J/ApJ/919/49 SNIa SN2017fgc follow-up phot. & spectra (Zeng+, 2021)
SN 2017fgc: a fast-expanding type Ia supernova exploded in massive shell galaxy
NGC 474.
Zeng X., Wang X., Esamdin A., Pellegrino C., Burke J., Stahl B.E., Zheng W.,
Filippenko A.V., Howell D.A., Sand D.J., Valenti S., Mo J., Xi G., Liu J.,
Zhang J., Li W., Iskandar A., Zhang M., Lin H., Sai H., Xiang D., Wei P.,
Zhang T., Reichart D.E., Brink T.G., McCully C., Hiramatsu D.,
Hosseinzadeh G., Jeffers B.T., Ross T.W., Stegman S., Wang L., Zhang J.,
Ma S.
<Astrophys. J., 919, 49 (2021)>
=2021ApJ...919...49Z 2021ApJ...919...49Z
ADC_Keywords: Supernovae; Photometry, UBVRI; Spectra, optical
Keywords: Supernovae ; Type Ia supernovae
Abstract:
We present extensive optical photometric and spectroscopic
observations of the high-velocity (HV) Type Ia supernova (SN Ia)
2017fgc, covering the phase from ∼12 days before to ∼389 days after
maximum brightness. SN 2017fgc is similar to normal SNe Ia, with an
absolute peak magnitude of MmaxB~-19.32±0.13mag and a post-peak
decline of Δm15(B)=1.05±0.07mag. Its peak bolometric
luminosity is derived as (1.32±0.13)x1043erg/s, corresponding to a
56Ni mass of 0.51±0.03M☉. The light curves of SN 2017fgc are
found to exhibit excess emission in the UBV bands in the early nebular
phase and pronounced secondary shoulder/maximum features in the RrIi
bands. Its spectral evolution is similar to that of HV SNe Ia, with a
maximum-light SiII velocity of 15000±150km/s and a post-peak
velocity gradient of ∼120±10km/s/day. The FeII and MgII lines
blended near 4300Å and the FeII, SiII, and FeIII lines blended near
4800Å are obviously stronger than those of normal SNe Ia.
Inspecting a large sample reveals that the strength of the two blends
in the spectra, and the secondary peak in the i/r-band light curves,
are found to be positively correlated with the maximum-light SiII
velocity. Such correlations indicate that HV SNe Ia may experience
more complete burning in the ejecta and/or that their progenitors have
higher metallicity. Examining the birthplace environment of SN 2017fgc
suggests that it likely arose from a stellar environment with young
and high-metallicity populations.
Description:
SN 2017fgc was discovered at RAJ2000=01:20:14.440,DEJ2000=03:24:09.96
on 2017 July 9.29 by the Distance Less Than 40Mpc (DLT40;
Tartaglia+ 2018, J/ApJ/853/62).
Our photometric observations of SN 2017fgc were obtained with several
telescopes, including the 0.8m Tsinghua-NAOC telescope (TNT), the Las
Cumbres Observatory (LCO) Telescope network, the 0.76m Katzman
Automatic Imaging Telescope (KAIT) at Lick Observatory, and the 1m
Nickel reflector at Lick Observatory.
The TNT and the Nickel telescope monitored SN 2017fgc in the BVRI
bands, KAIT observed it in the BVRI and Clear bands, and the LCO 1m
telescopes sampled the light curves in the UBVgri bands.
A total of 38 low-resolution spectra were obtained for SN 2017fgc with
different instruments, including the FLOYDS spectrographs mounted on
the LCO 2m Faulkes Telescope North and South (FTN and FTS), the BFOSC
mounted on the Xinglong 2.16m telescope (XLT), the YFOSC on the
Lijiang 2.4m telescope (LJT) of Yunnan Astronomical Observatories, and
the Kast spectrograph on the Lick 3m Shane telescope. Three additional
spectra of SN 2017fgc were obtained with XSHOOTER mounted on the ESO
Very Large Telescope (VLT), at t~+149.7days, +383.9days, and 388.9days
during ESO programs 0101.D-0242(A) and 0101.D-0443(A). The journal of
spectroscopic observations is presented in Table 3.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
01 20 14.43 +03 24 09.9 SN 2017fgc = DLT 17bx
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 140 151 Photometric observations of SN2017fgc
by ground-based telescopes
table3.dat 74 38 Spectroscopic observations of SN 2017fgc
table4.dat 36 120 DLT40 photometry of SN2017fgc in the clear band
sp/* . 38 *Individual spectrum in ASCII format
(data behind Figure 10)
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Note on sp/*: Each spectra file has three columns which represents lambda,
flux and flux error, respectively. The spectra are not de-reddened.
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See also:
II/183 : UBVRI Photometric Standards (Landolt 1992)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/ApJ/645/488 : SN type Ia luminosities (Wang+, 2006)
J/MNRAS/377/1531 : Optical & IR photometry of SN 2004eo (Pastorello+, 2007)
J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)
J/ApJS/190/418 : Light curves for 165 SNe (Ganeshalingam+, 2010)
J/A+A/523/A7 : Light curves of type Ia supernovae in SNLS (Guy+, 2010)
J/PASP/122/1 : BVRI light curves of SN 2007gi (Zhang+, 2010)
J/MNRAS/413/813 : ATLAS3D project. I. (Cappellari+, 2011)
J/MNRAS/412/1441 : SNe luminosity functions (Li+, 2011)
J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
J/MNRAS/410/1262 : Supernova Legacy Survey. Type Ia SNe (Walker+, 2011)
J/AJ/143/126 : Spectroscopy of 462 nearby Type Ia SNe (Blondin+, 2012)
J/ApJS/200/12 : CfA4: light curves for 94 type Ia SNe (Hicken+, 2012)
J/MNRAS/425/1819 : Berkeley supernova Ia program. II. (Silverman+, 2012)
J/ApJ/773/53 : Type Ia SNe spectroscopy by the CSP (Folatelli+, 2013)
J/other/NewA/20.30 : BVRI light curves of 3 SN (Munari+, 2013)
J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)
J/other/Sci/340.170 : Classifications of 188 SNe Ia (Wang+, 2013)
J/A+A/568/A22 : Joint analysis of SDSS-II & SNLS SNe Ia (Betoule+, 2014)
J/MNRAS/448/2766 : Strong lines in the opt/NIR for SN2002bo (Blondin+, 2015)
J/MNRAS/446/120 : ATLAS3D project. XXIX (Duc+, 2015)
J/ApJS/220/20 : Si and Ca high-velocity features in SNe Ia (Zhao+, 2015)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJ/835/123 : Globular clusters in NGC 474 from CFHT obs. (Lim+, 2017)
J/ApJ/869/56 : Updated calibration of CSP-I SNe Ia sample (Burns+, 2018)
J/ApJ/859/101 : The supernovae Ia Pantheon sample (Scolnic+, 2018)
J/ApJ/853/62 : Opt. & NIR spectra & LCs of SN2016ija (Tartaglia+, 2018)
J/ApJ/882/120 : CfA, CSP, BSP & LOSS sp. & phot. of SNe Ia (Wang+, 2019)
J/ApJ/893/143 : UBVRIJHK & sp. obs. of SN 2019ein (Kawabata+, 2020)
J/ApJ/909/176 : SN2017hpa carbon-rich type Ia LCs and sp. (Zeng+, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [57947.1/58164.2] Modified Julian Date of obs
(JD-2400000.5)
10- 16 F7.2 d Epoch [-12.3/204.72] Days relative to MJD=57959.4
18- 23 F6.3 mag Umag [13.52/18.92]? Johnson U band AB magnitude
25- 29 F5.3 mag e_Umag [0.04/0.8]? Uncertainty in Umag
31- 36 F6.3 mag Bmag [13.79/18.66]? Johnson B band AB magnitude
38- 42 F5.3 mag e_Bmag [0.019/1]? Uncertainty in Bmag
44- 49 F6.3 mag Vmag [13.5/18.66]? Johnson V band AB magnitude
51- 55 F5.3 mag e_Vmag [0.017/0.2]? Uncertainty in Vmag
57- 62 F6.3 mag Rmag [13.52/19.69]? Johnson R band AB magnitude
64- 68 F5.3 mag e_Rmag [0.02/0.5]? Uncertainty in Rmag
70- 75 F6.3 mag Imag [13.88/19.35]? Johnson I band AB magnitude
77- 81 F5.3 mag e_Imag [0.029/0.4]? Uncertainty in Imag
83- 88 F6.3 mag gmag [13.68/18.01]? Sloan g band AB magnitude
90- 94 F5.3 mag e_gmag [0.015/0.12]? Uncertainty in gmag
96-101 F6.3 mag rmag [13.54/19.2]? Sloan r band AB magnitude
103-107 F5.3 mag e_rmag [0.015/0.2]? Uncertainty in rmag
109-114 F6.3 mag imag [14.31/19.21]? Sloan i band AB magnitude
116-120 F5.3 mag e_imag [0.02/0.2]? Uncertainty in imag
122-127 F6.3 mag Cmag [13.58/18.81]? Clear-band AB magnitude;
calibrated to standard Landolt R-band
129-133 F5.3 mag e_Cmag [0.025/0.7]? Uncertainty in Cmag
135-140 A6 --- Tel Telescope used (1)
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Note (1): Telescope and bandpass calibration information as follows:
KAIT4 = 0.76m Katzman Automatic Imaging Telescope at Lick Observatory
(87 occurrences).
Calibrated to the Johnson UBVRI while Clear data were calibrated
to the standard Landolt R-band magnitudes.
LCO = Las Cumbres Observatory (LCO) Telescope network (42 occurrences).
UBV are calibrated to the Johnson system while gri magnitudes are
calibrated using the SDSS Dr12 catalog.
Nickel = 1m Nickel reflector at Lick Observatory (7 occurrences).
Calibrated to Johnson UBVRI.
TNT = 0.8m Tsinghua-NAOC telescope (15 occurrences).
Calibrated to Johnson UBVRI.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [57947.7/58348.3] Modified Julian Date
10- 15 F6.1 d Epoch [-11.7/388.9] Days relative to the epoch of
B-band maximum brightness, MJD=57959.4
17- 20 I4 0.1nm lam1 [2990/5711] Lower range of wavelength in Å
22- 26 I5 0.1nm lam2 [6963/24790] Upper range of wavelength in Å
28- 37 A10 --- Tel Telescope (1)
39- 74 A36 --- FileName Name of the ASCII file in subdirectory "sp";
column added by CDS
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Note (1): Telescope as follows:
LCO = the FLOYDS spectrographs mounted on the LCO 2m Faulkes
Telescope North and South (21 occurrences)
Lick 3m = the Kast spectrograph on the Lick 3m Shane telescope
(11 occurrences)
ESO public = XSHOOTER mounted on the ESO Very Large Telescope during ESO
programs 0101.D-0242(A) and 0101.D-0443(A) (2 occurrences)
XLT = the BFOSC mounted on the Xinglong 2.16m telescope (2 occurrences)
LJT = the YFOSC on the Lijiang 2.4m telescope of Yunnan Astronomical
Observatories (1 occurrence)
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.1 d MJD [57942.3/58124.5] Modified Julian Date of obs
(JD-2400000.5)
9- 13 F5.1 d Epoch [-17.1/165.1] Days relative to MJD=57959.4
15- 20 F6.3 mag Cmag [13.65/19.2]? Clear-band AB magnitude;
calibrated to R-band
22- 26 F5.3 mag e_Cmag [0.016/0.09]? Uncertainty in Cmag
28- 36 A9 --- Tel Distance Less Than 40 Telescope (DLT40;
Tartaglia+ 2018, J/ApJ/853/62) telescope
used ("Prompt5" or "Meckering")
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-Jan-2023