J/ApJ/930/57 Multiwavelength monitoring of the type Ib SN 2014C (Thomas+, 2022)
Seven years of SN 2014C: a multiwavelength synthesis of an extraordinary
supernova.
Thomas B.P., Wheeler J.C., Dwarkadas V.V., Stockdale C., Vinko J.,
Pooley D., Xu Y., Zeimann G., MacQueen P.
<Astrophys. J., 930, 57 (2022)>
=2022ApJ...930...57T 2022ApJ...930...57T
ADC_Keywords: Supernovae; Spectra, optical; X-ray sources; Radio sources;
Photometry, infrared
Keywords: Supernovae ; Type Ib supernovae ; Type II supernovae ;
Circumstellar matter ; Circumstellar disks ; Circumstellar shells ;
X-ray transient sources ; Radio transient sources
Abstract:
SN 2014C was originally classified as a Type Ib supernova, but at
phase φ=127d, post-explosion strong Hα emission was
observed. SN 2014C has since been observed in radio, infrared, optical
and X-ray bands. Here we present new optical spectroscopic and
photometric data spanning φ=947-2494d post-explosion. We address
the evolution of the broadened Hα emission line, as well as
broad [OIII] emission and other lines. We also conduct a parallel
analysis of all publicly available multiwavelength data. From our
spectra, we find a nearly constant Hα FWHM velocity width of
∼2000km/s that is significantly lower than that of other broadened
atomic transitions (∼3000-7000km/s) present in our spectra
([OI]λ6300; [OIII]λλ4959,5007; HeIλ7065;
[CaII]λλ7291,7324). The late radio data demand a fast
forward shock (∼10000km/s at φ=1700d) in rarified matter that
contrasts with the modest velocity of the Hα. We propose that
the infrared flux originates from a toroidal-like structure of
hydrogen surrounding the progenitor system, while later emission at
other wavelengths (radio, X-ray) likely originates predominantly from
the reverse shock in the ejecta and the forward shock in the
quasi-spherical progenitor He-wind. We propose that the Hα
emission arises in the boundary layer between the ejecta and torus. We
also consider the possible roles of a pulsar and a binary companion.
Description:
We utilize the Direct Imaging Auxiliary Functions Instrument (DIAFI)
imager on the Harlan J. Smith (HJS) 2.7m telescope at McDonald
Observatory since 2014 February. See Section 2.1.
The spectra and IFU images of SN 2014C reported here were obtained
with LRS2 on the 10m Hobby-Eberly Telescope (HET). LRS2 comprises two
IFU spectrographs separated by 100" on sky: LRS2-B (3650-6950Å) and
LRS2-R (6450-10500Å). See Section 2.2.
The average resolving power of our LRS2 spectrograph is R∼1500. We
acquired nine spectra of SN 2014C with our HET/LRS2 IFU setup from
2016 August 6 through to 2020 November 5 corresponding to phases
947-2493 days after first light. See Section 2.3.
The spatial and spectral resolution of the Chandra X-ray Observatory
(CXO) allows the position and emission lines of SN 2014C to be
resolved. Chandra observations were performed with the Advanced CCD
Imaging Spectrometer S-array instrument on Chandra, starting from 2014
November (φ=35days). See Section 3.3.
SN 2014C was observed by the FPMA/B instruments on NuSTAR nine times
between 2015 and 2020. See Section 3.4.
We made a new X-band radio observation of SN 2014C with the VLA in
the A configuration on 2019 August 31 that corresponds to phase
φ=2063d since first light. See Section 4.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
22 37 05.59 +34 24 31.8 SN 2014C = SPIRITS14aom
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 64 15 New data of SN 2014C
fig3.dat 47 45741 The nine HET/LRS2-R optical spectra of SN 2014C
fig10.dat 56 218 Light curves of SN 2014C at optical, X-ray,
infrared, and radio wavelengths
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See also:
J/MNRAS/412/1441 : SNe luminosity functions (Li+, 2011)
J/MNRAS/449/1876 : Photometric observations of SN PTF11iqb (Smith+, 2015)
J/ApJ/887/75 : NIR sp. of SN 2014C 1-5yr post-explosion (Tinyanont+, 2019)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Date Date of observation (UT)
12- 15 I4 --- Epoch [505/2494] Observation epoch; rest-frame days
17- 26 A10 --- Tel Telescope
28- 41 A14 --- Band Bandpass
43 A1 --- f_Band Flag on Band (1)
45- 49 F5.3 10+31W Lum [0.28/8.8] Luminosity in 1038erg/s
51- 54 F4.2 10+31W e_Lum [0.15/2]? Lower uncertainty on Lum
56- 59 F4.2 10+31W E_Lum [0.2/4]? Upper uncertainty on Lum
61- 64 I4 s Exp [142/3600] Exposure time
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Note (1): Luminosity was derived via Gaussian decompositions to the broadened
Hα spectral profile. These correspond to luminosities of the
broadened Hα component only.
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Byte-by-byte Description of file: fig3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 yr Obs.Y [2016/2020] Year of the observation
6- 7 I2 "month" Obs.M Month of the observation
9- 10 I2 d Obs.D Day of the observation
12- 15 I4 d Epoch [947/2494] Observation epoch; rest-frame days
17- 26 E10.4 0.1nm lambda [3640/10500] Wavelength; Angstroms
28- 37 E10.3 cW/m2/nm Flux [-2e-15/7e-15] Flux density;
erg/s/cm2/Angstroms (1)
39- 47 E9.3 cW/m2/nm e_Flux [0/5.5e-15] Uncertainty in Flux
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Note (1): Spectra have been fully wavelength- and flux-calibrated;
see Appendix 1 and Section 2.2 for details. Spectra have also been
corrected for MW dust extinction.
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Byte-by-byte Description of file: fig10.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Inst Instrument (1)
12- 21 A10 --- Band Wavelength band identifiers
23- 26 I4 d Epoch [12/2494] Observation epoch; rest-frame days
from discovery (2013 December 30)
28- 36 E9.3 10-7W Lum [1.45e+35/9.1e+40] Luminosity; erg/s
38- 46 E9.3 10-7W e_Lum [1.9e+34/8e+39]? Lower uncertainty in Lum
48- 56 E9.3 10-7W E_Lum [1.9e+34/8e+39]? Upper uncertainty in Lum
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Note (1): Instrument as follows:
AMI = the Arcminute Microkelvin Imager (AMI) Large Array at 15.7GHz
from Anderson+ 2017MNRAS.466.3648A 2017MNRAS.466.3648A (81 occurrences)
LRS2 = the Low-Resolution Spectrograph 2 on HET; this work
(PI: Wheeler; 36 occurrences)
Spitzer = Spitzer/IRAC from Tinyanont+ 2019, J/ApJ/887/75 (32 occurrences)
JVLA = Jansky Very Large Array at 4.9GHz from
Bietenholz+ 2021MNRAS.502.1694B 2021MNRAS.502.1694B (25 occurrences)
P200 = Palomar Observatory WIRC from
Tinyanont+ 2019, J/ApJ/887/75 (12 occurrences)
CXO+NuSTAR = CXO and the Nuclear Spectroscopic Telescope Array; this work
(PI: Margutti; 10 occurrences)
VLBA = NRAO Very Long Baseline Array
from Bietenholz+ 2018MNRAS.475.1756B 2018MNRAS.475.1756B (5 occurrences)
HJS = HJS/DIAFI from this work (PI: Wheeler; 5 occurrences)
eMerlin = from Anderson+ 2017MNRAS.466.3648A 2017MNRAS.466.3648A (4 occurrences)
NOT = NOT/NOTCam from Tinyanont+ 2019ApJ...887...75T 2019ApJ...887...75T (3 occurrences)
VLA = VLA at 15.1GHz from Bietenholz+ 2021MNRAS.502.1694B 2021MNRAS.502.1694B or
at 9GHz from this work (PI: Stockdale) (2 occurrences)
Gemini = Gemini/NIRI from Tinyanont+ 2019, J/ApJ/887/75 (2 occurrences)
Swift = Swift/XRT from Margutti+ 2017ApJ...835..140M 2017ApJ...835..140M (1 occurrence)
See Table 1 in Section 1.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Mar-2024