J/MNRAS/492/4325 BSNIP Spectroscopy of 247 type Ia supernovae (Stahl+, 2020) ================================================================================ Berkeley supernova Ia program: data release of 637 spectra from 247 Type Ia supernovae. Stahl B.E., Zheng W., de Jaeger T., Brink T.G., Filippenko A.V., Silverman J.M., Cenko S.B., Clubb K.I., Graham M.L., Halevi G., Kelly P.L., Kleiser I., Shivvers I., Yuk H., Cobb B.E., Fox O.D., Kandrashoff M.T., Kong J.J., Mauerhan J.C., Wang X., Wang X. =2020MNRAS.492.4325S (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Supernovae ; Redshifts ; Spectra, optical Keywords: techniques: spectroscopic - surveys - supernovae: general distance scale - cosmology: observations Abstract: We present 637 low-redshift optical spectra collected by the Berkeley Supernova Ia Program (BSNIP) between 2009 and 2018, almost entirely with the Kast double spectrograph on the Shane 3 m telescope at Lick Observatory. We describe our automated spectral classification scheme and arrive at a final set of 626 spectra (of 242 objects) that are unambiguously classified as belonging to Type Ia supernovae (SNe Ia). Of these, 70 spectra of 30 objects are classified as spectroscopically peculiar (i.e. not matching the spectral signatures of 'normal' SNe Ia) and 79 SNe Ia (covered by 328 spectra) have complementary photometric coverage. The median SN in our final set has one epoch of spectroscopy, has a redshift of 0.0208 (with a low of 0.0007 and high of 0.1921), and is first observed spectroscopically 1.1d after maximum light. The constituent spectra are of high quality, with a median signal-to-noise ratio of 31.8pixel^-1^, and have broad wavelength coverage, with ~95 per cent covering at least 3700-9800{AA}. We analyse our data set, focusing on quantitative measurements (e.g. velocities, pseudo-equivalent widths) of the evolution of prominent spectral features in the available early-time and late-time spectra. The data are available to the community, and we encourage future studies to incorporate our spectra in their analyses. Description: All Berkeley Supernova Ia Program (BSNIP) spectroscopy, along with useful metadata for those observations and the SNe in them (e.g. observer, reducer, host galaxy, redshift), are catalogued in our UC Berkeley SuperNova DataBase (SNDB; Silverman et al. 2012MNRAS.425.1789S, Cat. J/MNRAS/425/1789, Shivvers et al. 2016MNRAS.461.3057S) after the data are processed and reduced. Therefore, to collect the data set presented herein, we simply query the private (pre-publication) portion of our SNDB for all spectra observed between 2009 January 1 and 2018 December 31 for objects spectroscopically classified as SNe Ia. This results in 744 matches, which we then filter by (i) selecting only those spectra with an average signal-to-noise ratio (SNR) greater than 5/pixel and (ii) retaining only those with a wavelength coverage of at least 3700-7000{AA}. Finally, we remove several of the remaining spectra, including any that are from SNe discovered earlier than 2008 January 1, to obtain a set of 637 spectra. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file tablea1.dat 93 247 SN Ia information tables1.dat 92 637 SN Ia spectral information tables2.dat 97 608 SNID classification results table3.dat 51 9 Spectral features tables4.dat 89 1154 SN Ia spectral feature measurements near maximum brightness -------------------------------------------------------------------------------- Byte-by-byte Description of file: tablea1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 23 A23 --- Name Supernova name 25- 34 I10 "Y:M:D" Discov Discovery date (UT) 36- 43 F8.4 deg RAdeg Right ascension (J2000) 45- 52 F8.4 deg DEdeg Declination (J2000) 54- 59 F6.4 --- z ? Heliocentric redshift mostly from NED 61 A1 --- r_z Reference for z (1) 63- 67 F5.3 mag E(B-V) Extinction calculated at the supernova position (2) 69- 75 A7 --- Subtype Supernova subtype (3) 77- 78 I2 --- Nsp Number of spectra 80- 84 F5.1 d fepoch ? First observation epoch (4) 86- 90 F5.1 d lepoch ? Last observation epoch (4) 92- 93 I2 --- Ref ? Reference for the light-curve-determined MJD corresponding to B-band maximum brightness (5) -------------------------------------------------------------------------------- Note (1): Flag as follows: c = Supernova catalogue of Lennarz, Altmann & Wiebusch (2012A&A...538A.120L, Cat. J/A+A/538/A120) p = Spectroscopic host-galaxy observations of PTF SNe Ia described by Pan et al. (2014MNRAS.438.1391P, Cat. J/MNRAS/438/1391) t = Transient Name Server (TNS) w = Weizmann Interactive Supernova Data Repository Yaron & Gal-Yam (WISeREP 2012PASP..124..668Y) d = Appropriate discovery or classification announcement (e.g. CBET or IAUC) Note (2): Extinction calculated using the dust maps of Schlegel, Finkbeiner & Davis (1998ApJ...500..525S) subject to the recalibration of Schlafly & Finkbeiner (2011ApJ...737..103S) Note (3): SN classifications are derived from our SNID classification scheme, as described in Section 3. Based on the arguments made by Foley et al. (2013ApJ...767...57F), we have relabelled all SNe Ia with a 'Ia-02cx' subtype as 'Iax' Note (4): First and last observation epochs are in rest-frame days relative to the time of B-band maximum brightness and are computed using information from the table Note (5): References as follows: 1 = Stahl et al. (2019MNRAS.490.3882S) (S19) 2 = Friedman et al. (2015ApJS..220....9F, Cat. J/ApJS/220/9) and references therein 3 = Foley et al. (2018MNRAS.475..193F, Cat. J/MNRAS/475/193) 4 = Krisciunas et al. (2017AJ....154..211K, Cat. J/AJ/154/211) 5 = Maguire et al. (2014MNRAS.444.3258M, Cat. J/MNRAS/444/3258) 6 = Khan et al. (2011ApJ...726..106K) 7 = Zhang et al. (2014AJ....148....1Z, Cat. J/AJ/148/1) 8 = Yamanaka et al. (2014ApJ...782L..35Y) 9 = Shappee et al. (2016ApJ...826..144S, Cat. J/ApJ/826/144) 10 = Srivastav et al. (2017MNRAS.466.2436S) -------------------------------------------------------------------------------- Byte-by-byte Description of file: tables1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 23 A23 --- Name Supernova name 25- 38 F14.3 "Y:M:D" UTDate UT date for the temporal midpoint of the associated observation 40- 44 F5.1 d tLC ? Phase in rest-frame days as computed from the appropriate redshift and photometry from Table A1 46 I1 --- Inst [1/2] Instrument used for observation (1) 48- 51 I4 0.1nm lambdamin Wavelength range (minimum value) 53- 57 I5 0.1nm lambdamax Wavelenght range (maximum value) 59- 62 F4.1 0.1nm Resb ? Spectral resolution for the blue component 64- 67 F4.1 0.1nm Resr ? Spectral resolution for the red component 69- 73 F5.1 deg PA []? Observed slit position angle 75- 78 F4.2 --- Airmass ? Airmass for the temporal midpoint of the associated observation 80- 83 I4 s ExpTime ? Exposure time 85- 89 F5.1 --- S/N Signal to noise ratio 91- 92 I2 --- Ref ? References (2) -------------------------------------------------------------------------------- Note (1): Instrument as follows: 1 = Kast (Shane 3 m) 2 = LRIS (Keck-I 10 m) Note (2): References as follows: 1 = Silverman et al. (2011MNRAS.410..585S, Cat. J/MNRAS/410/585) 2 = Foley et al. (2012ApJ...744...38F) 3 = Foley et al. (2013ApJ...767...57F) 4 = Silverman et al. (2013MNRAS.430.1030S) 5 = Mazzali et al. (2015MNRAS.450.2631M) 6 = Silverman et al. (2012ApJ...756L...7S) 7 = Childress et al. (2013ApJ...770...29C) 8 = Zheng et al. (2013ApJ...778L..15Z) 9 = Pan et al. (2015MNRAS.452.4307P, Cat. J/MNRAS/452/4307) 10 = Foley et al. (2015ApJ...798L..37F) 11 = Foley et al. (2016MNRAS.461..433F) 12 = Zheng et al. (2017ApJ...841...64Z) 13 = Xuhui et al. (2019, in prep.) -------------------------------------------------------------------------------- Byte-by-byte Description of file: tables2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 23 A23 --- Name Supernova name 25- 26 A2 --- Type Supernova type 28- 35 A8 --- Subtype Supernova subtype 37- 42 F6.4 --- zSNID ? SNID redshift 44- 49 F6.4 --- e_zSNID ? Error on zSNID 51- 55 F5.1 d tSNID ? SNID spectral age in rest-frame days relative to the time of the associated SN's maximum brightness 57- 60 F4.1 d e_tSNID ? Error on tSNID 62- 69 A8 --- SName Name of the best-matching SNID template 71- 78 A8 --- SSubtype Subtype of the best-matching SNID template 80- 83 F4.1 --- rlap Measure of quality used by SNID (1) 85- 91 F7.4 --- z Redshift of the best-matching SNID template 93- 97 F5.1 d t Spectral age of the best-matching SNID template -------------------------------------------------------------------------------- Note (1): Higher values of rlap correspond to classifications that are more trustworthy -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 21 A21 --- Feature Spectral feature 23- 29 F7.2 0.1nm restwvl ? Rest wavelength 31 A1 --- f_restwvl [a] Flag on restwvl (1) 33- 41 A9 0.1nm bboundary Blue boundary of the absorption feature 43- 51 A9 0.1nm rboundary Red boundary of the absorption feature -------------------------------------------------------------------------------- Note (1): Flag as follows: a = A single reference wavelength is not useful for this feature because it is a blend of too many spectral lines. Hence, we do not compute expansion velocities for this feature. -------------------------------------------------------------------------------- Byte-by-byte Description of file: tables4.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 11 A11 --- Name Supernova name 13- 33 A21 --- Feature Spectral feature 35- 40 F6.2 d tLC Phases in rest-frame days 42- 47 F6.2 10-2W/m2/nm Fb Flux within the blue edge boundary 49- 53 F5.2 10-2W/m2/nm e_Fb Error on Fb 55- 60 F6.2 10-2W/m2/nm Fr Flux within the red edge boundary 62- 66 F5.2 10-2W/m2/nm e_Fr Error on Fr 68- 72 F5.1 0.1nm pEW Pseudo-equivalent width 74- 77 F4.1 0.1nm e_pEW Error on pEW 79- 84 F6.2 10+3km/s v ? Expansion velocity (blueshift) 86- 89 F4.2 10+3km/s e_v ? Error on v -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Ana Fiallos [CDS] 28-Mar-2023