J/ApJ/832/108 Spectral properties of Type Ic & Ic-bl SNe (Modjaz+, 2016)
The spectral SN-GRB connection: systematic spectral comparisons between Type Ic
supernovae and broad-lined Type Ic supernovae with and without gamma-ray bursts.
Modjaz M., Liu Y.Q., Bianco F.B., Graur O.
<Astrophys. J., 832, 108-108 (2016)>
=2016ApJ...832..108M 2016ApJ...832..108M (SIMBAD/NED BibCode)
ADC_Keywords: Gamma rays ; Supernovae ; Redshifts ; Spectroscopy
Keywords: gamma-ray burst: general; gamma-ray burst: individual: (GRB-980425);
supernovae: general; supernovae: individual: (SN-1994I)
Abstract:
We present the first systematic investigation of spectral properties
of 17 Type Ic Supernovae (SNe Ic), 10 broad-lined SNe Ic (SNe Ic-bl)
without observed gamma-ray bursts (GRBs), and 11 SNe Ic-bl with GRBs
(SN-GRBs) as a function of time in order to probe their explosion
conditions and progenitors. Using a number of novel methods, we
analyze a total of 407 spectra, which were drawn from published
spectra of individual SNe as well as from the densely time-sampled
spectra of Modjaz+ (2014, J/AJ/147/99). In order to quantify the
diversity of the SN spectra as a function of SN subtype, we construct
average spectra of SNe Ic, SNe Ic-bl without GRBs, and SNe Ic-bl with
GRBs. We find that SN 1994I is not a typical SN Ic, contrasting the
general view, while the spectra of SN 1998bw/GRB 980425 are
representative of mean spectra of SNe Ic-bl. We measure the ejecta
absorption and width velocities using a new method described here and
find that SNe Ic-bl with GRBs, on average, have quantifiably higher
absorption velocities, as well as broader line widths than SNe without
observed GRBs. In addition, we search for correlations between SN-GRB
spectral properties and the energies of their accompanying GRBs.
Finally, we show that the absence of clear He lines in optical spectra
of SNe Ic-bl, and in particular of SN-GRBs, is not due to them being
too smeared-out due to the high velocities present in the ejecta. This
implies that the progenitor stars of SN-GRBs are probably free of the
He-layer, in addition to being H-free, which puts strong constraints
on the stellar evolutionary paths needed to produce such SN-GRB
progenitors at the observed low metallicities.
Description:
We list our SN spectral sample and their references in Table 1 for
normal SNe Ic, and in Table 2 for SNe Ic-bl with and without observed
GRBs. We only include SNe with secure spectral IDs (e.g. Modjaz+,
2014, J/AJ/147/99), whose spectra have been published before 2015
February and were made available to us by the authors, and whose date
of maximum light has been measured. With those criteria, we have
included 17 SNe Ic and a total of 23 SNe Ic-bl, both with and without
observed GRBs. However, for only 21 SNe Ic-bl could we measure their
spectral properties.
We analyzed a total of 407 spectra of 11 SNe Ic-bl with GRBs, 10 SNe
Ic-bl without observed GRBs, and 17 SNe Ic.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 206 17 Sample of SNe Ic
table2.dat 206 23 Sample of SNe Ic-bl
table3.dat 31 390 Measured absorption velocities
refs.dat 176 45 References
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See also:
J/ApJ/827/90 : Spectroscopy of SNe Ib, IIb and Ic (Liu+, 2016)
J/MNRAS/450/905 : New SNe in SDSS DR9 (Graur+, 2015)
J/A+A/574/A60 : Light curve templates of SNe Ib/c from SDSS (Taddia+, 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/ApJ/774/114 : GRB 081007 and GRB 090424 light curves (Jin+, 2013)
J/MNRAS/430/1746 : 90 new SNIa from SDSS DR7 (Graur+, 2013)
J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)
J/AJ/143/126 : Spectrosc. of 462 nearby Type Ia supernovae (Blondin+, 2012)
J/ApJ/760/L33 : Photometry of the Ic supernova PTF12gzk (Ben-Ami+, 2012)
J/ApJ/759/107 : Core-collapse SNe and host galaxies (Kelly+, 2012)
J/ApJ/747/L5 : R-band observations of PTF 10vgv (Corsi+, 2012)
J/ApJ/741/97 : Light curves of Ibc supernovae (Drout+, 2011)
J/ApJ/728/14 : Photometry of SN 2009bb (Pignata+, 2011)
J/other/Nat/463.513 : Radio observations of SN 2009bb (Soderberg+, 2010)
J/MNRAS/383/1485 : BVRI light curves of SN 2003jd (Valenti+, 2008)
http://www.cfa.harvard.edu/supernova/SNarchive.html : CfA SN data archive
Byte-by-byte Description of file: table[12].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 21 A21 --- Name SN Name(s)
23- 25 A3 --- f_Name Flag(s) on Name (1)
27 A1 --- l_z Limit flag on z
28- 33 F6.4 --- z [0.001/0.6] Redshift
35-172 A138 --- Phases Phases of spectra with respect to maximum
light (2)
174-197 A24 --- Ref Reference(s) (see refs.dat file)
199-206 A8 --- SN SN identifier as in table 3;
column added by CDS
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Note (1): Flag as follows:
c = 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 (Clocchiatti+, 1997ApJ...483..675C 1997ApJ...483..675C), 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 six days
later than the date obtained in C97 with light-curve template fitting.
d = 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.
e = 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).
f = 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 (Valenti+ 2012ApJ...749L..28V 2012ApJ...749L..28V), and obtain
JDV=2455673.7±2.1.
g = 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 (Ben-Ami+ 2012, J/ApJ/760/L33) and obtain
JDV=2456150.1±0.7.
h = 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). Thus, while we call it an "SN Ic" in the
table, we are not including PTF12gzk when constructing mean spectra of
SN Ic (see Section 3 for details).
i = For consistency, we used the transformations of
Bianco+ (2014, J/ApJS/213/19) to convert the dates of maximum in the B or
R bands into that in the V band because no V-band data have been provided.
j = While Corsi+ (2012, J/ApJ/747/L5) classify PTF10vgv as an SN Ic based on
its measured low SiIIλ6355 absorption velocities, its optical
spectra show broad lines and are clearly those of an SN Ic-bl, with SNID
finding good matches with only SNe Ic-bl. Thus we reclassify this object
as an SN Ic-bl, following our classification approach outlined in M14
(Modjaz+, 2014, J/AJ/147/99).
k = These SN-GRB harbored low-luminosity GRBs.
l = We include SNe 2009bb and 2012ap as "engine-driven" SNe Ic-bl, since they
have been suggested to be relativistic SNe based on their large radio
emission, similar to, albeit weaker than, nearby SN-GRBs, even if no
gamma-rays were detected (Soderberg+ 2010, J/other/Nat/463.513;
Margutti+ 2014ApJ...797..107M 2014ApJ...797..107M).
m = For SN 2009nz/GRB 091117, Berger+ (2011ApJ...743..204B 2011ApJ...743..204B) did not provide us
with their published spectrum, so we had to digitize their Figure 1, which
shows their smoothed spectrum. Thus, some of our analysis, which requires
the raw spectrum, could not be performed.
n = While Cano+ (2014, J/A+A/568/A19) suggest that SN 2013ez/GRB 130215A is an
SN Ic, SNID finds good matches with both SNe Ic-bl (including
SNe Ic-bl 2007ce and 2005nb ) and with SNe Ic. Thus, we call it
an "SN Ic/Ic-bl," since SNID does not find an unambiguous type, and we do
not include it when constructing mean spectra of SNe Ic-bl. Furthermore,
the redshift of this SN/GRB is uncertain, as there is only a lower limit
from metal absorption lines superimposed on the GRB afterglow spectrum as
mentioned in the GCN by Cucchiara & Fumagalli (2013GCN..14207...1C).
Note (2): Phases are in the rest frame with respect to V-band maximum light,
either directly measured (as listed in Modjaz+ 2014, J/AJ/147/99) or in the
original papers or using the polynomial fit as described in
Bianco+ 2014, J/ApJS/213/19 or transformed (see the text for details). Phases
are rounded to the nearest whole day. The number in a bracket is the number of
spectra with phases larger than 90 days after the date of maximum light
--spectra that we include for completeness but do not analyze here.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- SN Supernova, snYYYYaa
10- 14 F5.1 d Phase [-15/116] Phase (1)
16- 21 I6 km/s vabs [-49000/-2600] Absorption velocity (vabs),
FeIIλ5169
23- 26 I4 km/s E_vabs [61/6200]? Positive velocity uncertainty on vabs
28- 31 I4 km/s e_vabs [160/9000] Negative or symmetric (if E_vabs is
null) uncertainty on vabs
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Note (1): Rest-frame age of spectrum in days relative to V-band maximum.
See text for details.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- Ref Reference code
6- 24 A19 --- BibCode Bibcode
26- 45 A20 --- Auth First author's name
47-176 A130 --- Comm Comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Feb-2017