J/ApJS/220/20 Si and Ca high-velocity features in SNe Ia (Zhao+, 2015)
The silicon and calcium high-velocity features in Type Ia supernovae from
early to maximum phases.
Zhao X., Wang X., Maeda K., Sai H., Zhang T., Zhang J., Huang F., Rui L.,
Zhou Q., Mo J.
<Astrophys. J. Suppl. Ser., 220, 20 (2015)>
=2015ApJS..220...20Z 2015ApJS..220...20Z (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Spectroscopy ; Equivalent widths
Keywords: methods: data analysis; supernovae: general; techniques: spectroscopic
Abstract:
The high-velocity features (HVFs) in optical spectra of type Ia
supernovae (SNe Ia) are examined with a large sample including very
early-time spectra (e.g., t←7days). Multiple Gaussian fits are
applied to examine the HVFs and their evolutions, using constraints on
expansion velocities for the same species (i.e., SiII5972 and
SiII6355). We find that strong HVFs tend to appear in SNe Ia with
smaller decline rates (e.g., Δm15(B)≲1.4mag), clarifying that
the finding by Childress et al. (2014MNRAS.437..338C 2014MNRAS.437..338C) for the Ca-HVFs
in near-maximum-light spectra applies both to the Si-HVFs and Ca-HVFs
in the earlier phase. The Si-HVFs seem to be more common in rapidly
expanding SNe Ia, which is different from the earlier result that
Ca-HVFs are associated with SNe Ia that have slower SiII6355
velocities at maximum light (i.e., VSimax). Moreover, SNe Ia with
both stronger HVFs at early phases and larger VSimax are found to
have noticeably redder B-V colors and to occur preferentially in the
inner regions of their host galaxies, while those with stronger HVFs
but smaller VSimax show opposite tendencies, suggesting that these
two subclasses have different explosion environments and their HVFs
may have different origins. We further examine the relationships
between the absorption features of SiII6355 and CaII IR lines, and
find that their photospheric components are well correlated in
velocity and strength but that the corresponding HVFs show larger
scatter. These results cannot be explained with ionization and/or
thermal processes alone, and different mechanisms are required for the
creation of HVF-forming regions in SNe Ia.
Description:
The spectral data used in our analysis are primarily taken from the
CfA supernova program (Matheson et al. 2008, J/AJ/135/1598; Blondin et
al. 2012, J/AJ/143/126), the Berkeley supernova program (Silverman et
al. 2012,J/MNRAS/425/1789; 2012, J/MNRAS/425/1819), the Carnegie
supernova project (CSP; Folatelli et al. 2013, J/ApJ/773/53), and our
own database (L. Rui et al. 2015, in preparation).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 107 204 Photometric and spectroscopic parameters of type Ia
supernovae
table3.dat 47 306 Fit results of the SiII absorption features
λ6355 and λ5972 from Sample A (108 SNe)
table4.dat 38 98 Fit results of the CaII IR triplet of Sample B (47 SNe)
table5.dat 47 149 Fit results of the SiII 6355 and CaII IR absorptions
from Sample C (126 SNe)
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
J/A+A/578/A9 : Optical and NIR spectra of SN iPTF13ebh (Hsiao+, 2015)
J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)
J/AJ/148/1 : Optical and ultraviolet photometry of SN 2012fr (Zhang+, 2014)
J/ApJ/773/53 : Type Ia SNe spectroscopy by the CSP (Folatelli+, 2013)
J/ApJ/770/107 : Host galaxies of SNIa from SNfactory (Childress+, 2013)
J/other/Sci/340.170 : Classifications of 188 SNe Ia (Wang+, 2013)
J/MNRAS/425/1819 : Berkeley supernova Ia program. II. (Silverman+, 2012)
J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)
J/ApJS/200/12 : CfA4: light curves for 94 type Ia SNe (Hicken+, 2012)
J/AJ/143/126 : Spectroscopy of 462 nearby Type Ia supernovae (Blondin+, 2012)
J/ApJS/199/26 : The 2MASS Redshift Survey (2MRS) (Huchra+, 2012)
J/ApJ/749/18 : Swift/UVOT observations of 12 nearby SN-Ia (Brown+, 2012)
J/ApJ/745/74 : Pre-maximum spectra of type Ia SNe (Folatelli+, 2012)
J/MNRAS/410/1262 : Supernova Legacy Survey. Type Ia supernovae (Walker+, 2011)
J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
J/A+A/529/L4 : Reddening law of type Ia supernovae (Chotard+, 2011)
J/ApJS/190/418 : Light curves for 165 SNe (Ganeshalingam+, 2010)
J/AJ/139/519 : Carnegie supernova project. SNe Ia (Contreras+, 2010)
J/PASP/122/1 : BVRI light curves of SN 2007gi (Zhang+, 2010)
J/ApJ/700/331 : Light curves of type Ia supernovae (CfA3) (Hicken+, 2009)
J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)
J/AJ/135/1598 : Optical spectroscopy of type Ia supernovae (Matheson+, 2008)
J/A+A/477/717 : Spectroscopy of Type Ia supernovae (Bronder+, 2008)
J/A+A/471/527 : Spectroscopy of SN 2005cf (Garavini+, 2007)
J/AJ/131/527 : UBVRI light curves of 44 type Ia supernovae (Jha+, 2006)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- SN IAU SN Ia designation
8- 13 A6 --- SubCl Wang et al. subclassification
(2009ApJ...699L.139W 2009ApJ...699L.139W) (1)
15- 18 F4.2 mag m15B [0.6/2]? Light-curve decline rate in
B band (1993ApJ...413L.105P 1993ApJ...413L.105P)
20- 23 F4.2 mag e_m15B [0.01/0.7]? m15B uncertainty
25- 29 F5.2 mag B-V ? Peak B-V Color corrected for the
Milky Way reddening
31- 34 F4.2 mag e_B-V ? Uncertainty in peak B-V Color
36- 40 I5 km/s Vcmb [64/24600]? Recession velocity in 3K CMB
ref frame
42- 46 A5 --- MType Morphological Hubble type of host galaxy
48- 52 F5.2 --- DType [-5/10]? Digital Hubble type of host galaxy
54- 57 F4.2 --- Rsn [0.02/2.5]? Projected galactocentric
distance of the SN in its host galaxy, in
units of the galaxy radius (Rsn/Rgal)
59- 64 F6.2 mag KMAG [-26.3/-20.4]? Galaxy absolute K magnitude
66- 69 F4.2 mag e_KMAG [0.07/1]? uncertainty on KMAG
71- 76 A6 --- HVF Subclassifications of high velocity
features, based on Rhvf from SiII 6355
absorption ("IB", "strong" or "weak")
78- 81 F4.2 --- Rf(Si6355)e [0/1]? Rhvf from SiII 6355 absorption;
at early phases -- t~-8d (2)
83- 87 F5.2 --- Rf(CaIR)e [0.1/12.5]? Rhvf from CaII IR triplet;
at early phases, t~-8d (2)
89- 92 F4.2 --- Rf(CaIR)m [0/2.1]? Rhvf from CaII IR triplet;
near maximum light (2)
94- 98 A5 --- Prog SN Program References (3)
100-107 A8 --- Ref Individual References (4)
--------------------------------------------------------------------------------
Note (1): SN type as follows:
N = "Normal" group which consists of normal SNe Ia populating a narrow strip
in the SiII velocity distribution, with an average expansion velocity
<ν≥10600±400km/s near B maximum;
HV = the other group which consists of objects with higher velocities,
ν≳11800km/s.
Note (2): Rhvf, the ratio of the pseudo-equivalent width of the HVF absorption
feature to the pseudo-equivalent width of the photospheric component,
as defined by Childress et al. (2014MNRAS.437..338C 2014MNRAS.437..338C).
Note (3): Supernova Program References as follows:
A = CfA supernova program (2008AJ....135.1598M 2008AJ....135.1598M, 2012AJ....143..126B 2012AJ....143..126B);
B = Berkeley Supernova Program (2012MNRAS.425.1789S 2012MNRAS.425.1789S, 2012MNRAS.425.1819S 2012MNRAS.425.1819S);
C = Carnegie Supernova Project (2013ApJ...773...53F 2013ApJ...773...53F);
D = Tsinghua Supernova Program
Note (4): Individual references as follows:
1 = 1989A&A...220...83B 1989A&A...220...83B;
2 = 1990A&A...237...79B 1990A&A...237...79B;
3 = 2015MNRAS.451.1973S 2015MNRAS.451.1973S;
4 = 1998AJ....115..234L 1998AJ....115..234L;
5 = 2006MNRAS.370..299H 2006MNRAS.370..299H;
6 = 1996MNRAS.278..111P 1996MNRAS.278..111P;
7 = 1999AJ....117..707R 1999AJ....117..707R;
8 = 2006AJ....131..527J 2006AJ....131..527J;
9 = 2010ApJS..190..418G 2010ApJS..190..418G;
10 = 2002AJ....124.2100S 2002AJ....124.2100S;
11 = 2003ApJ...595..779V 2003ApJ...595..779V;
12 = 2009ApJ...700.1097H 2009ApJ...700.1097H;
13 = 2003AJ....125..166K 2003AJ....125..166K;
14 = 2005A&A...443..649M 2005A&A...443..649M;
15 = 2010AJ....139..519C 2010AJ....139..519C;
16 = 2011AJ....142..156S 2011AJ....142..156S;
17 = 2007ApJ...669L..17H 2007ApJ...669L..17H;
18 = 2012ApJS..200...12H 2012ApJS..200...12H;
19 = 2010PASP..122....1Z 2010PASP..122....1Z;
20 = This article;
21 = 2012ApJ...756L...7S 2012ApJ...756L...7S;
22 = 2008ApJ...675..626W 2008ApJ...675..626W
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- SN IAU SN Ia designation
8- 12 F5.1 d Phase Days since the B-band maximum light
14- 18 I5 km/s VSi6355 [9153/17110] Photospheric velocity of SiII6355
absorption
20- 22 I3 0.1nm pEWSi6355 [15/210] Pseudo-Equivalent width of the
photospheric component of SiII6355 absorption
24- 28 I5 km/s VfSi6355 [16000/24000] Velocity of the high-velocity
feature of SiII 6355 absorption
30- 32 I3 0.1nm pEWfSi6355 [0/125] Pseudo-Equivalent width of the
high-velocity feature of SiII 6355
34- 37 F4.2 --- Rf(Si6355) [0/5.3] Ratio of pEWf to pEW
39- 43 I5 km/s VSi5972 [9500/16915] Photospheric velocity of SiII5972
45- 47 I3 0.1nm pEWSi5972 [0/66] Pseudo-Equivalent width of photospheric
component of SiII 5972
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- SN IAU SN Ia designation
8- 12 F5.1 d Phase Days since the B-band maximum light
14- 18 I5 km/s VCaIR [9756/16010] Velocity of the photospheric
components of CaII IR triplet
20- 22 I3 0.1nm pEWCaIR [5/186] Pseudo-Equivalent width of the
photospheric components of CaII IR triplet
24- 28 I5 km/s VfCaIR [19503/27299] Velocity of the high-velocity
feature components of CaII IR triplet
30- 32 I3 0.1nm pEWfCaIR [8/331] Pseudo-Equivalent width of the
high-velocity feature components of
CaII IR triplet
34- 38 F5.2 --- Rf(CaIR) [0.2/17] Ratio of pEWf to pEW
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- SN IAU SN Ia designation
8- 11 F4.1 d Phase Days since the B-band maximum light
13- 17 I5 km/s VSi6355 [8500/15059] Velocity of the photospheric
components of SiII 6355 absorption
19- 21 I3 0.1nm pEWSi6355 [50/190] Pseudo-Equivalent width of the
photospheric component of SiII 6355 absorption
23- 27 I5 km/s VCaIR [7799/15418] Velocity of the photospheric
components of CaII IR triplet
29- 31 I3 0.1nm pEWCaIR [33/230] Pseudo-Equivalent width of the
photospheric components of CaII IR triplet
33- 37 I5 km/s VfCaIR [15806/34116] Velocity of the high-velocity
feature components of CaII IR triplet
39- 41 I3 0.1nm pEWfCaIR [0/196] Pseudo-Equivalent width of the
high-velocity feature components of CaII
IR triplet
43- 47 F5.2 --- Rf(CaIR) [0/2.1] Ratio of pEWhvf to pEWpho
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Acknowledgements:
Xulin Zhao [Tsinghua University, Beijing; Kyoto University, Kyoto] for
the additional SN2006lf information in table 1.
History:
23-Sept-2015: Tables 1, 3, 4, 5 published in machine-readable version
* 08-Dec-2015: First publication into the VizieR FTP service
* 10-Dec-2015: Table1 completed with information of SN2006lf;
see the acknowledgements section above.
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 09-Nov-2015