J/A+A/529/L4 Reddening law of type Ia supernovae (Chotard+, 2011)
The reddening law of type Ia supernovae: separating intrinsic variability
from dust using equivalent widths.
Chotard N., Gangler E., Aldering G., Antilogus P., Aragon C., Bailey S.,
Baltay C., Bongard S., Buton C., Canto A., Childress M., Copin Y.,
Fakhouri H.K., Hsiao E.Y., Kerschhaggl M., Kowalski M., Loken S.,
Nugent P., Paech K., Pain R., Pecontal E., Pereira R., Perlmutter S.,
Rabinowitz D., Runge K., Scalzo R., Smadja G., Tao C., Thomas R.C.,
Weaver B.A., Wu C., (The Nearby Supernova Factory)
<Astron. Astrophys., 529, L4-4 (2011)>
=2011A&A...529L...4C 2011A&A...529L...4C
ADC_Keywords: Supernovae ; Photometry ; Equivalent widths
Keywords: supernovae: general - dust, extinction - cosmology: observations
Abstract:
We employ 76 type Ia supernovae (SNe Ia) with optical
spectrophotometry within 2.5 days of B-band maximum light obtained by
the Nearby Supernova Factory to derive the impact of Si and Ca
features on the supernovae intrinsic luminosity and determine a dust
reddening law. We use the equivalent width of SiII λ4131 in
place of the light curve stretch to account for first-order intrinsic
luminosity variability. The resulting empirical spectral reddening law
exhibits strong features that are associated with CaII and SiII
λ6355. After applying a correction based on the CaII H&K
equivalent width we find a reddening law consistent with a Cardelli
extinction law. Using the same input data, we compare this result to
synthetic rest-frame UBVRI-like photometry to mimic literature
observations.
Description:
This analysis uses flux calibrated spectra of 76 SNe Ia obtained by
the SNfactory collaboration with its SNIFS instrument on the
University of Hawaii 2.2-m telescope on Mauna Kea.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 142 76 Supernovae used in this work
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Supernova name
17 A1 --- Disc Discovery (1)
19- 24 F6.4 --- zcmb Redshift (2)
26- 31 F6.3 mag DMU Synthetic U magnitude after phase correction
33- 37 F5.3 mag e_DMU rms uncertainty on DMU
39- 44 F6.3 mag DMB Synthetic B magnitude after phase correction
46- 50 F5.3 mag e_DMB rms uncertainty on DMB
52- 57 F6.3 mag DMV Synthetic V magnitude after phase correction
59- 63 F5.3 mag e_DMV rms uncertainty on DMV
65- 70 F6.3 mag DMR Synthetic R magnitude after phase correction
72- 76 F5.3 mag e_DMR rms uncertainty on DMR
78- 83 F6.3 mag DMI Synthetic I magnitude after phase correction
85- 89 F5.3 mag e_DMI rms uncertainty on DMI
91- 95 F5.2 --- x1 SALT2 fit parameter x1
97-100 F4.2 --- e_x1 rms uncertainty on x1
102-107 F6.3 --- c SALT2 fit parameter c
109-113 F5.3 --- e_c rms uncertainty on c
115-118 F4.1 0.1nm W(Si) SiII λ4131 equivalent width
120-122 F3.1 0.1nm e_W(Si) rms uncertainty on W(Si)
124-128 F5.1 0.1nm W(Ca) Ca II H&K equivalent width
130-133 F4.1 0.1nm e_W(Ca) rms uncertainty on W(Ca)
135-138 F4.1 d Phase Phase (days after maximum)
140-142 F3.1 d e_Phase rms uncertainty on Phase
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Note (1): Discovery code as follows:
a = Boles, Armstrong
b = LOSS
c = Sloan Digital Sky Survey II
d = Prasad, Li (LOSS)
e = Orff, Newton
f = Parisky, Li (LOSS)
g = Monard
h = Quimby et al.
i = PTF. Discovery attribution was obtained from
http://www.cfa.harvard.edu/iau/lists/Supernovae.html and the CBAT
Note (2): Redshifts are taken from Cooke et al. (2011ApJ...727L..35C 2011ApJ...727L..35C)
and Childress et al. (in prep.).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 19-Aug-2011