J/ApJ/788/154 Palomar Transient Factory SNe IIn photometry (Ofek+, 2014)
Interaction-powered supernovae: rise-time versus peak-luminosity correlation
and the shock-breakout velocity.
Ofek E.O., Arcavi I., Tal D., Sullivan M., Gal-Yam A., Kulkarni S.R.,
Nugent P.E., Ben-Ami S., Bersier D., Cao Y., Cenko S.B., De Cia A.,
Filippenko A.V., Fransson C., Kasliwal M.M., Laher R., Surace J.,
Quimby R., Yaron O.
<Astrophys. J., 788, 154 (2014)>
=2014ApJ...788..154O 2014ApJ...788..154O (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Redshifts ; Extinction ; Photometry, RI ;
Photometry, SDSS
Keywords: stars: massive - stars: mass-loss - supernovae: general
Abstract:
Interaction of supernova (SN) ejecta with the optically thick
circumstellar medium (CSM) of a progenitor star can result in a
bright, long-lived shock-breakout event. Candidates for such SNe
include Type IIn and superluminous SNe. If some of these SNe are
powered by interaction, then there should be a specific relation
between their peak luminosity, bolometric light-curve rise time, and
shock-breakout velocity. Given that the shock velocity during shock
breakout is not measured, we expect a correlation, with a significant
spread, between the rise time and the peak luminosity of these SNe.
Here, we present a sample of 15 SNe IIn for which we have good
constraints on their rise time and peak luminosity from observations
obtained using the Palomar Transient Factory. We report on a possible
correlation between the R-band rise time and peak luminosity of these
SNe, with a false-alarm probability of 3%. Assuming that these SNe are
powered by interaction, combining these observables and theory allows
us to deduce lower limits on the shock-breakout velocity. The lower
limits on the shock velocity we find are consistent with what is
expected for SNe (i.e., ∼104 km/s). This supports the suggestion
that the early-time light curves of SNe IIn are caused by shock
breakout in a dense CSM. We note that such a correlation can arise
from other physical mechanisms. Performing such a test on other
classes of SNe (e.g., superluminous SNe) can be used to rule out the
interaction model for a class of events.
Description:
The Palomar Transient Factory (PTF; Law et al. 2009PASP..121.1395L 2009PASP..121.1395L;
Rau et al. 2009PASP..121.1334R 2009PASP..121.1334R) and its extension the intermediate PTF
(iPTF) found over 2200 spectroscopically confirmed SNe. We selected 19
SNe IIn for which PTF/iPTF has good coverage of the light-curve rise
and peak; they are listed in Table 1. Optical spectra were obtained
with a variety of telescopes and instruments, including the Double
Spectrograph (Oke & Gunn 1982PASP...94..586O 1982PASP...94..586O) at the Palomar 5 m Hale
telescope, the Kast spectrograph (Miller & Stone 1993, Lick Observatory
Technical Report 66 (Santa Cruz, CA: Lick Observatory)) at the Lick 3 m
Shane telescope, the Low Resolution Imaging Spectrometer (Oke et al.
1995PASP..107..375O 1995PASP..107..375O) on the Keck-1 10 m telescope, and the Deep
Extragalactic Imaging Multi-Object Spectrograph (Faber et al.
2003SPIE.4841.1657F 2003SPIE.4841.1657F) on the Keck-2 10 m telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 106 19 Supernovae Sample
table2.dat 39 1006 Supernovae Photometry
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See also:
II/313 : Palomar Transient Factory (PTF) photometric catalog 1.0
(Ofek+, 2012)
J/ApJ/789/104 : SNe IIn observations and properties (Ofek+, 2014)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- PTF SN identifier (PTF YYaaa; iPTF YYaaa in Simbad)
11 A1 --- n_PTF [n] Note on PTF (1)
13- 20 F8.4 deg RAdeg Right Ascension in decimal degrees (J2000)
22- 29 F8.4 deg DEdeg Declination in decimal degrees (J2000)
31- 35 F5.3 --- z Redshift
37- 41 F5.2 mag MOD Distance modulus of the SN host galaxy
43- 47 F5.3 mag E(B-V) Galactic extinction in the SN direction
49- 55 F7.1 d t0 MJD of the fitted zero flux
57- 63 F7.1 d tmax MJD of the R-band light-curve peak
65- 70 E6.2 10-7W Lmax Peak luminosity corresponding to tmax
72- 77 E6.2 10-7W L0 Luminosity extrapolated to a time of 1 s (2)
79- 82 F4.1 d te Exponential rise time of the early-time
light curve
84- 87 F4.1 d e_te ? Uncertainty in te
89- 93 F5.1 --- chi2 The χ2 value
94 A1 --- --- [/]
95- 96 I2 --- DOF [2/58] Degree of freedom
98-101 I4 km/s vbo Lower limit on the shock velocity (3)
103-106 F4.1 [g/cm] log10K Log of the mass-loading parameter (4)
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Note (1): Note as follows:
n = SN has relative error in te larger than 50% and was excluded from our
correlation analysis.
Note (2): L0=Lmax(t/tbo)-α, where the time is measured in seconds
(e.g., Equation (2)).
Note (3): Deduced from Equation (1) and assuming ε=0.3, w=2, and m=10;
κ=0.34 cm2/g.
Note (4): K=M/(4πνw) is calculated assuming a wind profile with w=2.
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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- 9 A9 --- PTF SN identifier (PTF YYaaa; iPTF YYaaa in Simbad)
12- 14 A3 --- Tel Telescope (1)
16 A1 --- Filter [grRi] Filter
18- 26 F9.3 d MJD Modified Julian Date
28- 33 F6.3 mag mag The PTF magnitude in Filter
35- 39 F5.3 mag e_mag Error in mag
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Note (1): Telescope as follows:
PTF = Palomar Transient Factory;
P60 = Palomar 60-inch telescope;
LT = Liverpool 2-m telescope.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 17-Jul-2017