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 21:49:44 EDT 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1280056
======================================================================
Trigger: 01280056 Segment: 000
BAT Trigger Time: 758024621.056 [s; MET]
Trigger Stop: 758024625.152 [s; MET]
UTC: 2025-01-08T10:23:06.198080 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 201.297419885604 Dec: 25.6127383632345 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.13
Image Trigger?: NO
Rate S/N Ratio: 10.8627804912002 [ if not an image trigger ]
Image S/N Ratio: 8.13
Analysis Position: [ source = BAT ]
RA: 201.297419885604 Dec: 25.6127383632345 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 201.311275230995 Dec: 25.623941949205 [deg; J2000]
{ 13h 25m 14.7s , +25d 37' 26.2" }
+/- 1.80589057530568 [arcmin] (estimated 90% radius based on SNR)
+/- 0.700792169240201 [arcmin] (formal 1-sigma fit error)
SNR: 13.0742364504919
Angular difference between the analysis and refined position is 1.006861 arcmin
Partial Coding Fraction: 0.8984375 [ including projection effects ]
Duration
T90: 218.111999988556 +/- 90.4783376800142
Measured from: -54.1759999990463
to: 163.93599998951 [s; relative to TRIGTIME]
T50: 47.4880000352859 +/- 32.3538594980207
Measured from: -3.82400000095367
to: 43.6640000343323 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.55599999427795
to: 2.55599999427795 [s; relative to TRIGTIME]
Total Fluence
Measured from: -63.1360000371933
to: 218.208000063896 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.955544 0.998971 0.749620 0.190283
0.097187 0.100436 0.085352 0.070961 [error]
Peak 0.015855 0.027034 0.026120 0.011130
0.006085 0.006491 0.005966 0.004577 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 281.344 -63.136 218.208
T90 218.112 -54.176 163.936
T50 47.488 -3.824 43.664
Peak 1.000 1.556 2.556
====== 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 -1.624 -0.193 0.189 - - - 6.43e-04 -7.12e-05 7.01e-05 62.960 57
CPL -1.629 -0.187 0.197 9999.360 -9999.350 -9999.360 6.43e-04 -2.49e-04 4.01e-04 62.970 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 -0.930 -0.447 0.516 - - - 5.19e-03 -1.35e-03 1.28e-03 58.810 57
CPL -0.942 -0.433 0.755 9999.360 -9999.360 -9999.360 5.24e-03 -1.23e-03 8.05e-03 58.830 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 2.60e-07 4.42e-07 5.74e-07 1.50e-06 1.69e-06 2.78e-06 erg/cm2
90%_error_low -4.34e-08 -4.60e-08 -8.61e-08 -4.29e-07 -2.00e-07 -5.10e-07 erg/cm2
90%_error_hi 4.49e-08 4.58e-08 8.57e-08 5.33e-07 2.02e-07 5.93e-07 erg/cm2
Peak flux PL 1.24e-01 1.76e-01 1.84e-01 3.57e-01 5.96e-01 8.40e-01 ph/cm2/s
90%_error_low -6.39e-02 -6.19e-02 -4.59e-02 -1.68e-01 -1.51e-01 -2.10e-01 ph/cm2/s
90%_error_hi 7.73e-02 5.78e-02 4.49e-02 2.62e-01 1.51e-01 2.31e-01 ph/cm2/s
Fluence CPL 2.60e-07 4.35e-07 5.74e-07 1.50e-06 1.69e-06 2.83e-06 erg/cm2
90%_error_low -4.35e-08 -5.38e-08 -8.61e-08 -1.52e-07 -2.00e-07 -9.06e-07 erg/cm2
90%_error_hi 4.49e-08 6.77e-08 8.57e-08 5.29e-07 2.02e-07 2.07e-07 erg/cm2
Peak flux CPL 1.24e-01 1.76e-01 1.84e-01 3.53e-01 5.96e-01 8.89e-01 ph/cm2/s
90%_error_low -6.40e-02 -6.20e-02 -4.59e-02 -8.26e-02 -1.51e-01 -4.02e-01 ph/cm2/s
90%_error_hi 7.73e-02 5.79e-02 4.50e-02 2.59e-01 1.51e-01 2.66e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 201.3113 25.6239 0.0147 25.3208 -151.9481 1.8900647 13.074 TRIG_01280056 Foreground time interval of the image: -63.136 34.645 (delta_t = 97.781 [sec]) Background time interval of the image: -239.056 -63.136 (delta_t = 175.920 [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 -63.136 sec. to 218.208 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.62411 ( -0.192729 0.188932 ) Norm@50keV : 6.42983E-04 ( -7.12043e-05 7.00916e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 62.96 using 59 bins. Reduced chi-squared = 1.10456 # Null hypothesis probability of 2.74e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 281.3 sec: 8.32582E-02 ( -0.0085896 0.0086034 ) ph/cm2/s Energy fluence (15-150 keV) : 1.68702e-06 ( -2.00056e-07 2.02494e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -63.136 sec. to 218.208 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.62913 ( -0.187791 0.19618 ) Epeak [keV] : 9999.36 ( -9999.35 -9999.36 ) Norm@50keV : 6.43321E-04 ( -0.000249105 0.000401045 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 62.97 using 59 bins. Reduced chi-squared = 1.12446 # Null hypothesis probability of 2.43e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 281.3 sec: 8.32551E-02 ( -0.008597 0.0085979 ) ph/cm2/s Energy fluence (15-150 keV) : 1.68659e-06 ( -2.00211e-07 2.02443e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.556 sec. to 2.556 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.930293 ( -0.447196 0.516423 ) Norm@50keV : 5.18943E-03 ( -0.00135007 0.0012785 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 58.81 using 59 bins. Reduced chi-squared = 1.03175 # Null hypothesis probability of 4.09e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 0.595897 ( -0.150571 0.151414 ) ph/cm2/s Energy fluence (15-150 keV) : 5.75732e-08 ( -1.43278e-08 1.43767e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.556 sec. to 2.556 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.941807 ( -0.434345 0.753484 ) Epeak [keV] : 9999.36 ( -9999.36 -9999.36 ) Norm@50keV : 5.23858E-03 ( -0.0012242 0.00805731 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 58.83 using 59 bins. Reduced chi-squared = 1.05054 # Null hypothesis probability of 3.72e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 0.595880 ( -0.150685 0.151283 ) ph/cm2/s Energy fluence (15-150 keV) : 5.75771e-08 ( -1.43556e-08 1.43661e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 218.112 sec. Hardness ratio (energy fluence ratio) = 1.29768683878
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 7.015864e-07 S(50-150 keV) = 9.854358e-07
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 = -4.175576600804364E-01, IMY = 2.225047426076106E-01
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: -239.056000 -63.136000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 180.8333 -37.8027 2.6 44.9 -9.8 1.6485 4.4 ------ UNKNOWN 212.8918 38.3743 2.2 41.2 -156.6 1.9574 5.2 ------ UNKNOWN 203.8480 -45.7546 2.8 55.9 -29.8 5.1248 4.1 ------ UNKNOWN 230.2548 24.3532 3.0 48.1 -129.2 3.9254 3.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -63.136000 34.644600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 154.1209 -17.8547 2.7 38.1 36.3 1.0532 4.3 ------ UNKNOWN 201.3113 25.6239 0.9 25.3 -151.9 1.8896 13.1 ------ UNKNOWN 206.2216 -4.5894 2.3 25.6 -76.3 0.8496 5.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 96.044590 963.058300 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3997 35.4475 5.4 46.2 -136.1 -5.5506 -2.1 6.9 Her X-1 255.9716 30.2195 2.7 48.1 -129.2 21.0531 4.3 ------ UNKNOWN