J/ApJ/773/53 Type Ia SNe spectroscopy by the CSP (Folatelli+, 2013)
Spectroscopy of type Ia supernovae by the Carnegie Supernova Project.
Folatelli G., Morrell N., Phillips M.M., Hsiao E., Campillay A.,
Contreras C., Castellon S., Hamuy M., Krzeminski W., Roth M.,
Stritzinger M., Burns C.R., Freedman W.L., Madore B.F., Murphy D.,
Persson S.E., Prieto J.L., Suntzeff N.B., Krisciunas K., Anderson J.P.,
Forster F., Maza J., Pignata G., Rojas P.A., Boldt L., Salgado F.,
Wyatt P., Olivares E.F., Gal-Yam A., Sako M.
<Astrophys. J., 773, 53 (2013)>
=2013ApJ...773...53F 2013ApJ...773...53F
ADC_Keywords: Supernovae ; Spectroscopy ; Equivalent widths ; Redshifts
Keywords: galaxies: distances and redshifts; supernovae: general;
techniques: spectroscopic
Abstract:
This is the first release of optical spectroscopic data of
low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova
Project including 604 previously unpublished spectra of 93 SNe Ia. The
observations cover a range of phases from 12 days before to over 150
days after the time of B-band maximum light. With the addition of 228
near-maximum spectra from the literature, we study the diversity among
SNe Ia in a quantitative manner. For that purpose, spectroscopic
parameters are employed such as expansion velocities from spectral
line blueshifts and pseudo-equivalent widths (pW). The values of those
parameters at maximum light are obtained for 78 objects, thus
providing a characterization of SNe Ia that may help to improve our
understanding of the properties of the exploding systems and the
thermonuclear flame propagation. Two objects, namely, SNe 2005M and
2006is, stand out from the sample by showing peculiar Si II and S II
velocities but otherwise standard velocities for the rest of the ions.
We further study the correlations between spectroscopic and
photometric parameters such as light-curve decline rate and color. In
agreement with previous studies, we find that the pW of Si II
absorption features are very good indicators of light-curve decline
rate. Furthermore, we demonstrate that parameters such as pW2 (Si II
4130) and pW6 (Si II 5972) provide precise calibrations of the peak
B-band luminosity with dispersions of ~0.15mag. In the search
for a secondary parameter in the calibration of peak luminosity for
SNe Ia, we find a ~2σ-3σ correlation between B-band
Hubble residuals and the velocity at maximum light of S II and Si II
lines.
Description:
We present optical spectroscopic data for a sample of 93 SNe Ia
observed by the Carnegie Supernova Project (CSP; Hamuy et al.
2006PASP..118....2H 2006PASP..118....2H) between 2004 and 2009. The data set amounts to
832 optical spectra, 569 of which were obtained by the CSP, 35 were
provided by other observers, and 228 were taken from the literature.
Most of the data were obtained with the 2.5m du Pont Telescope at Las
Campanas Observatory, using the Wide Field CCD Camera (WFCCD) in
long-slit spectroscopy mode. Other instruments used to improve our
spectroscopic time coverage were the Las Campanas Modular Spectrograph
at the du Pont, the Low Dispersion Survey Spectrograph (LDSS2) on the
Magellan Clay 6.5m telescope, and the Ritchey-Chretien spectrograph at
the 1.5m CTIO telescope, operated by the SMARTS consortium. In
addition to these, more recently we have also employed, at Las
Campanas: LDSS3 on the Magellan Clay telescope (an upgrade of LDSS2,
with new grisms and different long slits); the Inamori Magellan Areal
Camera and Spectrograph (IMACS) on the Magellan Baade 6.5m telescope;
the Boller and Chivens spectrograph at the du Pont telescope; and
finally, a few spectra have been obtained using the Magellan
Echellette (MagE) spectrograph on the Magellan Clay telescope. We have
also obtained single nights with the New Technology Telescope (NTT)
and the 3.6m Telescope at ESO-La Silla, using the ESO Multi-Mode
Instrument (EMMI) in medium resolution spectroscopy mode (at the NTT)
and the ESO Faint Object Spectrograph and Camera (EFOSC) at the 3.6m
and NTT telescopes. A few spectra have been obtained with the Gemini
Multi-Object Spectrograph (GMOS) mounted on the Gemini South
Telescope. In Table 2, we provide a complete journal of the
spectroscopic observations considered in this work.
Table 1 lists the sample of SNe Ia selected for this work along with
the amount and span of spectroscopy epochs, and spectral
classification as defined in Section 4.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 121 93 Summary of observations, classification, and
photometric properties of the SN-Ia sample
table2.dat 84 605 Previously unpublished spectroscopic observations
for 92 SN-Ia
table3.dat 95 78 Values of velocity at B-band maximum light, and
SiIIλ6355 velocity decline
table6.dat 93 78 Values of pW at B-band maximum light
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See also:
B/sn : Asiago Supernova Catalogue (Barbon et al., 1999-)
J/MNRAS/425/1819 : Berkeley supernova Ia program. II. (Silverman+, 2012)
J/A+A/538/A120 : A unified supernova catalogue (Lennarz+, 2012)
J/AJ/143/126 : Spectroscopy of nearby Type Ia supernovae (Blondin+, 2012)
J/ApJS/200/12 : CfA4: light curves for 94 type Ia SNe (Hicken+, 2012)
J/ApJ/748/L29 : SN Ia supernovae observed by Swift/XRT (Russell+, 2012)
J/ApJ/746/85 : THe HST Cluster Supernova Survey. V. (Suzuki+, 2012)
J/ApJ/745/74 : Pre-maximum spectra of type Ia SNe (Folatelli+, 2012)
J/ApJ/742/89 : Relations between spectra & colors of SNe Ia (Foley+, 2011)
J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
J/MNRAS/412/1441 : SNe luminosity functions (Li+, 2011)
J/ApJ/731/120 : Intrinsic SN Ia light curves (Mandel+, 2011)
J/MNRAS/410/1262 : Supernova Legacy Survey. Type Ia supernovae (Walker+, 2011)
J/MNRAS/406/782 : Type Ia supernovae luminosities (Sullivan+, 2010)
J/ApJ/716/712 : HST light curves of six SNe and Union2 (Amanullah+, 2010)
J/AJ/139/519 : Carnegie supernova project. SNe Ia (Contreras+, 2010)
J/AJ/139/120 : Low-redshift Type-Ia supernovae (Folatelli+, 2010)
J/ApJ/700/1097 : Light curve parameters of SN Ia (Hicken+, 2009)
J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)
J/A+A/500/L17 : Spectral flux ratio of SN Ia (Bailey+, 2009)
J/A+A/477/717 : Spectroscopy of Type Ia supernovae (Bronder+, 2008)
J/AJ/135/1598 : Optical spectroscopy of type Ia supernovae (Matheson+, 2008)
J/MNRAS/377/1531 : Optical+IR photometry of SN 2004eo (Pastorello+, 2007)
J/AJ/131/1648 : Type Ia SNe at high and low redshifts (Blondin+, 2006)
http://csp.obs.carnegiescience.edu/ : Carnegie Supernova Project home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- SN SN name (YYYYaa) (1)
8- 9 I2 --- N [0/19]? Number of spectroscopic epochs
11- 15 F5.1 d Ep1 [-13/43]? Epoch minimum range (2)
17- 22 F6.1 d Ep2 [-5/285]? Epoch maximum range (2)
24- 31 A8 --- Type Spectral subtype based on SNID comparisons
(Blondin & Tonry 2007ApJ...666.1024B 2007ApJ...666.1024B)
33- 36 A4 --- Wst Spectral subtype based on the scheme of
Wang et al. (3)
38- 39 A2 --- Bst Spectral subtype based on pW (4)
41- 47 F7.5 --- z [0.004/0.09]? Heliocentric redshift from NED,
except flagged
48 A1 --- f_z [a] Redshift of host galaxy (5)
50- 56 F7.5 --- zCMB [0.004/0.09]? redshift in the 3K CMB frame
converted from z using the NED application
58- 64 F7.1 d T0 ? Reduced Julian Date (JD-2400000) of B-band
maximum light
66- 71 F6.3 mag Bmag [12.2/19]? Corrected apparent B-band peak
magnitude (6)
73- 77 F5.3 mag e_Bmag [0.005/0.2]? Bmag uncertainty
79- 83 F5.3 mag Dm15 [0.7/2]? Observed decline rate, Δm15(B)
85- 89 F5.3 mag e_Dm15 [0.005/0.3]? Dm15 uncertainty
91- 95 F5.3 mag E(B-V) [0/0.4]? Galactic reddening from NED
97-102 F6.3 mag B-V [-0.2/1.2]? Pseudo-color at maximum light
104-108 F5.3 mag e_B-V [0.008/0.2]? B-V uncertainty
110 A1 --- n_B-V [Y] Low host-galaxy reddening? (7)
112-116 F5.2 mag DBMag [-0.7/0.8]? B-band absolute peak magnitude
residual (ΔMB) (8)
118-121 F4.2 mag e_DBMag [0.06/0.6]? DBMag uncertainty
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Note (1): SN 2005hj has been added by CDS for consistencies with Tables 3 and 6
even though no spectra was taken by the CSP;
we acknowledge Gaston Folatelli (Kavli Institute for the Physics and
Mathematics of the Universe) for sending data about this object.
Note (2): Epoch range of previously unpublished spectra relative to B-band
maximum light.
Note (3): spectral subtype based on the scheme of Wang et al. 2009
(J/ApJ/699/L139), as follows;
N = normal,
91T = SN 1991T-like,
91bg = SN 1991bg-like,
HV = high velocity
Note (4): spectral subtype based on pseudo equivalent widths
(Branch et al. 2006PASP..118..560B 2006PASP..118..560B), as follows;
CN = core normal,
CL = cool,
BL = broad line,
SS = shallow silicon
Note (5):
a = Redshift computed from spectrum of the host galaxy obtained by the CSP.
Note (6): K-corrected, apparent B-band peak magnitude, corrected for dust
extinction in the Galaxy.
Note (7): "Y" indicates the SN is considered to have suffered negligible
host-galaxy reddening.
Note (8): The peak absolute magnitude residuals were computed as in
Equation (6) (see section 5.3; µ is the distance modulus)
ΔMB = Bmax - µ + 19.16 - 3.05(Bmax-Vmax)
- 0.55[Δm15(B)-1.1],
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- --- [SN]
4- 9 A6 --- SN SN identifier (YYYYaa)
11- 24 A14 "YYYY/MM/DD" Date UT date of the observation (in decimal days)
26- 29 A4 --- fs Corrected spectrum (1)
31- 39 F9.3 d JD Julian Date of the observation; JD-2400000
41- 45 F5.1 d Phase Phase in rest-frame days since B maximum light
47- 49 A3 --- Tel Telescope used in the observation (2)
51- 52 A2 --- Inst Instrument used in the observation (3)
54- 57 I4 0.1nm lam0 [3100/7578] Lower wavelength range; in Å
59- 63 I5 0.1nm lam1 [5300/10889] Upper wavelength range; in Å
65- 68 F4.1 0.1nm Res [0.5/39] Resolution; in Angstroms (4)
70- 73 I4 s Exp [90/7200] Total exposure time
75- 78 F4.2 --- AirM [1/2.9] Airmass at middle of the observation
80- 84 F5.3 mag rms [0.002/0.6]? RMS difference (5)
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Note (1): Flag as follows:
dg = Spectrum corrected to match photometry (see Section 2.2).
dd = Spectrum uncorrected for telluric absorption (see Section 2.2).
Note (2): Telescope as follows:
3P6 = ESO 3.6 m Telescope;
BAA = Las Campanas Magellan I 6.5 m Baade Telescope;
CLA = Las Campanas Magellan II 6.5 m Clay Telescope;
DUP = Las Campanas 2.5 m du Pont Telescope Telescope;
GEM = Gemini-S 8.1 m Telescope;
HIL = Hiltner 2.4 m Telescope;
MGH = McGraw-Hill 1.3 m Telescope;
NTT = New Technology Telescope;
P20 = Palomar 200 inch Hale Telescope;
T60 = CTIO 1.5 m Telescope.
Note (3): Instrument as follows:
BC = Boller & Chivens spectrograph;
CS = Ritchey-Chretien spectrograph;
DB = Double Spectrograph;
EF = ESO Faint Object Spectrograph and Camera (EFOSC-2);
EM = ESO Multi-Mode Instrument (EMMI);
GM = Gemini Multi-Object Spectrographs (GMOS);
IM = Inamori Magellan Areal Camera and Spectrograph (IMACS),
LD = Low Dispersion Survey Spectrograph (LDSS);
MA = Magellan Echellette spectrograph (MagE);
MS = Las Campanas Modular Spectrograh;
WF = Wide Field Reimaging CCD Camera (WFCCD).
Note (4): As estimated from arc-lamp lines.
Note (5): Between synthetic and observed broadband magnitudes.
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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- 2 A2 --- Cl Classification scheme (G1)
4- 9 A6 --- SN SN identifier (YYYYaa)
11- 15 I5 km/s V(HK) ? CaII H&K velocity
17- 20 I4 km/s e_V(HK) ? Uncertainty in V(HK)
22- 26 I5 km/s V(4130) ? SiII 4130Å velocity
28- 31 I4 km/s e_V(4130) ? Uncertainty in V(4130)
33- 37 I5 km/s V(5449) ? SII 5449Å velocity
39- 42 I4 km/s e_V(5449) ? Uncertainty in V(5449)
44- 48 I5 km/s V(5622) ? SII 5622Å velocity
50- 53 I4 km/s e_V(5622) ? Uncertainty in V(5622)
55- 59 I5 km/s V(5972) ? SiII 5972Å velocity
61- 64 I4 km/s e_V(5972) ? Uncertainty in V(5972)
66- 70 I5 km/s V(6355) [8761/16232] Si II 6355Å velocity
72- 74 I3 km/s e_V(6355) [22/881] Uncertainty in V(6355)
76- 80 I5 km/s V(Ca-IR) ? CaII-IR velocity
82- 85 I4 km/s e_V(Ca-IR) ? Uncertainty in V(Ca-IR)
87- 90 I4 km/s Dv20 [167/5047]? SiII 6355Å velocity decline (1)
92- 95 I4 km/s e_Dv20 ? Uncertainty in Dv20
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Note (1): Δv20(Si), difference ion the velocity of the SiII 6355Å
line between the maximum light and 20days later
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Cl Classification scheme (G1)
4- 9 A6 --- SN SN identifier (YYYYaa)
11- 15 F5.1 0.1nm pW1 ? Pseudo-equivalent width of Ca II H&K (1)
17- 20 F4.1 0.1nm e_pW1 ? Uncertainty in pW1 (1)
22- 25 F4.1 0.1nm pW2 ? Pseudo-equivalent width of Si II 4130 (1)
27- 29 F3.1 0.1nm e_pW2 ? Uncertainty in pW2 (1)
31- 35 F5.1 0.1nm pW3 ? Pseudo-equivalent width of Mg II (1)
37- 40 F4.1 0.1nm e_pW3 ? Uncertainty in pw3 (1)
42- 46 F5.1 0.1nm pW4 ? Pseudo-equivalent width of Fe II (1)
48- 51 F4.1 0.1nm e_pW4 ? Uncertainty in pw4 (1)
53- 57 F5.1 0.1nm pW5 Pseudo-equivalent width of S II W (1)
59- 62 F4.1 0.1nm e_pW5 Uncertainty in pw5 (1)
64- 67 F4.1 0.1nm pW6 Pseudo-equivalent width of Si II 5972 (1)
69- 71 F3.1 0.1nm e_pW6 Uncertainty in pw6 (1)
73- 77 F5.1 0.1nm pW7 [53/184] Pseudo-equivalent width of Si II 6355 (1)
79- 82 F4.1 0.1nm e_pW7 [0.2/37] Uncertainty in pw7 (1)
84- 88 F5.1 0.1nm pW8 ? Pseudo-equivalent width of Ca II IR (1)
90- 93 F4.1 0.1nm e_pW8 ? Uncertainty in pw8 (1)
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Note (1): In units of Angstroms.
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Global note:
Note (G1): Classification scheme as follows:
CN = Core Normal;
CL = Cool;
BL = Broad Line;
SS = Shallow Silicon.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 18-Feb-2015