J/MNRAS/483/5045 R-band light-curve properties of SN Ia (Papadogiannakis+, 2019)
R-band light-curve properties of Type Ia supernovae from the (intermediate)
Palomar Transient Factory.
Papadogiannakis S., Goobar A., Amanullah R., Bulla M., Dhawan S., Doran G.,
Feindt U., Ferretti R., Hangard L., Howell D.A., Johansson J.,
Kasliwal M.M., Laher R., Masci F., Nyholm A., Ofek E., Sollerman J., Yan L.
<Mon. Not. R. Astron. Soc., 483, 5045-5076 (2019)>
=2019MNRAS.483.5045P 2019MNRAS.483.5045P (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry ; Optical ; Redshifts
Keywords: supernovae: general - cosmology: observations
Abstract:
We present the best 265 sampled R-band light curves of
spectroscopically identified Type Ia supernovae (SNe) from the Palomar
Transient Factory (PTF; 2009-2012) survey and the intermediate Palomar
Transient Factory (iPTF; 2013-2017). A model-independent light-curve
template is built from our data-set with the purpose to investigate
average properties and diversity in our sample. We searched for
multiple populations in the light-curve properties using machine
learning tools. We also utilized the long history of our light curves,
up to 4000 days, to exclude any significant pre- or post- supernova
flares. From the shapes of light curves we found the average rise time
in the R band to be 16.8+0.5-0.6days. Although PTF/iPTF were
single-band surveys, by modelling the residuals of the SNe in the
Hubble-Lemaitre diagram, we estimate the average colour excess of our
sample to be <E(B-V)≳0.05(2)mag and thus the mean corrected peak
brightness to be MR=-19.02±0.02+5log(H0[km/s/Mpc]/70)mag with
only weak dependence on light-curve shape. The intrinsic scatter is
found to be σR=0.186±0.033mag for the redshift range
0.05<z<0.1, without colour corrections of individual SNe. Our analysis
shows that Malmquist bias becomes very significant at z=0.13. A
similar limitation is expected for the ongoing Zwicky Transient
Facility (ZTF) survey using the same telescope, but new camera
expressly designed for ZTF.
Description:
PTF and iPTF surveyed the sky regularly to discover new transients
with an unprecedented large field of view. The survey was conducted in
a single filter at a time, mostly in the Mould R band (wavelength
range 5800-7300Å), but data in g band (wavelength range
3900-5600Å) were also collected during some periods. Narrow
Hα filters at several recession velocities were used during the
2-5 days closest to the full moon each month. The magnitude limit of
the survey was 20.5 and 21 magnitudes for R and g band, respectively,
in the PTF system. In this paper, we focus on the R-band observations.
All photometric data used in this paper are in the Mould R band (see
Law et al. 2009PASP..121.1395L 2009PASP..121.1395L), corrected for quantum efficiency of
the instrument. The PTF image processing is described in Laher et al.
(2014PASP..126..674L 2014PASP..126..674L). We used the PTF-IPAC forced photometry pipeline
by Masci et al. (2017PASP..129a4002M 2017PASP..129a4002M), to produce the light curves.
In this paper, we examine the statistical properties of 265 out of
2059 spectroscopically confirmed type Ia supernovae from PTF and iPTF
(from 2009 to 2017), selected due to their well-sampled R-band light
curves. We do not exclude any SNe based on their spectroscopic
sub-classification. Due to the observing strategies in 2015 and 2017,
no SN Ia was included from these years.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablee1.dat 108 207 Best-fit values for each supernova with their
respective asymmetric errors
tablee2.dat 69 244 Fit values and redshifts of the SNe in our
sample
tablee3.dat 74 263 The SALT2 fit parameters for our SNe sample
tablee4.dat 20 96 The Gaussian processes template binned in bins
of 1 day
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Byte-by-byte Description of file: tablee1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Supernova name (PTF YYaaaa)
12- 18 F7.3 d t0 Explosion time (1)
20- 25 F6.3 d E_t0 Upper error on t0 (1)
27- 32 F6.3 d e_t0 Lower error on t0 (1)
34- 39 F6.3 --- A Normalizing factor (1)
41- 46 F6.3 --- E_A Upper error on A (1)
48- 53 F6.3 --- e_A Lower error on A (1)
55- 60 F6.3 --- alphad Free parameter determining the shape of the
light curve αd (1)
62- 66 F5.3 --- E_alphad Upper error on alphad (1)
68- 72 F5.3 --- e_alphad Lower error on alphad (1)
74- 78 F5.3 --- s Smoothing parameter (1)
80- 84 F5.3 --- E_s Upper error on s (1)
86- 90 F5.3 --- e_s Lower error on s (1)
92- 96 F5.3 --- alphar Free parameter determining the shape of the
light curve αr (1)
98-102 F5.3 --- E_alphar Upper error on alphar (1)
104-108 F5.3 --- e_alphar Lower error on alphar (1)
--------------------------------------------------------------------------------
Note (1): Best-fitting parameters from the light curve fit:
L=A[(t-t0)/tb]alphar[1+((t-t0)/tb)s.alphad]-2/s where the break
time is fixed to tb=20.4days
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablee2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Supernova name (PTF YYaaaa)
12- 19 F8.6 --- z Redshift
21- 30 F10.6 deg RAdeg Right ascension (J2000)
32- 40 F9.6 deg DEdeg Declination (J2000)
42- 46 F5.2 mag HR ? Hubble-Lemaitre residual
48- 52 F5.2 mag Rmag ? Peak R-band magnitude
54- 58 F5.3 mag e_Rmag ? Error on Rmag
60- 63 F4.2 --- Stretch ? Stretch factor (1)
65- 69 F5.3 --- e_Stretch ? Error on Stretch
--------------------------------------------------------------------------------
Note (1): Stretch is defined to be a multiplicative factor that measures the
width of the light curves, thus Stretch<1 implies a narrow shape,
Stretch>1 a broad shape, and Stretch=1 a shape that exactly matches
that of the template similar to what was done in Perlmutter et al.
(1997ApJ...483..565P 1997ApJ...483..565P).
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Byte-by-byte Description of file: tablee3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Supernova name (PTF YYaaaa)
12- 19 F8.6 --- zcmb Cosmic Microwave Background frame redshift
21- 30 F10.2 d t0 SALT2 Observer-frame time corresponding to the
source's phase=0
32- 38 F7.2 d e_t0 Error on t0
40- 43 F4.2 --- x0 SALT2 light-curve amplitude
45- 48 F4.2 --- e_x0 Error on x0
50- 54 F5.2 --- x1 SALT2 light-curve width
56- 59 F4.2 --- e_x1 Error on x1
61- 67 F7.2 --- Chi2 Reduced chi-squared of the SALT2 fit
69- 74 F6.2 --- dof Number of degrees of freedom allowed in SALT2
fitting
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Byte-by-byte Description of file: tablee4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.2 d Time Time binned in bins of 1 day
8- 13 F6.4 --- F/Fpeak Normalized flux
15- 20 F6.4 --- e_F/Fpeak Error on F/Fpeak
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 03-Aug-2022