J/ApJ/827/90 Spectroscopy of SNe Ib, IIb and Ic (Liu+, 2016)
Analyzing the largest spectroscopic data set of stripped supernovae to improve
their identifications and constrain their progenitors.
Liu Y.-Q., Modjaz M., Bianco F.B., Graur O.
<Astrophys. J., 827, 90-90 (2016)>
=2016ApJ...827...90L 2016ApJ...827...90L (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Spectroscopy ; Equivalent widths
Keywords: methods: data analysis; supernovae: general;
supernovae: individual: SNe 1993J, 2005bf, 2005E, 2011dh
Abstract:
Using the largest spectroscopic data set of stripped-envelope
core-collapse supernovae (stripped SNe), we present a systematic
investigation of spectral properties of Type IIb SNe (SNe IIb), Type
Ib SNe (SNe Ib), and Type Ic SNe (SNe Ic). Prior studies have been
based on individual objects or small samples. Here, we analyze 242
spectra of 14 SNe IIb, 262 spectra of 21 SNe Ib, and 207 spectra of 17
SNe Ic based on the stripped SN data set of Modjaz et al.
(2016ApJ...832..108M 2016ApJ...832..108M) and other published spectra of individual SNe.
Each SN in our sample has a secure spectroscopic ID, a date of V-band
maximum light, and most have multiple spectra at different phases. We
analyze these spectra as a function of subtype and phase in order to
improve the SN identification scheme and constrain the progenitors of
different kinds of stripped SNe. By comparing spectra of SNe IIb with
those of SNe Ib, we find that the strength of Hα can be used to
quantitatively differentiate between these two subtypes at all epochs.
Moreover, we find a continuum in observational properties between SNe
IIb and Ib. We address the question of hidden He in SNe Ic by
comparing our observations with predictions from various models that
either include hidden He or in which He has been burnt. Our results
favor the He-free progenitor models for SNe Ic. Finally, we construct
continuum-divided average spectra as a function of subtype and phase
to quantify the spectral diversity of the different types of stripped
SNe.
Description:
We list our SN IIb and Ib samples in Tables 1 and 2, respectively. Our
SN Ic sample is the same as in Modjaz+ (2016ApJ...832..108M 2016ApJ...832..108M).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 212 14 Spectral sample of SNe IIb
table2.dat 202 21 Spectral sample of SNe Ib
table1b.dat 219 17 Spectral sample of SNe Ic; table added by CDS
from Modjaz+ (2016ApJ...832..108M 2016ApJ...832..108M)
table3.dat 104 584 Measured absorption velocities
table4.dat 53 555 Measured "pseudo EW" (pEW) values
(see section 3.2)
refs.dat 139 43 References
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
J/ApJ/825/L22 : BVRI LCs of type Ib supernova iPTF13bvn (Folatelli+, 2016)
J/A+A/593/A68 : PTF12os & iPTF13bvn spectra & light curves (Fremling+, 2016)
J/A+A/574/A60 : Light curve templates of SNe Ib/c from SDSS (Taddia+, 2015)
J/A+A/573/A12 : SN1993J spectra 100-500d post-explosion (Jerkstrand+, 2015)
J/ApJS/213/19 : Optical and near-IR light curves of 64 SNe (Bianco+, 2014)
J/AJ/147/99 : Spectrosc. of 73 stripped core-collapse SNe (Modjaz+, 2014)
J/A+A/562/A17 : SN 2011dh - The first 100 days (Ergon+, 2014)
J/MNRAS/436/774 : Core collapse supernovae (type Ibc) (Eldridge+, 2013)
J/MNRAS/431/308 : SN 2011fu BVRI light curves (Kumar+, 2013)
J/MNRAS/430/1746 : 90 new SNIa from SDSS DR7 (Graur+, 2013)
J/other/PZ/32.6 : UBVRI light curves of SN 2011dh (Tsvetkov+, 2012)
J/MNRAS/425/1819 : Berkeley supernova Ia program. II. (Silverman+, 2012)
J/ApJ/742/L18 : Follow-up photom. of the SN IIb PTF 11eon (Arcavi+, 2011)
J/ApJ/741/97 : Light curves of Ibc supernovae (Drout+, 2011)
J/MNRAS/416/3138 : SN 2009jf light curves (Valenti+, 2011)
J/MNRAS/408/827 : Simulations of supernova explosions (Dessart+, 2010)
J/ApJ/702/226 : Swift/UVOT panchromatic obs. of SN 2008D (Modjaz+, 2009)
J/ApJ/692/L84 : Photometry of SN 2008D (Malesani+, 2009)
J/ApJ/687/1201 : SN and LGRB locations in their host galaxies (Kelly+, 2008)
J/MNRAS/389/955 : u'BVg'r'i'z' light curves of SN 2008ax (Pastorello+, 2008)
J/AJ/131/1648 : Type Ia supernovae at high and low redshifts (Blondin+, 2006)
http://www.cfa.harvard.edu/supernova/SNarchive.html : CfA SN Archive
Byte-by-byte Description of file: table[12].dat table1b.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID SN Name (SN YYYYaa, iPTF13bvn or PTF12gzk)
11- 12 A2 --- f_ID Flag on ID (1)
14-181 A168 --- Phases Phases (2)
183-212 A30 --- Ref Reference(s) (see refs.dat file)
214-219 F6.4 --- z ? Redshift (only for Modjaz+,
2016ApJ...832..108M 2016ApJ...832..108M)
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Note (1): Flag as follows:
c = For this SN, we converted the date of maximum light in the R-band to the
date in the V-band using the relationship found by
Bianco+ (2014, J/ApJS/213/19).
d = Hamuy+ (2009ApJ...703.1612H 2009ApJ...703.1612H) regarded this SN as a broad-line SN IIb
because its early spectra are broad and its inferred kinetic energy of
explosion is large (Mazzali+ 2009ApJ...703.1624M 2009ApJ...703.1624M).
e = For this SN, the date of V-band maximum light is 2453313.69±0.90, which
was determined from the V-band photometry in Drout+ (2011, J/ApJ/741/97)
through the polynomial fitting in Bianco+ (2014, J/ApJS/213/19).
f = The reference for the date of V-band maximum light for this SN is
Tsvetkov+ (2012, J/other/PZ/32.6).
bd = For this SN, the initial classification was an SN Ib/c event by
Hamuy+ (2002AJ....124..417H 2002AJ....124..417H), whereas Parrent+ (2007PASP..119..135P 2007PASP..119..135P)
support the Ib classification and SNID also regards it as a Ib SN. Thus,
we classify it as a SN Ib in this study.
be = For this SN, the date of V-band maximum light is 2453241.18±0.98, which
was determined from the V-band photometry in Drout+ (2011, J/ApJ/741/97)
through the polynomial fitting in Bianco+ (2014, J/ApJS/213/19).
bf = The V-band light curve of this SN shows two distinct maxima. In this
study, the phases are expressed in days from the date of the second
maximum light according to Modjaz+ (2014, J/AJ/147/99).
bg = This SN had spectra that resemble SN Ic-bl spectra after explosion,
i.e., 15-10 days before the date of maximum light, but developed
narrow-line spectra with helium by the date of maximum light
(Mazzali+ 2008Sci...321.1185M 2008Sci...321.1185M, 2009ApJ...703.1624M 2009ApJ...703.1624M;
Modjaz+ 2009, J/ApJ/702/226).
bh = For this SN, the date of V-band maximum light is 2456476.27±0.02, which
was determined from the V-band photometry in
Fremling+ (2014A&A...565A.114F 2014A&A...565A.114F) through the polynomial fitting in
Bianco+ (2014, J/ApJS/213/19).
cc = For SN 1983V, we determine the date of V-band maximum by applying the
polynomial fit as described in Bianco+ (2014, J/ApJS/213/19) to the
original data of C97, to be consistent with the date of
maximum determination for the rest of the SNe in our sample. Our date of
maximum is JDV=2445681.4±1.0, which is 6 days later than the date
obtained in C97 with light curve template fitting.
cd = Note that the dates of maximum for SNe 1990B and 1992ar are uncertain
since their observed light curves start after maximum, and their dates
were estimated via fitting with the light curve of other well-observed
Stripped SNe.
ce = For SN 2004fe, we use the date of V-band maximum as measured by
Bianco+ (2014, J/ApJS/213/19), which is different from that in
Drout+ (2011, J/ApJ/741/97).
cf = For 2011bm, we determine the date of V-band maximum by applying the
polynomial fit as described in Bianco+ (2014, J/ApJS/213/19) to the
original data of V12, and obtain JDV=2455673.7±2.1.
gh = For PTF12gzk, we determine the date of V-band maximum by applying the
polynomial fit as described in Bianco+ (2014, J/ApJS/213/19) to the
original data of B12, and obtain JDV=2456150.1±0.7.
While SNID finds good matches of PTF 12gzk with SN Ic 2004aw, an SN Ic,
we note that it displays very high absorption-velocities (vabs, similar
to those of SN Ic-bl, as inferred from the optical spectra (e.g.,
Ben-Ami+ 2012, J/ApJ/760/L33) and from radio observations
(Horesh+ 2013ApJ...778...63H 2013ApJ...778...63H); see Section 3 in
Modjaz+ 2016ApJ...832..108M 2016ApJ...832..108M for details.
Note (2): Phases are in rest-frame and rounded to the nearest whole day. The
number in brackets is the number of spectra with phases larger than
90 days after or smaller than 20 days before the date of maximum
light. All dates of maximum light were measured in the V-band. The
references for the date of V-band max are the same as references in
the third column unless otherwise noted.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID Supernova identifier
11- 13 A3 --- Type Supernova type
15- 19 F5.1 d Phase Phase (1)
21- 26 I6 km/s VHeI5 [-17400/-4360]? He I 5876A velocity (2)
28- 34 F7.2 km/s e_VHeI5 ? Uncertainty in VHeI5
36- 41 I6 km/s VHeI6 [-20200/-2540]? He I 6678A velocity (2)
43- 48 F6.1 km/s e_VHeI6 ? Uncertainty in VHeI6
50- 55 I6 km/s VHeI7 [-13500/-5550]? He I 7065A velocity (2)
57- 60 I4 km/s e_VHeI7 ? Uncertainty in VHeI7
62- 67 I6 km/s VHa [-32500/-2560]? Hα velocity (2)
69- 75 F7.2 km/s e_VHa ? Uncertainty in VHa
77- 82 I6 km/s VFeII [-21111/-2820]? Fe II 5169A velocity (2)
84- 90 F7.2 km/s e_VFeII ? Uncertainty in VFeII
92- 97 I6 km/s VOI [-11000/-4440]? O I 7774A velocity (2)
99-104 F6.1 km/s e_VOI ? Uncertainty in VOI
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Note (1): Rest-frame age of spectrum in days relative to V-band maximum.
See text for details.
Note (2): For multiple velocity measurements for the same SN of different
spectra taken on the same night, the weighted average is reported,
and the velocity error reported here is the standard deviation of
the weighted average.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID Supernova identifier
11- 13 A3 --- Type Supernova type
15- 19 F5.1 d Phase Phase (1)
21- 23 I3 0.1nm EWHeI5 [15/166]? He I 5876A equivalent width (2)
25- 26 I2 0.1nm e_EWHeI5 ? Uncertainty in EWHeI5 (2)
28- 29 I2 0.1nm EWHeI6 [1/75]? He I 6678A equivalent width (2)
31- 32 I2 0.1nm e_EWHeI6 ? Uncertainty in EWHeI6 (2)
34- 36 I3 0.1nm EWHeI7 [16/148]? He I 7065A equivalent width (2)
38- 39 I2 0.1nm e_EWHeI7 ? Uncertainty in EWHeI7 (2)
41- 43 I3 0.1nm EWHa [8/216]? Hα equivalent width (2)
45- 46 I2 0.1nm e_EWHa ? Uncertainty in EWHa (2)
48- 50 I3 0.1nm EWOI [9/153]? O I 7774A equivalent width (2)
52- 53 I2 0.1nm e_EWOI ? Uncertainty in EWOI (2)
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Note (1): Rest-frame age of spectrum in days relative to V-band maximum.
See text for details.
Note (2): In Angstroms. For multiple measurements for the same SN of different
spectra taken on the same night, the weighted average is reported, and
the error reported here is the standard deviation of the weighted
mean.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Ref Reference code
9- 27 A19 --- BibCode Bibcode
29- 48 A20 --- Auth First author's name(s)
50-139 A90 --- Comm Comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Nov-2016