J/MNRAS/446/3895 The rising light curves of Type Ia supernovae (Firth+, 2015)
The rising light curves of Type Ia supernovae.
Firth R.E., Sullivan M., Gal-Yam A., Howell D.A., Maguire K., Nugent P.,
Piro A.L., Baltay C., Feindt U., Hadjiyksta E., McKinnon R., Ofek E.,
Rabinowitz D., Walker E.S.
<Mon. Not. R. Astron. Soc., 446, 3895-3910 (2015)>
=2015MNRAS.446.3895F 2015MNRAS.446.3895F (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry ; Redshifts
Keywords: supernovae: general
Abstract:
We present an analysis of the early, rising light curves of 18
Type Ia supernovae (SNe Ia) discovered by the Palomar Transient
Factory and the La Silla-QUEST variability survey. We fit these early
data flux using a simple power law (f(t)=αxtn) to determine the
time of first light (t0), and hence the rise time (trise) from
first light to peak luminosity, and the exponent of the power-law rise (n).
We find a mean uncorrected rise time of 18.98±0.54 d, with
individual supernova (SN) rise times ranging from 15.98 to 24.7 d. The
exponent n shows significant departures from the simple `fireball
model' of n=2 (or f(t)∝t2) usually assumed in the literature.
With a mean value of n=2.44±0.13, our data also show significant
diversity from event to event. This deviation has implications for the
distribution of 56Ni throughout the SN ejecta, with a higher index
suggesting a lesser degree of 56Ni mixing. The range of n found also
confirms that the 56Ni distribution is not standard throughout the
population of SNe Ia, in agreement with earlier work measuring such
abundances through spectral modelling. We also show that the duration
of the very early light curve, before the luminosity has reached half
of its maximal value, does not correlate with the light-curve shape or
stretch used to standardize SNe Ia in cosmological applications. This
has implications for the cosmological fitting of SN Ia light curves.
Description:
Our data come from two local, rolling SN surveys. The first is the PTF
(Law et al. 2009PASP..121.1395L 2009PASP..121.1395L; Rau et al. 2009PASP..121.1334R 2009PASP..121.1334R),
a wide-field survey using the CFH12k camera mounted on the 48 inch
Samuel Oschin telescope at Palomar Observatory (the P48 telescope).
The survey operated primarily in an R-band filter (hereafter RP48),
with occasional runs in a g filter (gP48) around new moon. The second
survey is the LSQ (Baltay et al. 2013PASP..125..683B 2013PASP..125..683B), a Southern
Hemisphere variability survey using the 10 deg2 QUEST instrument
(Baltay et al. 2007PASP..119.1278B 2007PASP..119.1278B) on the 1.0 m European Southern
Observatory Schmidt telescope at La Silla, Chile. LSQ operates with a
cadence of between 2 h and 2 d, using a broad gr filter (hereafter grLSQ).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sn.dat 40 18 List of SNe Ia in this catalog
table2.dat 66 1170 Full SNe Ia sample data
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
II/313 : Palomar Transient Factory (PTF) photometric catalog 1.0
(Ofek+, 2012)
J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)
J/ApJS/219/13 : SNe Ia light curves for the LSQ-CSP sample (Walker+, 2015)
Byte-by-byte Description of file: sn.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- SN SN identifier (PTF YYaaaa, LSQ YYaaa)
11- 12 I2 h RAh Simbad Hour of Right Ascension (J2000)
14- 15 I2 min RAm Simbad Minute of Right Ascension (J2000)
17- 21 F5.2 s RAs Simbad Second of Right Ascension (J2000)
23 A1 --- DE- Simbad Sign of the Declination (J2000)
24- 25 I2 deg DEd Simbad Degree of Declination (J2000)
27- 28 I2 arcmin DEm Simbad Arcminute of Declination (J2000)
30- 33 F4.1 arcsec DEs Simbad Arcsecond of Declination (J2000)
35- 40 A6 --- Filter Filter used for the observation
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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 --- SN SN identifier (PTF YYaaaa, LSQ YYaaa)
11- 16 A6 --- Filter Filter used for the observation
18- 26 F9.3 d MJD Modified Julian Date of observation
28- 36 F9.1 ct Cts Observed counts
38- 44 F7.1 ct e_Cts Uncertainty in Cts
46- 49 F4.1 mag ZPmag [27.0] Zero-point AB magnitude
51- 59 F9.7 --- z Redshift
61- 66 F6.4 --- e_z Uncertainty in z
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 07-Nov-2017