J/ApJ/920/127 AT 2019qyl UV-to-IR photometry and spectroscopy (Jencson+, 2021)
AT 2019qyl in NGC 300: internal collisions in the early outflow from a very fast
nova in a symbiotic binary.
Jencson J.E., Andrews J.E., Bond H.E., Karambelkar V., Sand D.J.,
van Dyk S.D., Blagorodnova N., Boyer M.L., Kasliwal M.M., Lau R.M.,
Mohamed S., Williams R., Whitelock P.A., Amaro R.C., Bostroem K.A.,
Dong Y., Lundquist M.J., Valenti S., Wyatt S.D., Burke J., De K.,
Jha S.W., Johansson J., Rojas-Bravo C., Coulter D.A., Foley R.J.,
Gehrz R.D., Haislip J., Hiramatsu D., Howell D.A., Kilpatrick C.D.,
Masci F.J., McCully C., Ngeow C.-C., Pan Y.-C., Pellegrino C., Piro A.L.,
Kouprianov V., Reichart D.E., Rest A., Rest S., Smith N.
<Astrophys. J., 920, 127 (2021)>
=2021ApJ...920..127J 2021ApJ...920..127J
ADC_Keywords: Novae; Photometry, ugriz; Photometry, ultraviolet;
Spectra, optical; Spectra, infrared
Keywords: Novae ; Symbiotic binary stars ; Recurrent novae ; White dwarf stars ;
Asymptotic giant branch stars ; Spectroscopy
Abstract:
Nova eruptions, thermonuclear explosions on the surfaces of white
dwarfs (WDs), are now recognized to be among the most common
shock-powered astrophysical transients. We present the early discovery
and rapid ultraviolet (UV), optical, and infrared (IR) temporal
development of AT 2019qyl, a recent nova in the nearby Sculptor Group
galaxy NGC 300. The light curve shows a rapid rise lasting ≲1day,
reaching a peak absolute magnitude of MV=-9.2mag and a very fast
decline, fading by 2mag over 3.5days. A steep dropoff in the light
curves after 71days and the rapid decline timescale suggest a low-mass
ejection from a massive WD with MWD≳1.2M☉. We present an
unprecedented view of the early spectroscopic evolution of such an
event. Three spectra prior to the peak reveal a complex,
multicomponent outflow giving rise to internal collisions and shocks
in the ejecta of an He/N-class nova. We identify a coincident
IR-variable counterpart in the extensive preeruption coverage of the
transient location and infer the presence of a symbiotic progenitor
system with an O-rich asymptotic-giant-branch donor star, as well as
evidence for an earlier UV-bright outburst in 2014. We suggest that AT
2019qyl is analogous to the subset of Galactic recurrent novae with
red-giant companions such as RS Oph and other embedded nova systems
like V407 Cyg. Our observations provide new evidence that internal
shocks between multiple, distinct outflow components likely contribute
to the generation of the shock-powered emission from such systems.
Description:
AT 2019qyl was discovered on UT 2019 September 26.21 (MJD 58752.21) by
the Distance <40Mpc subday-cadence SN search (DLT40; see
Tartaglia+ 2018, J/ApJ/853/62).
After the initial discovery and confirmation of AT 2019qyl, we took a
sequence of PROMPT5 images of the field over the next 4.3hr from CTIO.
The DLT40 team also triggered a rapid-response program with the Neil
Gehrels Swift Observatory in place to acquire high-cadence early UV
light curves of nearby transients, with the first data arriving ∼4hr
after discovery.
We obtained a sequence of images with the DLT40 PROMPT5 0.4-m
telescope at CTIO. The PROMPT5 telescope has no filter ("Open"), which
we calibrate to the r band. Immediately after discovery, we began an
intense photometric campaign with the Las Cumbres Observatory (LCO)
global telescope network in the UBVgri bands with the Sinistro cameras
on the 1m telescopes at CTIO (Chile), Siding Spring (Australia), and
Sutherland (South Africa). These data were taken as part of the Global
Supernova Project (GSP), as well as PI-led programs (grizs ; OPTICON
19B-053; PI N. Blagorodnova).
The Swope 1m telescope at Las Campanas Observatory (LCO) was used for
uBVgri observations. BVgri imaging was also taken with the Lulin
One-meter telescope in Taiwan.
UV and optical images were obtained during the early portion of the
light curve with the Ultraviolet/Optical telescope (UVOT) on board
Swift. The data were downloaded from the NASA Swift Data Archive.
The location of AT2019qyl was multiply imaged with the Infrared Array
Camera (IRAC) on board the Spitzer Space Telescope in the 3.6 and
4.5um imaging channels ([3.6] and [4.5]) between 2014 and the end of
2019 during regular monitoring of NGC300 by the SPitzer Infrared
Intensive Transients Survey (SPIRITS; PI: M. Kasliwal; PIDs 10136,
11063, 13053, and 14089) and in observations targeting the
ultraluminous X-ray source NGC300 ULX1 (PI: R. Lau; PID 14270).
We executed ToO observations with the Hubble Space Telescope (HST)
Wide Field Camera 3 (WFC3) UVIS channel in subarray mode in F555W
(23 frames, 690s total exposure; PI S. Van Dyk; PID GO-15151) on
2020 January 26.06 with the primary goal of obtaining a precise
position for AT 2019qyl in comparison with archival imaging.
We obtained a sequence of five optical spectra between
2019 September 26.29 and 2019 October 4.04, spanning from 1.9hr to 8d
after discovery. Our earliest spectrum was obtained with the Gemini
Multi-Object Spectrographs (GMOS) on the 8.1m Gemini South Telescope
as part of our program for rapid ToO observations of newly discovered
transients with DLT40 (PID GS-2019B-Q-125; PI D. Sand). In addition,
we obtained two spectra with the Las Cumbres Observatory FLOYDS
spectrograph on the 2m Faulkes Telescope North (FTN) on Haleakala in
Hawaii and one spectrum with the Robert Stobie Spectrograph (RSS) on
the 10m Southern African Large Telescope (SALT). Our last optical
spectrum was obtained with the Alhambra Faint Object Spectrograph and
Camera (ALFOSC) on the 2.56m Nordic Optical Telescope (NOT) at the
Spanish Observatorio del Roque de los Muchachos on La Palma using the
low-resolution Gr4 300 lines mm-1 grism (OPTICON 19B-053;
PI N. Blagorodnova).
A late-time NIR spectrum was obtained with the Near-Infrared
Echellette Spectrometer (NIRES) on the 10m Keck II Telescope on
Maunakea in Hawaii on 2019 December 4.25, ∼69 days postdiscovery.
NIRES uses a 0.55" slit and provides wavelength coverage from
9500 to 24600Å across five spectral orders at a mean resolution of
R=2700.
Objects:
--------------------------------------------------
RA (2000) DE Designation(s)
--------------------------------------------------
00 54 57.67 -37 38 40.0 AT 2019qyl = AT 2019qyl
--------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 56 453 Photometry from follow-up observations
table2.dat 67 6 Log of spectroscopic observations
table5.dat 31 12 Pre-eruption NIR photometry from Baade/FourStar
table6.dat 73 24 Pre-eruption IR photometry from Spitzer/IRAC
fig3.dat 46 22875 Optical and late-time NIR spectroscopic sequence
of AT2019qyl
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See also:
II/358 : SkyMapper Southern Sky Survey. DR1.1 (Wolf+, 2018)
J/A+A/442/281 : Late-type giants BVRIJHKL and Teff calib (Kucinskas+, 2005)
J/ApJ/636/1002 : Z And UBV photometry & equivalent widths (Sokoloski+, 2006)
J/A+A/506/1277 : Modelling of Magellanic Cloud C/O stars (Groenewegen+, 2009)
J/AJ/137/4810 : LMC-SAGE AGB star candidates (Srinivasan+, 2009)
J/MNRAS/394/795 : AGB stars Fornax dwarf spheroidal galaxy (Whitelock+, 2009)
J/ApJS/187/275 : Photometric histories of recurrent novae (Schaefer, 2010)
J/AJ/140/34 : Classification of nova light curves (Strope+, 2010)
J/A+A/533/A52 : X-ray monitoring of M31 novae (Henze+, 2011)
J/ApJS/197/31 : Swift X-ray obs of classical novae. II. (Schwarz+, 2011)
J/A+A/532/A54 : GRAMS carbon-star model grid (Srinivasan+, 2011)
J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
J/ApJ/800/51 : DUSTiNGS II. Metal-poor dusty AGB stars (Boyer+, 2015)
J/AJ/151/88 : LMC NIR Synoptic Survey. II (Bhardwaj+, 2016)
J/ApJ/833/149 : Opt/NIR obs. of M31N 2008-12a 2015 eruption (Darnley+, 2016)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJ/839/88 : 14 IR transients with Spitzer (SPRITEs) (Kasliwal+, 2017)
J/ApJS/228/5 : Spitzer photo ∼1million stars in M31 & 15 gal. (Khan, 2017)
J/ApJ/834/196 : Galactic novae with m≤10 from 1900 to 2015 (Shafter, 2017)
J/ApJ/852/108 : Multiwave obs. of gamma-ray NOVA Sco 2012 (Finzell+, 2018)
J/ApJ/853/62 : Optical & NIR spectra & LCs of SN2016ija (Tartaglia+, 2018)
J/ApJ/886/40 : Luminous SPIRITS IR transient follow-up obs (Jencson+, 2019)
J/ApJ/877/110 : SPIRITS cat of IR long period variables (Karambelkar+, 2019)
J/ApJ/895/31 : Photo observations of Type II SN 2018ivc (Bostroem+, 2020)
J/ApJ/912/19 : Follow-up phot. & sp. of 12 PGIR novae (De+, 2021)
J/ApJ/910/134 : Swift-XRT light curves of 13 Galactic novae (Gordon+, 2021)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [58752.2/58879.1] Modified Julian date
(JD-2400000.5)
10- 15 F6.2 d Phase [0.09/127] Time since MJD 58752.12
17- 37 A21 --- Tel Telescope and instrument used (1)
39- 43 A5 --- Band Photometric band
45 A1 --- l_mag 5-sigma limit flag on mag for a non-detection
46- 50 F5.2 mag mag [16.07/22.52] Apparent magnitude in Band (2)
53- 56 F4.2 mag e_mag [0.01/0.6]? 1-sigma uncertainty on mag
--------------------------------------------------------------------------------
Note (1): Telescope and instrument as follows:
LasCumbres1m/Sinistro = The 1m telescopes at CTIO (Chile) with the Sinistro
cameras in UBVgri bands (245 occurrences)
Swope/4Kx4K = The Swope 1m telescope at Las Campanas Observatory
(LCO) with the Direct 4kx4k imager in uBVgri bands
(142 occurrences)
DLT40 = the DLT40 PROMPT5 0.4-m telescope at CTIO with no
filter ("Open") (22 occurrences)
Swift/UVOT = the Ultraviolet/Optical telescope on board Swift
(21 occurrences)
Spitzer/IRAC = the Infrared Array Camera on board the Spitzer Space
Telescope in the 3.6 and 4.5um imaging channels
(12 occurrences)
Lulin1m/PIXIS = the Lulin One-meter telescope in Taiwan in BVgri bands
(10 occurrences)
HST_WFC3/UVIS = the Hubble Space Telescope (HST) Wide Field
Camera 3 (WFC3) UVIS channel in F555W (1 occurrence)
Note (2): Ground-based magnitudes are given in their native system, Vega
magnitudes for UBV and AB magnitudes for ugri and u'g'r'i'zs. DLT40
instrumental magnitudes are calibrated to r-band in AB magnitudes. For
space-based facilities (HST, Spitzer, and Swift), measurements are in
the Vega system.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 yr Obs.Y [2019] Year of observation (UT)
6- 8 A3 "month" Obs.M Month of observation (UT)
10- 14 F5.2 d Obs.D Decimal day of observation (UT)
16- 23 F8.2 d MJD [58752.25/58821.3] Modified Julian Date
25- 29 F5.2 d Phase [0.17/69.13] Phase
31- 43 A13 --- Tel Telescope/instrument as in Figure 3 (G1)
45- 54 A10 0.1nm Range Wavelength range in Angstroms
56- 63 A8 --- Res Resolution (λ/δλ)
65- 67 I3 km/s HaRes [210/900]? Hα resolution
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [55813.38/57015.1] Modified Julian date
(JD-2400000.5)
10- 17 F8.2 d Phase [-2939/-1737] Time since MJD 58752.12
19- 20 A2 --- Band [ HJKs] Photometric band (2MASS system)
22- 26 F5.2 mag mag [18.6/20.2] Apparent Vega magnitude in Band
28- 31 F4.2 mag e_mag [0.06/0.1] 1-sigma uncertainty on mag
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [52964.06/58593.6] Modified Julian date
(JD-2400000.5)
10- 17 F8.2 d Phase [-5789/-158] Time since MJD 58752.12
19- 22 F4.1 mJy d3.6Fnu [-1.5/8.3] Flux in IRAC 3.6um difference images
24- 26 F3.1 mJy e_d3.6Fnu [1.1/5] Uncertainty in d3.6Fnu
28- 31 F4.1 mJy 3.6Fnu [7.3/17.1] Total Flux in IRAC 3.6um (1)
33- 35 F3.1 mJy e_3.6Fnu [1.3/5] Uncertainty in 3.6Fnu
37- 41 F5.2 mag 3.6mag [18/19] IRAC 3.6um magnitude
43- 46 F4.2 mag e_3.6mag [0.09/0.4] Uncertainty in 3.6mag
48- 51 F4.1 mJy d4.5Fnu [-4.8/5.4]? Flux in IRAC 4.5um difference images
53- 55 F3.1 mJy e_d4.5Fnu [0.9/5.7]? Uncertainty in d4.5Fnu
57- 60 F4.1 mJy 4.5Fnu [3.5/13.7]? Total Flux in IRAC 4.5um (1)
62- 64 F3.1 mJy e_4.5Fnu [1/5.7]? Uncertainty in 4.5Fnu
66- 69 F4.1 mag 4.5mag [17.8/19.1]? IRAC 4.5um magnitude
71- 73 F3.1 mag e_4.5mag [0.1/1.1]? Uncertainty in 4.5mag
--------------------------------------------------------------------------------
Note (1): Total flux, including that from PSF-fitting photometry on our
reference images.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: fig3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.2 d MJD [58752.29/58821.25] Modified Julian Date
(JD-2400000.5)
10- 22 A13 --- Tel Telescope and instrument (G1)
24- 32 F9.3 0.1nm lambda [3499.7/24669.2] Observed Wavelength (1)
34- 46 E13.6 cW/m2/nm Flambda [-2.5e-14/4.2e-13]? Observed flux density
in erg/s/cm2/Å (1)
--------------------------------------------------------------------------------
Note (1): Wavelengths and flux densities given in the observer frame without
extinction corrections.
--------------------------------------------------------------------------------
Global notes:
Note (G1): Telescope and instrument as follows:
FTN/FLOYDS = the 2m Faulkes Telescope North (FTN) on Haleakala in Hawaii
Keck-2/NIRES = the 10m Keck II Telescope on Maunakea in Hawaii with the
Near-Infrared Echellette Spectrometer
SALT/RSS = the 10m Southern African Large Telescope with the
Robert Stobie Spectrograph
NOT/ALFOSC = the 2.56m Nordic Optical Telescope at the Spanish
Observatorio del Roque de los Muchachos on La Palma with
the Alhambra Faint Object Spectrograph and Camera
Gemini-S/GMOS = the 8.1m Gemini South Telescope with the Gemini
Multi-Object Spectrographs
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 27-Feb-2024