batgrbproduct analysis for trigger=1310284
batgrbproduct Analysis for Trigger=1310284
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done of the amount of data for this trigger downloaded to date.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
- 4) This page will be updated for up to 15 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.48
Process Start Time (local time): Mon May 5 20:44:20 EDT 2025
Host Name: batproc1
Current Working Dir: /local/data/bat1/prebascript/trigger1310284/GCN5_download_cron
======================================================================
Trigger: 01310284 Segment: 000
BAT Trigger Time: 768093993.024 [s; MET]
Trigger Stop: 768093994.048 [s; MET]
UTC: 2025-05-04T23:25:57.477900 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 269.612365657656 Dec: -40.3494533312436 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.17
Image Trigger?: NO
Rate S/N Ratio: 37.0270171631472 [ if not an image trigger ]
Image S/N Ratio: 10.17
Flight Position: [ source = BAT ]
RA: 269.612365657656 Dec: -40.3494533312436 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 269.605389378116 Dec: -40.3449452143055 [deg; J2000]
{ 17h 58m 25.3s , -40d 20' 41.8" }
+/- 1.06110062022466 [arcmin] (estimated 90% radius based on SNR)
+/- 0.407595013451944 [arcmin] (formal 1-sigma fit error)
SNR: 27.9462334284385
Angular difference between Flight and Ground position is 0.418249 arcmin
Partial Coding Fraction: 0.984375 [ including projection effects ]
Duration
T90: 52.3880000114441 +/- 2.31264004440944
Measured from: -1.78799998760223
to: 50.6000000238419 [s; relative to TRIGTIME]
T50: 31.3199999332428 +/- 2.0377595211364
Measured from: 3.54800009727478
to: 34.8680000305176 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 7.7039999961853
to: 8.7039999961853 [s; relative to TRIGTIME]
Total Fluence
Measured from: -2.95600008964539
to: 55.095999956131 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.797905 1.327762 1.073338 0.340288
0.056007 0.053148 0.045004 0.037290 [error]
Peak 0.021143 0.064963 0.103610 0.028908
0.007740 0.008129 0.007702 0.006231 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
=== 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 Power-law 2.40e-07 5.07e-07 8.39e-07 3.16e-06 2.31e-06 4.74e-06 erg/cm2
Error 2.16e-08 2.65e-08 4.37e-08 3.82e-07 1.10e-07 4.03e-07 erg/cm2
Peak flux Power-law 2.64e-01 4.35e-01 5.44e-01 1.35e+00 1.62e+00 2.59e+00 ph/cm2/s
Error 6.58e-02 6.67e-02 5.67e-02 3.07e-01 1.77e-01 3.18e-01 ph/cm2/s
Fluence Cutoff-PL 2.32e-07 5.12e-07 8.50e-07 2.57e-06 2.29e-06 4.16e-06 erg/cm2
Error 2.60e-08 2.86e-08 4.95e-08 9.21e-07 1.18e-07 8.16e-07 erg/cm2
Peak flux Cutoff-PL 1.77e-01 4.32e-01 6.18e-01 5.92e-01 1.55e+00 1.82e+00 ph/cm2/s
Error 8.40e-02 7.80e-02 8.00e-02 3.64e-01 1.85e-01 4.14e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band -------- -------- -------- -------- -------- -------- ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.272 0.082 - - 4.00e-03 1.76e-04 40.800 57
CPL 1.128 0.262 332.2 0.0 4.67e-03 1.37e-03 40.210 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.680 0.187 - - 1.40e-02 1.62e-03 72.630 57
CPL -0.475 1.025 136.8 125.6 3.94e-02 4.11e-02 67.340 56
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^-{Ph_index} (minus sign is not included in the 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 PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedom
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
T90 in the 50-300 keV band: 47.872000 sec.
T50 in the 50-300 keV band: 25.152000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 58.052 -2.956 55.096
T90 52.388 -1.788 50.600
T50 31.320 3.548 34.868
Peak 1.000 7.704 8.704
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
269.6054 -40.3449 0.0069 10.4 -97.6 1.7872 27.9 TRIG_01310284
------------------------------------------
Foreground time interval of the image:
-2.956 12.877 (delta_t = 15.833 [sec])
Background time interval of the image:
-41.723 -2.956 (delta_t = 38.767 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) The mask-weighted light curves are using the flight position.
- 3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 4) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 5) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 6) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) For long bursts, a spectral fit of 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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -2.956 sec. to 55.096 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.27177 ( -0.0819313 0.0813494 )
Norm@50keV : 4.00426E-03 ( -0.0001757 0.000175651 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.80 using 59 PHA bins.
# Reduced chi-squared = 0.7159 for 57 degrees of freedom
# Null hypothesis probability = 9.480504e-01
Photon flux (15-150 keV) in 58.05 sec: 0.475323 ( -0.0222292 0.0222886 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.31323e-06 ( -1.09561e-07 1.09895e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.956 sec. to 55.096 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12773 ( -0.336271 0.186994 )
Epeak [keV] : 332.224 ( -332.229 -332.229 )
Norm@50keV : 4.66731E-03 ( -0.000798975 0.00194064 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.21 using 59 PHA bins.
# Reduced chi-squared = 0.7180 for 56 degrees of freedom
# Null hypothesis probability = 9.448408e-01
Photon flux (15-150 keV) in 58.05 sec: 0.471200 ( -0.023896 0.023385 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.29154e-06 ( -1.21458e-07 1.14219e-07 ) ergs/cm2
Band function
Time interval is from -2.956 sec. to 55.096 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.756709 ( 0.750673 0.750673 )
beta : -1.36800 ( 1.37097 0.143829 )
Epeak [keV] : 102.998 ( -103.859 495.586 )
Norm@50keV : 7.61416E-03 ( -0.00344945 0.0486879 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.87 using 59 PHA bins.
# Reduced chi-squared = 0.7068 for 55 degrees of freedom
# Null hypothesis probability = 9.510525e-01
Photon flux (15-150 keV) in 58.05 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 18.3726 ( )
R^2/D10^2 : 2.76895E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 134.86 using 59 PHA bins.
# Reduced chi-squared = 2.3660 for 57 degrees of freedom
# Null hypothesis probability = 2.956567e-08
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.079e-07 1.007e-08
25- 50 5.067e-07 3.306e-08
50-150 1.248e-06 9.665e-08
15-150 1.862e-06 1.001e-07
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-8.08328 -200)
Norm : 2.00022 (-0.0887286 0.0887286)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.892e-07 1.384e-08
25- 50 5.564e-07 3.106e-08
50-150 1.220e-06 6.676e-08
15-150 2.066e-06 1.129e-07
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.73817 (-1.74953 1.82906)
R1^2/D10^2 : 0.154502 (-0.0583476 0.119134)
kT2 [keV] : 40.3751 (-10.0941 27.6702)
R2^2/D10^2 : 1.69083E-03 (-0.00125517 0.00259028)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.921e-07 3.402e-08
25- 50 5.509e-07 6.925e-08
50-150 1.555e-06 6.320e-07
15-150 2.298e-06 6.011e-07
Peak spectrum fit
Power-law model
Time interval is from 7.704 sec. to 8.704 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.679736 ( -0.192362 0.181981 )
Norm@50keV : 1.40113E-02 ( -0.0016302 0.00160353 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.63 using 59 PHA bins.
# Reduced chi-squared = 1.274 for 57 degrees of freedom
# Null hypothesis probability = 7.931910e-02
Photon flux (15-150 keV) in 1 sec: 1.62230 ( -0.176309 0.177193 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.72608e-07 ( -1.86886e-08 1.87533e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.704 sec. to 8.704 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.474790 ( -1.16637 0.88447 )
Epeak [keV] : 136.829 ( -37.0539 214.123 )
Norm@50keV : 3.93655E-02 ( -0.0211207 0.0610951 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.34 using 59 PHA bins.
# Reduced chi-squared = 1.202 for 56 degrees of freedom
# Null hypothesis probability = 1.426505e-01
Photon flux (15-150 keV) in 1 sec: 1.54891 ( -0.18519 0.1858 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66491e-07 ( -2.0084e-08 1.9884e-08 ) ergs/cm2
Band function
Time interval is from 7.704 sec. to 8.704 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.871957 ( 0.871911 0.871911 )
beta : -0.679717 ( -0.181964 0.192403 )
Epeak [keV] : 13.9501 ( -13.9487 -13.9487 )
Norm@50keV : 2.08439E-02 ( -0.00841559 272290 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.63 using 59 PHA bins.
# Reduced chi-squared = 1.321 for 55 degrees of freedom
# Null hypothesis probability = 5.576418e-02
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
XSPEC: quit
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 27.5419 (-3.5152 4.47304)
R^2/D10^2 : 3.24652E-02 (-0.0114721 0.0162934)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.055e-09 8.980e-10
25- 50 2.410e-08 4.320e-09
50-150 1.329e-07 2.140e-08
15-150 1.610e-07 2.405e-08
Thermal bremsstrahlung (OTTB)
XSPEC12>exit
XSPEC: quit
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 6.33339 ( )
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.577e-08 8.870e-09
25- 50 3.034e-08 1.674e-08
50-150 6.654e-08 3.679e-08
15-150 1.126e-07 6.270e-08
Double BB
XSPEC12>exit
XSPEC: quit
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.06705 (-6.89104 -6.89104)
R1^2/D10^2 : 0.382836 (-0.396321 -0.396321)
kT2 [keV] : 30.2850 (-5.01714 -30.2958)
R2^2/D10^2 : 2.35421E-02 (-0.023493 0.00956031)
------------------------------------------------------------
Reduced chi-squared =
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Plot creation:
Mon May 5 20:47:56 EDT 2025