J/ApJ/898/56 UVOT, ZTF gri LCs and spectra of the SN Ia 2019yvq (Miller+, 2020)
The spectacular ultraviolet flash from the peculiar Type Ia supernova 2019yvq.
Miller A.A., Magee M.R., Polin A., Maguire K., Zimmerman E., Yao Y.,
Sollerman J., Schulze S., Perley D.A., Kromer M., Dhawan S., Bulla M.,
Andreoni I., Bellm E.C., De K., Dekany R., Delacroix A., Fremling C.,
Gal-Yam A., Goldstein D.A., Golkhou V.Z., Goobar A., Graham M.J., Irani I.,
Kasliwal M.M., Kaye S., Kim Y.-L., Laher R.R., Mahabal A.A., Masci F.J.,
Nugent P.E., Ofek E., Phinney E.S., Prentice S.J., Riddle R., Rigault M.,
Rusholme B., Schweyer T., Shupe D.L., Soumagnac M.T., Terreran G.,
Walters R., Yan L., Zolkower J., Kulkarni S.R.
<Astrophys. J., 898, 56 (2020)>
=2020ApJ...898...56M 2020ApJ...898...56M
ADC_Keywords: Supernovae; Photometry, ugriz; Surveys; Photometry, ultraviolet;
Spectroscopy
Keywords: Surveys ; Supernovae ; Type Ia supernovae ; White dwarf stars ;
Observational astronomy
Abstract:
Early observations of Type Ia supernovae (SNe Ia) provide essential
clues for understanding the progenitor system that gave rise to the
terminal thermonuclear explosion. We present exquisite observations of
SN 2019yvq, the second observed SN Ia, after iPTF 14atg, to display an
early flash of emission in the ultraviolet (UV) and optical. Our
analysis finds that SN 2019yvq was unusual, even when ignoring the
initial flash, in that it was moderately underluminous for an SN Ia
(Mg~-18.5mag at peak) yet featured very high absorption velocities
(v∼15000km/s for SiIIλ6355 at peak). We find that many of the
observational features of SN 2019yvq, aside from the flash, can be
explained if the explosive yield of radioactive 56Ni is relatively low
(we measure M56Ni=0.31±0.05M☉) and it and other iron-group
elements are concentrated in the innermost layers of the ejecta. To
explain both the UV/optical flash and peak properties of SN 2019yvq we
consider four different models: interaction between the SN ejecta and
a nondegenerate companion, extended clumps of 56Ni in the outer
ejecta, a double-detonation explosion, and the violent merger of two
white dwarfs. Each of these models has shortcomings when compared to
the observations; it is clear additional tuning is required to better
match SN 2019yvq. In closing, we predict that the nebular spectra of
SN 2019yvq will feature either H or He emission, if the ejecta
collided with a companion, strong [CaII] emission, if it was a double
detonation, or narrow [OI] emission, if it was due to a violent merger.
Description:
The Zwicky Transient Facility (ZTF) simultaneously conducts multiple
time-domain surveys using the ZTF camera on the the Palomar Oschin
Schmidt 48 inch (P48) telescope. SN 2019yvq was first detected by ZTF
on 2019 December 29.46, as part of the ZTF public survey
(see Bellm+ 2019PASP..131f8003B 2019PASP..131f8003B). Continued monitoring with ZTF, and
follow-up with other telescopes, confirmed a spectacular decline in
the early emission from SN 2019yvq (Figure 1).
The field of SN 2019yvq was additionally observed by ZTF with nearly a
nightly cadence as part of the ZTF partnership Uniform Depth Survey
(ZUDS; D. Goldstein et al. 2020, in preparation). Using images
obtained as part of the ZUDS program, we perform forced point-spread
function (PSF) photometry at the location of SN 2019yvq following the
procedure described in Yao+ (2019, J/ApJ/886/152).
UV observations of SN 2019yvq were obtained with the UVOT onboard the
Neil Gehrels Swift Observatory.
We obtained a first spectrum, ∼1.8 days after the initial ZTF
detection with the SPectrograph for the Rapid Acquisition of
Transients (SPRAT) on the 2m Liverpool Telescope (LT). Further
spectroscopy was obtained with a variety of telescopes, including: the
Spectral Energy Density machine (SEDM) on the Palomar 60 inch
telescope (P60), Binospec on the 6.5m MMT telescope, the
Low-Resolution Imaging Spectrometer (LRIS) on the 10m Keck I
telescope, the Andalucia Faint Object Spectrograph and Camera (ALFOSC)
on the 2.5m Nordic Optical Telescope (NOT), and the Double
Spectrograph (DBSP) on the Palomar 200 in Hale Telescope.
25 observations have been made spanning 2019 Dec 31 to 2020 March 22
(see Table 3).
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
12 27 21.85 +64 47 59.8 SN 2019yvq = ZTF19adcecwu
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 29 435 ZTF P48 photometry of SN 2019yvq
table2.dat 28 57 UVOT photometry of SN 2019yvq
table3.dat 100 25 Spectroscopic observations of SN 2019yvq
sp/* . 25 Individual spectrum in ASCII format
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See also:
J/MNRAS/377/1531 : Optical & IR photometry of SN 2004eo (Pastorello+, 2007)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
J/AJ/139/120 : Low-redshift Type-Ia supernovae (Folatelli+, 2010)
J/MNRAS/410/585 : SN 2009dc BVRI light curves (Silverman+, 2011)
J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
J/AJ/143/126 : Spectroscopy of 462 nearby Type Ia SNe (Blondin+, 2012)
J/ApJ/749/18 : Swift/UVOT observations of 12 nearby SN-Ia (Brown+, 2012)
J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)
J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)
J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)
J/ApJ/836/232 : Swift-UVOT obs. analysis of 29 SNe Ia (Brown+, 2017)
J/MNRAS/464/2672 : ASAS-SN bright supernova catalog 2013-2014 (Holoien+, 2017)
J/AJ/154/211 : The CSP (DR3): photometry of low-z SNeIa (Krisciunas+, 2017)
J/ApJ/877/152 : UV to NIR light curves of type Ia SN 2017erp (Brown+, 2019)
J/ApJ/870/L1 : K2 obs. of type Ia supernova SN 2018oh (Dimitriadis+, 2019)
J/ApJ/870/13 : K2 LC alternative analysis of ASASSN-18bt (Shappee+, 2019)
J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)
J/ApJ/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 2020)
J/A+A/634/A37 : TURTLS Light curves of 56Ni distributions (Magee+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d MJD [58846.4/58999.3] Epoch, Modified Julian Date
(JD-2400000.5)
12- 18 F7.2 uJy Flux [66.5/5348.1] Flux in Filt
20- 24 F5.2 uJy e_Flux [2.68/91.89] Uncertainty in Flux
26- 29 A4 --- Filt Filter (gztf, iztf or rztf) (1)
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Note (1): Observed fluxes in the ZTF passbands, no correction for reddening
has been applied. Due to poor observing conditions, SN 2019yvq is not
detected in one gZTF and one iZTF image from 2020 March 09, and we
therefore do not provide a flux measurement for those epochs.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d MJD [58846.8/58907] Epoch, Modified Julian Date
(JD-2400000.5)
12- 17 F6.2 uJy Flux [4.04/457.9] Flux in Filt
19- 23 F5.2 uJy e_Flux [2.9/30.8] Uncertainty in Flux
25- 28 A4 --- Filt Filter (uvm2, uvw1 or uvw2) (1)
--------------------------------------------------------------------------------
Note (1): Host-subtracted fluxes in the UVOT passbands, no correction for
reddening has been applied. Epochs with S/N<3 are shown as upper limits
in Figure 1.
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 "Y/M/D" Obs.date Observing date (ISO 8601);
column added by CDS
12- 19 A8 "h:m:s" Obs.time Observing time (ISO 8601);
column added by CDS
21- 28 F8.2 d MJD [58848.2/58930.5] Modified Julian Date
30- 34 F5.1 d Phase [-14.9/66.5] Phase relative to TB,max in
the SN rest frame (1)
36- 47 A12 --- Tel Telescope/Instrument
49- 52 I4 --- R [100/4000] Resolution Δλ/λ
for the central region of the spectrum
54- 63 A10 0.1nm Range Wavelength range in Å units
65- 68 F4.2 --- AirMass [1.19/1.88] Airmass
70-100 A31 --- FileName Name of the spectrum file; column added by CDS
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Note (1): The time of B-band maximum, TB,max, is 58863.33±0.21 MJD.
See Section 2.2.
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Byte-by-byte Description of file: sp/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 0.1nm lambda [3064.5/10305.5] Wavelength in Angstrom units
10- 31 E22.6 --- Flux [-0.4/1212.5]? Relative Flux
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 17-Nov-2021