J/ApJ/953/67 X-ray burst associated to FRB200428 with Insight-HXMT (Ge+, 2023)
Reanalysis of the X-ray-burst-associated FRB 200428 with Insight-HXMT
observations.
Ge M.Y., Liu C.Z., Zhang S.N., Lu F.J., Zhang Z., Chang Z., Tuo Y.L.,
Li X.B., Li C.K., Xiong S.L., Cai C., Li X.F., Zhang R., Dai Z.G.,
Qu J.L., Song L.M., Zhang S., Wang L.J.
<Astrophys. J., 953, 67 (2023)>
=2023ApJ...953...67G 2023ApJ...953...67G
ADC_Keywords: Transient; X-ray sources; Radio sources
Keywords: Magnetars ; X-ray bursts ; Radio transient sources
Abstract:
A double-peak X-ray burst from the Galactic magnetar SGR J1935+2154
was discovered to be associated with the two radio pulses of FRB200428
separated by 28.97±0.02ms. Precise measurements of the timing and
spectral properties of the X-ray bursts are helpful for understanding
the physical origin of fast radio bursts. In this paper, we have
reconstructed some information about the hard X-ray events, which were
lost because the High Energy X-ray Telescope (HE) on board the
Insight-HXMT mission was saturated by this extremely bright burst, and
used the information to improve the temporal and spectral analyses of
the X-ray burst. The arrival times of the two X-ray peaks by fitting
the new Insight-HXMT/HE lightcurve with multi-Gaussian profiles are
2.77±0.45ms and 34.30±0.56ms after the first peak of FRB 200428,
respectively, while these two parameters are 2.57±0.52ms and
32.5±1.4ms if the fitting profile is a fast-rise and exponential
decay function. The spectrum of the two X-ray peaks could be described
by a cutoff power law with cutoff energy ∼60keV and photon index
∼1.4; the latter is softer than the result obtained in
Li+ 2021NatAs...5..378L 2021NatAs...5..378L when the two X-ray peaks appeared.
Description:
Insight-HXMT is China's first X-ray astronomical satellite, which
carries three main payloads: the High Energy X-ray telescope (HE,
20-250keV, 5100cm2), the Medium Energy X-ray telescope (ME, 5-30keV,
952cm2), and the Low Energy X-ray telescope (LE, 1-15keV, 384cm2).
Insight-HXMT was in pointing observation mode and acquired
high-quality data when FRB 200428 occurred (obsID P0314003001).
As shown in Figure 1, the lightcurves obtained from the three groups
of detectors are utilized to analyze the timing parameters, and the
systematic error is set to 0.06 for the lightcurves according to their
different responses and backgrounds of these HE detectors.
The lightcurves for different energy bands could be generated from a
procedure similar to that described in Li+ (2021NatAs...5..378L 2021NatAs...5..378L).
After saturation and deadtime corrections, three lightcurves of HE,
one in the whole energy band (15-250keV) and two narrower energy bands
(15-60keV and 60-250keV), are recovered as shown in Figures 2, 3, and
4, which display more detailed structures than the ones without
correction shown in Li+ (2021).
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
19 34 59.99 +21 56 59.9 FRB 200428 = FRB 20200428A
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 42 312 The recovered lightcurve of HE in 15-250keV
fig2.dat 43 624 The recovered lightcurves and fitting curvers
of HE in energy band 15-250keV
fig3.dat 43 624 The recovered lightcurves and fitting curvers
of HE in energy band 15-60keV
fig4.dat 43 624 The recovered lightcurves and fitting curves
of HE in energy band 60-250keV
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See also:
J/other/PASA/33.45 : FRBCAT: The Fast Radio Burst (FRB) Cat. (Petroff+, 2016)
J/ApJ/901/L7 : NIR obs. of SGR 1935+215 with PGIR (De+, 2020)
J/ApJ/902/L43 : Fermi/GBM 2019 and 2020 bursts of SGR J1935+2154 (Lin+, 2020)
J/ApJ/904/L21 : NICER SGR 1935+2154 burst & persistent emission (Younes+, 2020)
J/ApJS/257/59 : First CHIME/FRB Fast Radio Burst Cat. (CHIME/FRB Col.+, 2021)
J/MNRAS/511/1961 : New CHIME/FRB I catalog updates released (Hashimoto+, 2022)
J/A+A/675/A99 : FRBs search with Fermi-LAT (Principe+, 2023)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Type Data type (1)
11- 22 E12.5 ms Time [-419.18/559.68] Time from first peak (G2)
24- 32 E9.3 10+4ct/s CRate [0.53/8] Count Rate, 15-250keV
34- 42 E9.3 10+4ct/s e_CRate [0.05/0.8] Uncertainty in CRate
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Note (1): Data type as follows:
Normal = The recorded dataset.
Recovered = The recovered dataset.
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Byte-by-byte Description of file: fig2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Type Data type (G1)
11- 22 E12.5 ms Time [-419.18/559.68] Time from first peak (G2)
24- 33 E10.3 10+4ct/s CRate [-1.42/3.8] Count Rate, 15-250keV
35- 43 E9.3 10+4ct/s e_CRate [0.05/0.8] Uncertainty in CRate
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Byte-by-byte Description of file: fig3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Type Data type (G1)
11- 22 E12.5 ms Time [-419.18/559.68] Time from first peak (G2)
24- 33 E10.3 10+4ct/s CRate [-1.1/2.54] Count Rate, 15-60keV
35- 43 E9.3 10+4ct/s e_CRate [0.024/0.7] Uncertainty in CRate
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Byte-by-byte Description of file: fig4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Type Data type (G1)
11- 22 E12.5 ms Time [-419.18/559.68] Time from first peak (G2)
24- 33 E10.3 10+4ct/s CRate [-0.73/2.9] Count Rate, 60-250keV
35- 43 E9.3 10+4ct/s e_CRate [0.02/0.7] Uncertainty in CRate
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Global notes:
Note (G1): Data type as follows:
L7 = detrended with function L7 (see Equation 1)
FRED = detrended with the fast-rising exponential decay (FRED;
Norris+ 1996ApJ...459..393N 1996ApJ...459..393N) function to fit P1 and P2
See Section 3.1.
Note (G2): First peak time was 2020-04-28T14:34:24.4265 (UTC).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 24-Sep-2025