Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done using the HEASARC data.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.48
Process Start Time: Thu Jun 19 22:17:48 EDT 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1273071
======================================================================
Trigger: 01273071 Segment: 000
BAT Trigger Time: 755415378.752 [s; MET]
Trigger Stop: 755415379.008 [s; MET]
UTC: 2024-12-09T05:35:44.072300 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 155.375872930398 Dec: 6.31605205716822 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.18
Image Trigger?: NO
Rate S/N Ratio: 17.464249196573 [ if not an image trigger ]
Image S/N Ratio: 8.18
Analysis Position: [ source = BAT ]
RA: 155.375872930398 Dec: 6.31605205716822 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 155.365442427258 Dec: 6.34929337060288 [deg; J2000]
{ 10h 21m 27.7s , +06d 20' 57.5" }
+/- 2.1042273368478 [arcmin] (estimated 90% radius based on SNR)
+/- 1.05299949578808 [arcmin] (formal 1-sigma fit error)
SNR: 10.5089043556603
Angular difference between the analysis and refined position is 2.089221 arcmin
Partial Coding Fraction: 0.6953125 [ including projection effects ]
Duration
T90: 0.25599992275238 +/- 0.0905096828275688
Measured from: -0.0720000267028809
to: 0.1839998960495 [s; relative to TRIGTIME]
T50: 0.127999901771545 +/- 0.0640000104904175
Measured from: -0.00800001621246338
to: 0.119999885559082 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.411999940872192
to: 0.588000059127808 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0720000267028809
to: 0.184000015258789 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.012961 0.024021 0.030454 0.013795
0.004141 0.004872 0.004917 0.003373 [error]
Peak 0.005245 0.032075 0.040235 0.020964
0.007642 0.008409 0.007774 0.006205 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 0.256 -0.072 0.184
T90 0.256 -0.072 0.184
T50 0.128 -0.008 0.120
Peak 1.000 -0.412 0.588
====== Spectral Analysis Summary =====================================
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^{Ph_index}
Ph_90err : 90% error of the photon index
Epeak : Epeak in keV
Epeak_90err: 90% error of Epeak
Norm : normalization at 50 keV in both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedo
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.050 -0.278 0.289 - - - 2.00e-02 -3.69e-03 3.66e-03 50.580 57
CPL -0.357 -0.879 1.527 146.921 -63.176 -146.921 3.93e-02 -2.19e-02 1.14e-01 49.560 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -0.842 -0.384 0.439 - - - 6.43e-03 -1.73e-03 1.66e-03 48.510 57
CPL 0.168 -1.308 2.728 132.255 -57.156 -132.255 1.68e-02 -1.68e-02 1.65e-01 47.620 56
=== Fluence/Peak Flux Summary ===
Model Band1 Band2 Band3 Band4 Band5 Total
15-25 25-50 50-100 100-350 15-150 15-350 keV
Fluence PL 4.30e-09 1.04e-08 2.01e-08 9.56e-08 5.45e-08 1.30e-07 erg/cm2
90%_error_low -1.42e-09 -2.32e-09 -3.85e-09 -3.39e-08 -1.01e-08 -3.68e-08 erg/cm2
90%_error_hi 1.58e-09 2.27e-09 3.80e-09 4.35e-08 1.01e-08 4.46e-08 erg/cm2
Peak flux PL 1.42e-01 2.11e-01 2.36e-01 4.97e-01 7.39e-01 1.09e+00 ph/cm2/s
90%_error_low -6.87e-02 -7.30e-02 -5.52e-02 -2.03e-01 -1.89e-01 -2.63e-01 ph/cm2/s
90%_error_hi 8.49e-02 7.22e-02 5.51e-02 2.83e-01 1.92e-01 2.75e-01 ph/cm2/s
Fluence CPL 3.55e-09 1.09e-08 2.23e-08 4.85e-08 5.47e-08 8.52e-08 erg/cm2
90%_error_low -1.77e-09 -2.57e-09 -5.17e-09 -3.12e-08 -1.03e-08 -3.23e-08 erg/cm2
90%_error_hi 1.98e-09 2.62e-09 5.49e-09 6.10e-08 1.03e-08 6.21e-08 erg/cm2
Peak flux CPL 1.04e-01 2.17e-01 2.68e-01 2.36e-01 7.19e-01 8.25e-01 ph/cm2/s
90%_error_low -7.52e-02 -8.30e-02 -7.66e-02 -2.36e-01 -1.90e-01 -2.65e-01 ph/cm2/s
90%_error_hi 1.05e-01 4.15e-02 8.20e-02 2.65e-01 1.95e-01 4.09e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 155.3654 6.3493 0.0183 33.3040 2.2313 0.0858576 10.509 TRIG_01273071 Foreground time interval of the image: -0.072 0.184 (delta_t = 0.256 [sec]) Background time interval of the image: -51.051 -0.072 (delta_t = 50.979 [sec])
Light Curves
Note: The mask-weighted lightcurves have units of either count/det or counts/sec/det, where a det is 0.4 x 0.4 = 0.16 sq cm.
Full-time range; 1 s binning
Other quick-look light curves:
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -0.072 sec. to 0.184 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.04966 ( -0.278251 0.289438 ) Norm@50keV : 2.00266E-02 ( -0.00369314 0.00365912 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 50.58 using 59 bins. Reduced chi-squared = 0.887368 # Null hypothesis probability of 7.13e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 0.256 sec: 2.31294 ( -0.43666 0.43841 ) ph/cm2/s Energy fluence (15-150 keV) : 5.45004e-08 ( -1.01098e-08 1.01142e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.072 sec. to 0.184 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.357039 ( -0.878831 1.52659 ) Epeak [keV] : 146.921 ( -63.1751 -146.92 ) Norm@50keV : 3.92575E-02 ( -0.0219367 0.113816 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 49.56 using 59 bins. Reduced chi-squared = 0.885 # Null hypothesis probability of 7.16e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 0.256 sec: 2.28396 ( -0.44 0.44188 ) ph/cm2/s Energy fluence (15-150 keV) : 5.46675e-08 ( -1.03424e-08 1.02826e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.412 sec. to 0.588 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.842147 ( -0.383891 0.439454 ) Norm@50keV : 6.43494E-03 ( -0.00172921 0.00165948 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 48.51 using 59 bins. Reduced chi-squared = 0.851053 # Null hypothesis probability of 7.81e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 0.738763 ( -0.18918 0.192275 ) ph/cm2/s Energy fluence (15-150 keV) : 7.39061e-08 ( -1.75034e-08 1.75073e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.412 sec. to 0.588 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 0.16823 ( -1.30795 2.72819 ) Epeak [keV] : 132.255 ( -57.1582 -132.257 ) Norm@50keV : 1.68449E-02 ( -0.0168444 0.164646 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 47.62 using 59 bins. Reduced chi-squared = 0.850357 # Null hypothesis probability of 7.80e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 0.718602 ( -0.189519 0.195136 ) ph/cm2/s Energy fluence (15-150 keV) : 7.24086e-08 ( -1.86559e-08 1.80917e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 0.2559999 sec. Hardness ratio (energy fluence ratio) = 1.93236916543
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.4726378e-08 S(50-150 keV) = 3.977423e-08
The dash-dotted line and the dashed line traces the fluences calculated from the Band function with Epeak = 15 and 150 keV, respectively. Both lines assume a canonical values of alpha = -1 and beta = -2.5.
Mask shadow pattern
IMX = 6.564799123820915E-01, IMY = -2.557807202558693E-02
Spacecraft aspect plot
Bright source in the pre-burst/pre-slew/post-slew images
Pre-burst image of 15-350 keV band
Time interval of the image: -51.051400 -0.072000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 93.4828 69.7761 2.3 48.6 136.4 2.4014 5.1 ------ UNKNOWN 137.6329 46.3023 2.3 22.4 102.8 0.6419 5.1 ------ UNKNOWN 138.2111 36.4430 2.6 22.2 76.7 0.5478 4.5 ------ UNKNOWN 160.5510 -16.9668 3.9 55.4 -11.0 0.9466 3.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.072000 0.184000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 110.3697 81.4289 2.7 47.4 152.9 0.0799 4.3 ------ UNKNOWN 155.3655 6.3493 1.1 33.3 2.2 0.0858 10.5 ------ UNKNOWN 214.1874 26.4534 2.3 41.8 -105.8 0.1515 5.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 89.748600 962.307800 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5290 -40.5481 1.3 50.3 -2.3 14.8192 8.8 0.4 Vela X-1 143.3480 -46.7349 2.4 54.1 -11.7 11.0675 4.7 ------ UNKNOWN 177.3465 -8.1024 2.7 26.2 -78.9 5.5209 4.3 ------ UNKNOWN