J/ApJ/922/21 Type Ia SN 2020nlb opt. photometry & spectra (Sand+, 2021)
Circumstellar medium constraints on the environment of two nearby type Ia
supernovae: SN 2017cbv and SN 2020nlb.
Sand D.J., Sarbadhicary S.K., Pellegrino C., Misra K., Dastidar R.,
Brown P.J., Itagaki K., Valenti S., Swift J.J., Andrews J.E.,
Bostroem K.A., Burke J., Chomiuk L., Dong Y., Galbany L., Graham M.L.,
Hiramatsu D., Howell D.A., Hsiao E.Y., Janzen D., Jencson J.E.,
Lundquist M.J., McCully C., Reichart D., Smith N., Wang L., Wyatt S.
<Astrophys. J., 922, 21 (2021)>
=2021ApJ...922...21S 2021ApJ...922...21S
ADC_Keywords: Supernovae; Photometry, UBVRI; Spectra, optical
Keywords: Type Ia supernovae ; Circumstellar matter
Abstract:
We present deep Chandra X-ray observations of two nearby Type Ia
supernovae, SN 2017cbv and SN 2020nlb, which reveal no X-ray emission
down to a luminosity LX≲5.3x1037 and ≲5.4x1037erg/s
(0.3-10keV), respectively, at ∼16-18 days after the explosion. With
these limits, we constrain the pre-explosion mass-loss rate of the
progenitor system to be dM/dt<7.2x10-9 and <9.7x10-9M☉/yr
for each (at a wind velocity vw=100km/s and a radius of R∼1016cm),
assuming any X-ray emission would originate from inverse Compton
emission from optical photons upscattered by the supernova shock. If
the supernova environment was a constant-density medium, we would find
a number density limit of nCSM<36 and <65cm-3, respectively. These
X-ray limits rule out all plausible symbiotic progenitor systems, as
well as large swathes of parameter space associated with the single
degenerate scenario, such as mass loss at the outer Lagrange point and
accretion winds. We also present late-time optical spectroscopy of
SN2020nlb, and set strong limits on any swept up hydrogen
(LHα<2.7x1037erg/s) and helium
(LHe,λ6678<2.7x1037erg/s) from a nondegenerate companion,
corresponding to MH≲0.7-2x10-3M☉ and MHe≲4x10-3M☉.
Radio observations of SN 2020nlb at 14.6 days after explosion also
yield a non-detection, ruling out most plausible symbiotic progenitor
systems. While we have doubled the sample of normal Type Ia supernovae
with deep X-ray limits, more observations are needed to sample the
full range of luminosities and subtypes of these explosions, and set
statistical constraints on their circumbinary environments.
Description:
SN 2020nlb was discovered on 2020 June 25.25 UT (MJD 59025.25) by the
Asteroid Terrestrial impact Last Alert System (ATLAS) survey. The last
non-detection from ATLAS was 2 days earlier (2020 June 23.28). The
field of SN 2020nlb was also monitored by the Itagaki Astronomical
Observatory's 0.35m telescope in Okayama, Japan, which obtained a
tighter non-detection epoch of 2020 June 24.57 (MJD 59024.57) before
also detecting the SN on 2020 June 26.56.
We display a UBVgri light curve of SN 2020nlb in the left panel of
Figure 1, taken with the 0.4 and 1.0m telescope network of Las Cumbres
Observatory as part of the Global Supernova Project.
An additional, high cadence data set was obtained by the 0.7m Thacher
Observatory in the g, r, i, z bands.
Observations from the Neil Gehrels Swift Observatory Ultra-Violet
Optical Telescope (UVOT) were also obtained.
In the right panel of Figure 1, we show a spectrum taken with the
FLOYDS robotic spectrograph at Faulkes Telescope North on 2020 July 12
06:32 UTC (+0.5 day with respect to B-band maximum).
An additional low resolution optical spectrum was obtained with the
Blue Channel spectrograph at the MMT on 2021 January 28 21:06 UTC
(+179 days), see Figure 4.
See Section 2.2.
The Swift XRT observed both SN 2017cbv and SN 2020nlb extensively. We
gathered Swift XRT data of SN 2017cbv taken between 2017 March 10.5
and April 15.46, corresponding to ∼1.5 and 37.5 days from our adopted
explosion epoch, with a total accumulated exposure time of 62.2ks.
A sequence of Swift XRT data was taken of SN 2020nlb, starting on
2020 June 25.76 UTC. We gathered all data taken through
2020 August 07.2 UTC (43days after our adopted explosion epoch), a
total of 27.5ks.
Deep X-ray follow-up of both SN 2017cbv and SN 2020nlb were obtained
with the Chandra X-ray Observatory under Director's Discretionary Time
proposals. Observations of SN 2017cbv began on 2017 March 27
(PI: Drout; Proposal 1850876; Obs ID 20055), and the total exposure
time was 51ks. Chandra observations of SN 2020nlb (PI: Sand;
Proposal 21508740; Obs ID 23314, 23315) 19 were split into two blocks
for a total exposure time of 75 ks. The first observation (totaling
63ks) began on 2020 July 09 23:58 (UT), while the second observation
(12ks) began ∼1.5days after the end of the first one on 2020 July 12
04:15.
See Section 3.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
12 25 24.17 +18 12 12.7 SN 2020nlb = ZTF20abijfqq
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1a.dat 28 85 Swift UVOT photometry of SN 2020nlb
fig1b.dat 35 199 Thacher Observatory optical photometry of SN 2020nlb
fig1c.dat 30 107 Las Cumbres Observatory optical photometry
of SN 2020nlb
fig1d.dat 20 3733 The FLOYDS +0.5 day spectrum of SN 2020nlb
fig4.dat 19 2708 Nebular-phase MMT/BCS spectrum of SN 2020nlb
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)
J/MNRAS/313/469 : Streaming motions of galaxy clusters. I. (Smith+, 2000)
J/ApJ/655/144 : ACS Virgo Cluster Survey. XIII. (Mei+, 2007)
J/MNRAS/377/1531 : Optical & IR photometry of SN 2004eo (Pastorello+, 2007)
J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)
J/AJ/143/126 : Spectroscopy of nearby Type Ia supernovae (Blondin+, 2012)
J/ApJ/749/18 : Swift/UVOT observations of 12 nearby SN-Ia (Brown+, 2012)
J/ApJ/748/L29 : SN Ia supernovae observed by Swift/XRT (Russell+, 2012)
J/ApJ/773/53 : Type Ia SNe spectroscopy by the CSP (Folatelli+, 2013)
J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)
J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJ/853/62 : Opt. and NIR spectra and LCs of SN2016ija (Tartaglia+, 2018)
J/ApJ/870/L1 : K2 obs. of type Ia supernova SN 2018oh (Dimitriadis+, 2019)
J/A+A/627/A174 : Early light curve of SN 2013gy (Holmbo+, 2019)
J/ApJ/870/13 : K2 LC alternative analysis of ASASSN-18bt (Shappee+, 2019)
J/ApJ/895/118 : Opt. & NIR photometry of 2 Ia type supernovae (Burns+, 2020)
J/ApJ/898/56 : UVOT, ZTF gri LCs & spectra of SN Ia 2019yvq (Miller+, 2020)
J/ApJ/897/159 : Type Ia SN 2019ein UBVgri photometry (Pellegrino+, 2020)
J/ApJ/904/14 : Optical and NIR observation of SN (Ia) 2017cbv (Wang+, 2020)
J/ApJ/914/50 : Opt. phot. & GMOS & NIRES sp. of SN2019yvq (Tucker+, 2021)
Byte-by-byte Description of file: fig1a.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Filt Filter (UBV, UVM2, UVW1, UVW2)
6- 15 F10.4 d MJD [59025.7/59068.3] Modified Julian Date
17- 22 F6.3 mag mag [11.77/19.02] Apparent Vega magnitude in Filt
24- 28 F5.3 mag e_mag [0.029/0.4] Uncertainty in mag
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Byte-by-byte Description of file: fig1b.dat
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Bytes Format Units Label Explanations
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1 A1 --- Filt [griz] Filter
3- 20 F18.10 d BJD Barycentric Julian Date
22- 28 F7.4 mag mag [12/16.6] Apparent AB magnitude in Filt
30- 35 F6.4 mag e_mag [0/0.2] Uncertainty in mag
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Byte-by-byte Description of file: fig1c.dat
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Bytes Format Units Label Explanations
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1 A1 --- Filt [UBVgri] Filter
3- 15 F13.5 d JD Julian Date
17- 23 F7.4 mag mag [11.93/16.7] Apparent magnitude in Filt (1)
25- 30 F6.4 mag e_mag [0.008/0.6] Uncertainty in mag
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Note (1): Vega system for UBV and AB for gri.
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Byte-by-byte Description of file: fig1d.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 0.1nm lambda [3500.6/10000.5] Wavelength; Angstroms
12- 20 E9.3 cW/m2/nm Flux [4.7e-15/1.5e-13] Flux density; erg/s/cm2/Å
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Byte-by-byte Description of file: fig4.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 0.1nm lambda [3735.7/9013.7] Wavelength; Angstroms
11- 19 E9.3 cW/m2/nm Flux [1.6e-19/5.1e-16]?=0 Flux density;
in erg/s/cm2/Å units
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 21-Mar-2023