phot
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Note (1): The host galaxy photometry was measured from SDSS and PanSTARRS images
using LAMBDAR (Wright et al., 2016MNRAS.460..765W 2016MNRAS.460..765W) and translated to absolute
magnitudes by modeling the host-galaxy spectral energy distributions with
Prospector (Johnson et al., 2021ApJS..254...22J 2021ApJS..254...22J) following Schulze et al.
(2021ApJS..255...29S 2021ApJS..255...29S). The absolute magnitudes are corrected for MW extinction
but not for host attenuation.
Note (2): About 2" from the center of the host galaxy of SN 2019ieh is another
object. It is uncertain whether this is a star-forming region or a separate
galaxy.
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Byte-by-byte Description of file: phot/*
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Bytes Format Units Label Explanations
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1- 10 F10.2 d JD Julian Date
12 A1 --- Filter [gr] Filter name
14- 19 F6.2 d Phase Rest Frame Phase
21- 25 F5.2 mag mag Apparent magnitude
27- 31 F5.2 mag e_mag Error of magnitude
33- 37 F5.2 mag limmag Limiting magnitude
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Byte-by-byte Description of file: listsp.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name SN name
13- 42 A30 --- Sp1 FileName1 of the first spectrum,
in subdirectory sp
44- 67 A24 --- Sp2 FileName2 of the first spectrum,
in subdirectory sp
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 6 F6.1 0.1nm lambda Wavelength
8- 30 E23.17 10mW/m2/nm Flux Flux (erg/cm2/s/Å)
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Acknowledgements:
Sheng Yang, sheng.yang(at)astro.su.se
(End) Patricia Vannier [CDS] 29-Oct-2021