J/ApJ/905/93 Classification of PS1-MDS SNe with Superphot (Hosseinzadeh+, 2020)
Photometric classification of 2315 Pan-STARRS1 supernovae with Superphot.
Hosseinzadeh G., Dauphin F., Villar V.A., Berger E., Jones D.O.,
Challis P., Chornock R., Drout M.R., Foley R.J., Kirshner R.P., Lunnan R.,
Margutti R., Milisavljevic D., Pan Y.-C., Rest A., Scolnic D.M.,
Magnier E., Metcalfe N., Wainscoat R., Waters C.
<Astrophys. J., 905, 93 (2020)>
=2020ApJ...905...93H 2020ApJ...905...93H
ADC_Keywords: Supernovae ; Redshifts; Extinction; Spectral types; Photometry;
Optical
Keywords: Supernovae ; Astrostatistics ; Light curve classification
Abstract:
The classification of supernovae (SNe) and its impact on our
understanding of explosion physics and progenitors have traditionally
been based on the presence or absence of certain spectral features.
However, current and upcoming wide-field time-domain surveys have
increased the transient discovery rate far beyond our capacity to
obtain even a single spectrum of each new event. We must therefore
rely heavily on photometric classification-connecting SN light curves
back to their spectroscopically defined classes. Here, we present
Superphot, an open-source Python implementation of the
machine-learning classification algorithm of
Villar+ (2019ApJ...884...83V 2019ApJ...884...83V), and apply it to 2315 previously
unclassified transients from the Pan-STARRS1 Medium Deep Survey for
which we obtained spectroscopic host-galaxy redshifts. Our classifier
achieves an overall accuracy of 82%, with completenesses and purities
of >80% for the best classes (SNe Ia and superluminous SNe). For the
worst performing SN class (SNe Ibc), the completeness and purity fall
to 37% and 21%, respectively. Our classifier provides 1257 newly
classified SNe Ia, 521 SNe II, 298 SNe Ibc, 181 SNe IIn, and 58 SLSNe.
These are among the largest uniformly observed samples of SNe
available in the literature and will enable a wide range of
statistical studies of each class.
Description:
Pan-STARRS1 is a 1.8m telescope near the summit of Haleakala
Hawai'i, equipped with a 1.4 gigapixel camera with a 7deg2 field of
view. Pan-STARRS1 Medium Deep Survey (PS1-MDS; Chambers+ 2016, II/349)
using 25% of the observing time on Pan-STARRS1 and consisted of 10
deep-drilling fields with a three-day cadence in any of five bands:
grizy.
Over the course of PS1-MDS, we detected a total of 5243 SN-like
transients using photpipe. These light curves are presented in a
companion paper by Villar+ (2020, J/ApJ/905/94). We obtained
spectroscopic classifications of 573 of these transients.
We also obtained host-galaxy spectra for 4233 transients, 3600 of
which were not classified spectroscopically: 3434 from MMT, 324 from
the Anglo-Australian Telescope (AAT), 301 from WIYN, 169 from the
Sloan Digital Sky Survey (SDSS), and 5 from Apache Point Observatory
(APO). We used RVSAO (Kurtz & Mink 1998PASP..110..934K 1998PASP..110..934K) to
cross-correlate these spectra with a library of galaxy templates.
Table 1 logs these observations and lists the modes of the resulting
redshift distribution from RVSAO, ignoring matches with z<0.005.
See Section 2.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 76 10465 Host galaxy redshifts from RVSAO
(Kurtz & Mink 1998PASP..110..934K 1998PASP..110..934K)
table3.dat 78 2315 Classification results
table4.dat 84 557 Cross-validation results
table5.dat 87 16 Rare transients
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See also:
III/250 : The VIMOS VLT deep survey (VVDS-DEEP) (Le Fevre+ 2005)
VII/259 : 6dF galaxy survey final redshift release (Jones+, 2009)
I/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
V/154 : SDSS Release 16 (DR16) (Ahumada+, 2020)
J/ApJS/78/1 : Galaxies in 7 clusters 0.35<z<0.55 (Dressler+, 1992)
J/ApJ/607/665 : Type Ia supernovae at z>1 discovered by HST (Riess+, 2004)
J/ApJS/155/271 : Chandra Deep Field-South: Opt. spectroscopy (Szokoly+, 2004)
J/MNRAS/372/425 : 2dF-SDSS Luminous Red Galaxy Survey, 2SLAQ (Cannon+, 2006)
J/AJ/132/2409 : Deep ATLAS radio observations of CDFS (Norris+, 2006)
J/A+A/474/473 : XMM-LSS survey: AGN classifications (Garcet+, 2007)
J/ApJ/659/122 : Improved distances to type Ia supernovae (Jha+, 2007)
J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007)
J/A+A/467/73 : 3σ hard sample of XMDS survey (Tajer+, 2007)
J/A+A/477/717 : Spectroscopy of Type Ia supernovae (Bronder+, 2008)
J/MNRAS/387/1323 : SDSS photometry of luminous red galaxies (Ross+, 2008)
J/A+A/495/53 : Physical properties of VVDS galaxies (Lamareille+, 2009)
J/ApJS/182/625 : WIYN spectroscopy in the deep SWIRE field (Owen+, 2009)
J/ApJ/696/1195 : COSMOS AGN spectroscopic survey. I. (Trump+, 2009)
J/A+A/512/A12 : VLT/VIMOS spectroscopy in GOODS-S field (Balestra+, 2010)
J/ApJ/711/928 : Low-redshift Lyα galaxies from GALEX (Cowie+, 2010)
J/MNRAS/401/1429 : WiggleZ dark energy survey (DR1) (Drinkwater+, 2010)
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/MNRAS/401/294 : Optical identification of XMM-LSS sources (Stalin+, 2010)
J/A+A/529/A135 : AGN Opt/IR properties in Lockman Hole (Rovilos+, 2011)
J/ApJ/738/162 : SN Ia candidates from the SDSS-II SN Survey (Sako+, 2011)
J/MNRAS/422/25 : SDSS DR7 groups, clusters and filaments (Smith+, 2012)
J/ApJ/769/39 : SN Ibn PS1-12sk optical & NIR light curves (Sanders+, 2013)
J/ApJS/213/19 : Optical and near-IR light curves of 64 SNe (Bianco+, 2014)
J/ApJ/794/23 : Pan-STARRS1 transients optical photometry (Drout+, 2014)
J/MNRAS/441/1802 : Low-redshift QSOs in SDSS Stripe 82 (Karhunen+, 2014)
J/ApJ/795/44 : PS1 SNe Ia (0.02<z<0.7) griz light curves (Rest+, 2014)
J/ApJ/799/208 : Type IIP supernovae from Pan-STARRS1 (Sanders+, 2015)
J/A+A/574/A60 : Light curve templates of SNe Ib/c from SDSS (Taddia+, 2015)
J/ApJ/807/178 : Rich galaxy clusters identified in SDSS-DR12 (Wen+, 2015)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJ/837/120 : Lick Observatory SN Search (LOSS) revisited (Graur+, 2017)
J/ApJ/858/77 : DEIMOS 10K sp. survey in COSMOS field (Hasinger+, 2018)
J/ApJ/857/51 : Dark energy properties with PS1 SNe. II. (Jones+, 2018)
J/ApJ/852/81 : 17 PS1 superluminous SNe LCs + classif. sp. (Lunnan+, 2018)
J/A+A/609/A134 : CSP-I photometry for 34 supernovae (Stritzinger+, 2018)
J/ApJ/877/81 : The C3R2 survey: DR2 new sp. redshifts (Masters+, 2019)
J/ApJ/905/94 : Classif. for PS1-MDS SNe with SuperRAENN (Villar+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Transient name
11- 23 A13 --- Class Spectroscopic classification (1)
25- 32 F8.4 deg RAdeg Host Right Ascension, decimal degree (J2000)
34- 41 F8.4 deg DEdeg Host Declination, decimal degree (J2000)
43- 50 I8 d MJD [51633/57718]?=-2400000 Modified Julian Date of
observation (JD-2400000.5)
52- 55 A4 --- Tel Telescope ("MMT", "AAT", "WIYN", "SDSS" or "APO")
57- 61 F5.3 --- zf [0/2.77]? Final redshift
63- 67 F5.3 --- zRVSAO [0.005/1.25] RVSAO redshift
69- 70 I2 --- Nmatch [1/14] Number, template matches
72- 76 F5.2 --- RCC [0/69.3] Maximum cross-correlation score
--------------------------------------------------------------------------------
Note (1): Spectroscopic classification as follows:
SNIa = Type Ia supernova (699 occurrences)
SNII = Type II supernova (164 occurrences)
SNIIn = Type IIn supernova (47 occurrences)
SNIIb? = possible SN IIb (3 occurrences)
SLSN = Superluminous supernova (37 occurrences)
SNIbc (Ic) = (27 occurrences)
SNIbc (Ic-BL) = (5 occurrences)
SNIbc (Ib) = (5 occurrences)
Bad = (231 occurrences)
Bad (rise) = (3 occurrences)
VAR = (202 occurrences)
AGN = active galactic nuclei (19 occurrences)
QSO = (14 occurrences)
FELT = fast-evolving luminous transient (18 occurrences)
FELT (Bronze) = (7 occurrences)
TDE = tidal disruption event (2 occurrences)
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Transient name
11- 16 F6.4 --- z [0.035/2.32] Host galaxy redshift
18- 23 F6.4 mag E(B-V) [0.0034/0.12] Milky Way E(B-V) (G1)
25- 30 A6 --- PClass Photometric classification (1)
32- 36 F5.3 --- Conf [0.3/1] Classification confidence
38- 43 F6.1 --- chi2 [-687/801.5]? Reduced χ2 statistic (G2)
45- 48 F4.1 --- R [1/27.1] Maximum
Gelman & Rubin (1992StaSc...7..457G 1992StaSc...7..457G)
convergence statistic
50- 54 F5.3 --- pSLSN [0/1] Classification probability, SLSN
56- 60 F5.3 --- pSNII [0/0.973] Classification probability, SNII
62- 66 F5.3 --- pSNIIn [0/0.95] Classification probability, SNIIn
68- 72 F5.3 --- pSNIa [0/1] Classification probability, SNIa
74- 78 F5.3 --- pSNIbc [0/0.91] Classification probability, SNIbc
--------------------------------------------------------------------------------
Note (1): Photometric classification as follows:
SN Ia = 1259 occurrences
SN II = 521 occurrences
SN Ibc = 298 occurrences
SN IIn = 180 occurrences
SLSN = 57 occurrences
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Transient Name
11- 16 F6.4 --- z [0.0066/1.572] Transient Galaxy Redshift
18- 23 F6.4 mag E(B-V) [0.0059/0.13] Milky Way E(B-V) (G1)
25- 30 A6 --- SClass Spectroscopic Classification
32- 37 A6 --- PClass Photometric Classification
39- 43 F5.3 --- Conf [0.3/1] Classification confidence
45- 49 F5.1 --- chi2 [-33/388.5]? Reduced χ2 statistic (G2)
51- 54 F4.1 --- R [1/39.2] Maximum
Gelman & Rubin (1992StaSc...7..457G 1992StaSc...7..457G)
convergence statistic
56- 60 F5.3 --- pSLSN [0/0.99] Classification probability, SLSN
62- 66 F5.3 --- pSNII [0/0.982] Classification probability, SNII
68- 72 F5.3 --- pSNIIn [0/0.96] Classification probability, SNIIn
74- 78 F5.3 --- pSNIa [0/1] Classification probability, SNIa
80- 84 F5.3 --- pSNIbc [0/0.74] Classification probability, SNIbc
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Transient Name
11- 16 F6.4 --- z [0.053/1.4] Transient Redshift
18- 23 F6.4 mag E(B-V) [0.007/0.1] Milky Way E(B-V) (G1)
25- 36 A12 --- SClass Spectroscopic Classification
38- 43 A6 --- PClass Photometric Classification
45- 49 F5.3 --- Conf [0.4/0.9] Classification confidence
51- 53 F3.1 --- chi2 [0.9/6.2] Reduced χ2 statistic
55- 57 F3.1 --- R [1/3] Maximum Gelman & Rubin (1992StaSc...7..457G 1992StaSc...7..457G)
convergence statistic
59- 63 F5.3 --- pSLSN [0/0.853] Classification probability, SLSN
65- 69 F5.3 --- pSNII [0/0.83] Classification probability, SNII
71- 75 F5.3 --- pSNIIn [0/0.78] Classification probability, SNIIn
77- 81 F5.3 --- pSNIa [0.03/0.75] Classification probability, SNIa
83- 87 F5.3 --- pSNIbc [0/0.78] Classification probability, SNIbc
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Global notes:
Note (G1): E(B-V) from the Milky Way extinction maps of
Schlafly & Finkbeiner (2011ApJ...737..103S 2011ApJ...737..103S)
Note (G2): Rows where χ2 is null (blank) are where χ2 went
to infinity.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-Jul-2022