J/ApJ/910/134 Swift-XRT light curves of 13 Galactic novae (Gordon+, 2021)
Surveying the X-ray behavior of novae as they emit γ-rays.
Gordon A.C., Aydi E., Page K.L., Li K.-L., Chomiuk L., Sokolovsky K.V.,
Mukai K., Seitz J.
<Astrophys. J., 910, 134 (2021)>
=2021ApJ...910..134G 2021ApJ...910..134G
ADC_Keywords: Novae; Gamma rays; X-ray sources
Keywords: Classical novae ; Novae ; X-ray astronomy ;
Cataclysmic variable stars ; White dwarf stars ;
Gamma-ray astronomy ; Gamma-ray transient sources ;
Symbiotic binary stars ; High energy astrophysics ;
Observational astronomy ; Shocks
Abstract:
The detection of GeV γ-ray emission from Galactic novae by the
Fermi-Large Area Telescope has become routine since 2010, and is
generally associated with shocks internal to the nova ejecta. These
shocks are also expected to heat plasma to ∼107K, resulting in
detectable X-ray emission. In this paper, we investigate
13 γ-ray emitting novae observed with the Neil Gehrels Swift
Observatory, searching for 1-10keV X-ray emission concurrent with
γ-ray detections. We also analyze γ-ray observations of
novae V407 Lup (2016) and V357 Mus (2018). We find that most novae do
eventually show X-ray evidence of hot shocked plasma, but not until
the γ-rays have faded below detectability. We suggest that the
delayed rise of the X-ray emission is due to large absorbing columns
and/or X-ray suppression by corrugated shock fronts. The only nova in
our sample with a concurrent X-ray/γ-ray detection is also the
only embedded nova (V407 Cyg). This exception supports a scenario
where novae with giant companions produce shocks with external
circumbinary material and are characterized by lower density
environments, in comparison with novae with dwarf companions where
shocks occur internal to the dense ejecta.
Description:
In this paper, we analyze all Galactic novae observed by Fermi-LAT
between 2010 and 2018 that have a time-integrated detection of
≥3σ significance over the period of γ-ray emission.
We downloaded the LAT data (Pass 8, Release 3, Version 2 with the
instrument response functions of P8R3SOURCEV2) from the data server
at the Fermi Science Support Center.
In Figures A1-A13, we present the Swift X-ray (0.3-10keV) light curves
of all the novae in our sample.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 63 13 Characteristics of γ-ray detections of
novae (2010-2018), in reverse chronological order
table2.dat 120 13 Nova properties
figa1.dat 62 44 V392 Per XRT data
figa2.dat 62 45 V906 Car XRT data
figa3.dat 62 52 V357 Mus XRT data
figa4.dat 62 33 V549 Vel XRT data
figa5.dat 62 2 V5856 Sgr XRT data
figa6.dat 62 3 V5855 Sgr XRT data
figa7.dat 62 126 V407 Lup XRT data
figa8.dat 62 185 V5668 Sgr XRT data
figa9.dat 62 135 V1369 Cen XRT data
figa10.dat 62 206 V339 Del XRT data
figa11.dat 62 138 V959 Mon XRT data
figa12.dat 62 10 V1324 Sco XRT data
figa13.dat 62 44 V407 Cyg XRT data
--------------------------------------------------------------------------------
See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
B/swift : Swift Master Catalog (HEASARC, 2004-)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
J/ApJS/197/31 : Swift X-ray obs. of classical novae. II. (Schwarz+, 2011)
J/ApJ/734/12 : Survey of novae in M31 (Shafter+, 2011)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/MNRAS/469/4341 : Seven recent novae BVI light curves (Munari+, 2017)
J/ApJ/852/108 : Multiwavelength obs. of NOVA Sco 2012 (Finzell+, 2018)
J/A+A/639/L10 : VRI photometry of V392 Per (Munari+, 2020)
J/ApJS/247/33 : Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)
http://www.astrosurf.com/aras/Aras_DataBase/Novae.htm : ARAS spectral database
http://fermi.gsfc.nasa.gov/ssc/ : Fermi Science Support Center home page
http://www.aavso.org/ : AAVSO home page
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Name of the nova
11- 15 I5 d MJDst [55265/58238] Time γ-ray start
17 A1 --- f_MJDst Flag on MJDst (1)
19- 23 I5 d MJDend [55287/58246] Time γ-ray end
24 A1 --- --- [-]
25- 29 I5 d MJDend2 ? Upper range of time γ-ray end
31 A1 --- f_MJDend2 Flag on MJDend2 (1)
33- 36 F4.1 10-7ph/s/cm2 FGeV [0.4/12.2] Average flux over the energy
range of >100MeV
38- 40 F3.1 10-7ph/s/cm2 e_FGeV [0.2/0.9] FGeV uncertainty
42- 45 F4.2 --- Ind [1.8/2.42] Photon index (2)
47- 50 F4.2 --- e_Ind [0.02/0.3] Ind uncertainty
52- 63 A12 --- Ref Reference (3)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = Due to Fermi-LAT downtime, data are not available for MJD 58224-58238.
When observations resumed on MJD 58238, V392 Per was immediately detected.
The γ-ray flux is calculated over MJD 58238-58246.
b = Due to Fermi-LAT downtime, the start time of γ-ray detection for
V906 Car was not captured, and the end time is only constrained to be
within a date range. The γ-ray flux is calculated over
MJD 58216-58239.
Note (2): The photon index for a single power-law fit to the Fermi-LAT data
with energy >100MeV: dN/dE∝E-Γ (Equation (1))
where N is the number of photons, E is the photon energy, and
Γ is the photon index.
Note (3): Reference as follows:
1 = Ackermann et al. (2014Sci...345..554A 2014Sci...345..554A)
2 = Cheung et al. (2016ApJ...826..142C 2016ApJ...826..142C)
3 = Cheung et al. (2016ATel.9594....1C 2016ATel.9594....1C)
4 = Nelson et al. (2019ApJ...872...86N 2019ApJ...872...86N)
5 = Li et al. (2017ATel10977....1L 2017ATel10977....1L)
6 = Li et al. (2017NatAs...1..697L 2017NatAs...1..697L)
7 = Li et al. (2020ApJ...905..114L 2020ApJ...905..114L)
8 = Li et al. (2018ATel11201....1L 2018ATel11201....1L)
9 = Aydi et al. (2020NatAs...4..776A 2020NatAs...4..776A)
10 = Li et al. (2018ATel11590....1L 2018ATel11590....1L)
11 = B. Linnemann et al. (2020 in preparation).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Name of the nova
11- 18 F8.2 d MJD0 [55265.8/58237.5] Modified Julian Date, t0 (4)
20- 21 I2 --- r_MJD0 [1/28] Reference on MJD0 (5)
23- 26 I4 yr Date.Y Year of first observation in eruption, t0
27 A1 --- --- [-]
28- 29 I2 "month" Date.M Month of first observation in eruption, t0
30 A1 --- --- [-]
31- 35 F5.2 d Date.D Day of first observation in eruption, t0;
in decimal days
37- 38 I2 --- r_Date [1/28] Reference on Date (5)
40 A1 --- l_mag [~<] Limit or uncertainty flag on mag
41- 44 F4.1 mag mag Discovery optical magnitude at t0; V-band
unless otherwise noted
46 A1 --- f_mag Flag on mag (6)
48- 49 I2 --- r_mag [1/24] Reference on mag (5)
51 A1 --- l_Vmax [~<] Limit or uncertainty flag on Vmax
52- 54 F3.1 mag Vmax ? Peak magnitude in the V band (7)
55 A1 --- f_Vmax Flag on Vmax (6)
57- 58 I2 --- r_Vmax [2/28] Reference on Vmax (5)
60 A1 --- Dust? [Y/N] Dust?
62- 63 I2 --- r_Dust? [2/28]? Reference on Dust? (5)
65- 68 F4.1 d t2 [3/90] Time for the optical light curve to
decline by two magnitudes from the maximum (7)
70 I1 d e_t2 [1/5]? t2 uncertainty
72- 73 I2 --- r_t2 [2/29] Reference on t2 (5)
75- 79 A5 --- SpCl Spectral classification (8)
81- 82 I2 --- r_SpCl [2/28] Reference on SpCl (5)
84- 87 I4 km/s FWHM [200/4700] Line Full Width at Half Maximum (8)
89- 91 I3 km/s e_FWHM [100/200] FWHM uncertainty
93 I1 --- r_FWHM [2] Reference on FWHM (5)
95 A1 --- l_Dist Limit flag on Dist
96- 98 F3.1 kpc Dist Distance
100- 102 F3.1 kpc e_Dist [0.4/1.5]? Lower uncertainty on Dist
104- 106 F3.1 kpc E_Dist [0.4/2.3]? Upper uncertainty on Dist
108- 109 I2 --- r_Dist [2/29] Reference on Dist (5)
111- 114 F4.1 10+21cm-2 NH [0.6/10.1]? Hydrogen column density (8)
116- 118 F3.1 10+21cm-2 e_NH [0.1/1.2]? NH uncertainty
120 I1 --- r_NH [2]? Reference on NH (5)
--------------------------------------------------------------------------------
Note (4): Date of first observation in eruption.
Note (5): Reference as follows:
1 = Munari & Ochner (2018ATel11926....1M 2018ATel11926....1M)
2 = This work
3 = Stanek et al. (2018ATel11454....1S 2018ATel11454....1S)
4 = ASAS-SN data Walter (2018ATel11298....1W 2018ATel11298....1W)
5 = Aydi et al. (2018ATel11221....1A 2018ATel11221....1A)
6 = Stanek et al. (2017ATel11110....1S 2017ATel11110....1S)
7 = Luckas (2017ATel10975....1L 2017ATel10975....1L)
8 = Li et al. (2017NatAs...1..697L 2017NatAs...1..697L)
9 = AAVSO Alert 561;
10 = Munari et al. (2017, J/MNRAS/469/4341)
11 = Nelson et al. (2019ApJ...872...86N 2019ApJ...872...86N)
12 = Luckas (2016ATel.9658....1L 2016ATel.9658....1L)
13 = Stanek et al. (2016ATel.9538....1S 2016ATel.9538....1S)
14 = Aydi et al. (2018MNRAS.480..572A 2018MNRAS.480..572A)
15 = Cheung et al. (2016ApJ...826..142C 2016ApJ...826..142C)
16 = Gehrz et al. (2018ApJ...858...78G 2018ApJ...858...78G)
17 = Banerjee et al. (2015ATel.7748....1B 2015ATel.7748....1B)
18 = Waagen et al. (2013CBET.3732....3W 2013CBET.3732....3W)
19 = Waagen (2014AAN...496....1W 2014AAN...496....1W)
20 = Ackermann et al. (2014Sci...345..554A 2014Sci...345..554A)
21 = Munari (2013ATel.4709....1M 2013ATel.4709....1M)
22 = Finzell et al. (2018, J/ApJ/852/108)
23 = Wagner et al. (2012ATel.4157....1W 2012ATel.4157....1W)
24 = Munari et al. (2011MNRAS.410L..52M 2011MNRAS.410L..52M)
25 = Schaefer (2018MNRAS.481.3033S 2018MNRAS.481.3033S)
26 = Linford et al. (2015ApJ...805..136L 2015ApJ...805..136L)
27 = Shugarov et al. (2014ASPC..490..217S 2014ASPC..490..217S)
28 = Aydi et al. (2020NatAs...4..776A 2020NatAs...4..776A)
29 = Chochol et al. (2021gacv.workE..29C)
30 = Finzell et al. (2015ApJ...809..160F 2015ApJ...809..160F)
Note (6): Flag on mag as follows:
c = Image was saturated.
d = Image was obtained in an unfiltered optical band.
e = Image was obtained in the I band.
f = Optical maximum was during solar conjunction, so was missed.
Note (7): The peak magnitude and t2 are determined from reports in the
literature or derived in this work using publicly available photometry
from the AAVSO, ASAS-SN, and the Stony Brook/SMARTS Atlas.
Note (8): We give the spectroscopic class (FeII or He/N;
Williams 1992AJ....104..725W 1992AJ....104..725W) and the FWHM of Balmer emission lines
after optical peak. The spectroscopic classes are based on previous
reports in the literature or determined based on spectra obtained
around optical peak (≲t2). These spectra are either publicly
available spectra from the Astronomical Ring for Access to
Spectroscopy (ARAS; Teyssier 2019CoSka..49..217T 2019CoSka..49..217T) or from our private
database.
We also use high-resolution optical spectroscopy to estimate the
Galactic column density toward each nova. Again, these spectra are
either from ARAS or from our private database, and are obtained near
the light-curve peak.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: figa[1-9].dat figa1[0-3].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 F11.5 --- MJD [55268/58952] Modified Julian Date of
the observation
13- 23 A11 --- ObsID Observation identifier
25- 32 E8.2 ct/s HardRate [0.0005/5] The 1-10keV rate
34- 41 E8.2 ct/s e_HardRate [0/0.07] Uncertainty in HardRate (1)
43- 50 E8.2 ct/s SoftRate [0.0005/71] The 0.3-1keV rate
52- 59 E8.2 ct/s e_SoftRate [0/7] Uncertainty in SoftRate (1)
61- 62 A2 --- Mode Observation mode (2)
--------------------------------------------------------------------------------
Note (1): An error of 0.00E+00 denotes the observation was an upper limit.
Note (2): Observation mode as follows:
PC = photon counting;
WT = windowed timing.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 16-Sep-2022