batgrbproduct analysis for trigger=1423875

batgrbproduct Analysis for Trigger=1423875

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 (local time): Sat Feb 28 18:01:57 EST 2026
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1423875
======================================================================

  Trigger: 01423875      Segment: 000

  BAT Trigger Time: 787395774.4   [s; MET]
      Trigger Stop: 787395774.656   [s; MET]
               UTC: 2025-12-14T09:02:17.541060    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 330.216936794547   Dec: -9.16703482485966  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.62
     Image Trigger?:     NO
     Rate S/N Ratio:     22.0227155455452  [ if not an image trigger ]
     Image S/N Ratio:    8.62

  Flight Position:   [ source = BAT ]
    RA: 330.216936794547   Dec: -9.16703482485966  [deg; J2000]

  Ground Position:   [ source = BAT pre-slew burst ]
    RA: 330.222106635729   Dec: -9.1507422360164  [deg; J2000]  
        { 22h 00m 53.3s , -09d 09' 02.7" }
         +/- 1.14342423553149 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.391197759006801 [arcmin] (formal 1-sigma fit error)
    SNR: 25.1168378159412
 
  Angular difference between Flight and Ground position is 1.024400 arcmin
 
  Partial Coding Fraction: 0.9921875    [ including projection effects ]

  Duration
     T90: 9.60799992084503 +/- 0.691167139041994
        Measured from: 0.00400006771087646
                   to: 9.61199998855591     [s; relative to TRIGTIME]
     T50: 4.76799988746643 +/- 0.641760119077162
        Measured from: 0.720000028610229
                   to: 5.48799991607666     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.131999969482422     
                   to: 0.868000030517578     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.192000031471252     
                   to: 10.4079999923706     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.327127   0.380828   0.215374   0.037823
           0.020695   0.021701   0.018062   0.013807 [error]
 Peak      0.067959   0.103907   0.082176   0.016215
           0.006855   0.007944   0.006774   0.004619 [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 9.42e-08 1.43e-07 1.63e-07 3.55e-07 5.07e-07 7.56e-07   erg/cm2
              Error 9.88e-09 9.65e-09 1.72e-08 7.65e-08 3.98e-08 9.27e-08   erg/cm2
Peak flux Power-law 6.13e-01 6.67e-01 5.16e-01 6.55e-01 2.04e+00 2.45e+00   ph/cm2/s
              Error 8.64e-02 5.97e-02 5.24e-02 1.33e-01 1.71e-01 2.11e-01   ph/cm2/s
 
Fluence   Cutoff-PL 9.07e-08 1.48e-07 1.63e-07 2.08e-07 4.92e-07 6.12e-07   erg/cm2
              Error 1.12e-08 1.24e-08 1.81e-08 1.39e-07 4.51e-08 1.51e-07   erg/cm2
Peak flux Cutoff-PL 5.43e-01 7.13e-01 5.51e-01 3.29e-01 2.00e+00 2.14e+00   ph/cm2/s
              Error 1.03e-01 7.32e-02 6.20e-02 1.96e-01 1.75e-01 2.57e-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    1.812    0.125    -      -           5.19e-03 3.99e-04   42.010 57
CPL   1.495    0.456      72.3  -24.6      7.73e-03 4.80e-03   40.620 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    1.369    0.135    -      -           1.69e-02 1.42e-03   58.500 57
CPL   0.694    0.602      98.7  115.5      3.68e-02 2.82e-02   54.200 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: 5.312000 sec.
T50 in the 50-300 keV band: 1.536000 sec.

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100   10.600   -0.192   10.408
T90     9.608    0.004    9.612
T50     4.768    0.720    5.488
Peak    1.000   -0.132    0.868

Click here for the BAT GCN circular template

Estimated redshift from machine learning (Ukwatta et al. 2016) - may take a few minute to calcaulte

Image

Pre-slew 15.0-350.0 keV image (Event data)

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  330.2221    -9.1507   0.0077     7.0694    80.5472         0.9675908     25.117 TRIG_01423875                 
 
Foreground time interval of the image:
 -0.192   9.901 (delta_t =  10.093 [sec])
Background time interval of the image:
-163.699  -0.192 (delta_t = 163.507 [sec])

Lightcurves

Notes:

1) The mask-weighted light curves are using the flight position.
2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
3) 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.
4) 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.
5) 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)

Quad-rate summed light curves (from T0-300s to T0+1000s)

Spectral Evolution

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   -0.192 sec. to   10.408 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.81176     ( -0.123246   0.126221 )
Norm@50keV  : 5.19353E-03    ( -0.000401082   0.000396189 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   42.01     using 59 bins.
 Reduced chi-squared = 0.737018
# Null hypothesis probability of 9.31e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 10.6 sec: 0.718987 ( -0.049041  0.049076 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.06694e-07 ( -3.95766e-08  4.00148e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.192 sec. to   10.408 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.49475     ( -0.510107   0.401639 )
Epeak [keV] : 72.3191      ( -23.1729 -72.3191 )
Norm@50keV  : 7.73129E-03    ( -0.002813   0.00678677 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   40.62     using 59 bins.
 Reduced chi-squared = 0.725357
# Null hypothesis probability of 9.39e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 10.6 sec: 0.708616 ( -0.051245  0.051218 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.91581e-07 ( -4.4974e-08  4.5297e-08 ) ergs/cm2

Band function

Time interval is from   -0.192 sec. to   10.408 sec.
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  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]    : 11.4244  (-0.994869  1.10816)
R^2/D10^2   : 0.202165  (-0.0589575   0.0822193)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   93.23     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 1.75e-03 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  5.882e-08   8.363e-09
25- 50  1.745e-07   1.548e-08
50-150  1.323e-07   2.247e-08
15-150  3.656e-07   2.830e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 99.2073       (-22.5831      35.034)
Norm        : 3.16846       (-0.298755     0.343925)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   41.05     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 9.45e-01 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.778e-08   9.720e-09
25- 50  1.515e-07   1.161e-08
50-150  2.445e-07   8.231e-08
15-150  4.838e-07   8.771e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 6.27556        (-1.14697      1.25253)
R1^2/D10^2  : 1.31436        (-0.61256      1.42712)
kT2 [keV]   : 22.6970        (-4.44009      7.38586)
R2^2/D10^2  : 1.17977E-02    (-0.0076294   0.0105308)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   39.55     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 9.42e-01 with 55 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  8.930e-08   2.531e-08
25- 50  1.484e-07   3.248e-08
50-150  2.529e-07   1.004e-07
15-150  4.906e-07   1.407e-07

Peak spectrum fit

Power-law model

Time interval is from   -0.132 sec. to    0.868 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.36913     ( -0.134774   0.135414 )
Norm@50keV  : 1.68764E-02    ( -0.00141685   0.00141378 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   58.50     using 59 bins.
 Reduced chi-squared = 1.02632
# Null hypothesis probability of 4.20e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.04132 ( -0.17121  0.17132 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.64153e-07 ( -1.52478e-08  1.53617e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.132 sec. to    0.868 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.694311     ( -0.643511   0.561244 )
Epeak [keV] : 98.6818      ( -26.4301 204.48 )
Norm@50keV  : 3.68296E-02    ( -0.0172683   0.0390359 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   54.20     using 59 bins.
 Reduced chi-squared = 0.967857
# Null hypothesis probability of 5.43e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.00129 ( -0.17522  0.1749 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.57747e-07 ( -1.63761e-08  1.64096e-08 ) ergs/cm2

Band function

Time interval is from   -0.132 sec. to    0.868 sec.
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  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]    : 16.1290  (-1.54601  1.74409)
R^2/D10^2   : 0.192155  (-0.0574976   0.0798223)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   75.90     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 4.78e-02 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.032e-08   1.767e-09
25- 50  4.371e-08   4.950e-09
50-150  7.972e-08   1.294e-08
15-150  1.337e-07   1.385e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 200.000       (-31.2758      -200)
Norm        : 8.44409       (-0.699574     0.699574)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   60.56     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 3.49e-01 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.102e-08   2.070e-09
25- 50  4.044e-08   8.330e-09
50-150  8.870e-08   3.176e-08
15-150  1.502e-07   4.502e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 7.24571        (-2.66898      3.62024)
R1^2/D10^2  : 1.47813        (-0.97661      5.57947)
kT2 [keV]   : 24.0940        (-5.12468      16.1547)
R2^2/D10^2  : 3.85138E-02    (-0.0327048   0.0594855)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   54.80     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 4.82e-01 with 55 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.686e-08   7.730e-09
25- 50  4.091e-08   1.907e-08
50-150  9.880e-08   4.995e-08
15-150  1.566e-07   5.892e-08

Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)

Power-law model

 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.78885     ( -0.122164   0.124999 )
Norm@50keV  : 5.36504E-03    ( -0.000410028   0.000405281 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   41.19     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 9.43e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 10.09 sec: 0.736119 ( -0.0502523  0.0502899 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.98563e-07 ( -3.88779e-08  3.92574e-08 ) ergs/cm2

Cutoff power-law model

Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.41743     ( -0.517278   0.425463 )
Epeak [keV] : 71.7935      ( -20.5542 -71.7935 )
Norm@50keV  : 8.52495E-03    ( -0.00338245   0.00755586 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   39.32     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 9.56e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 10.09 sec: 0.723738 ( -0.052505  0.05247 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.82006e-07 ( -4.39389e-08  4.42658e-08 ) ergs/cm2

Band function

 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       :    (     )
beta        :     (     )
Epeak [keV] :       (   )
Norm@50keV   :     (     )
------------------------------------------------------------
 
Photon flux (15-150 keV)    in  sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

S(25-50 keV) vs. S(50-100 keV) plot

S(25-50 keV)  = 1.43e-07
S(50-100 keV) = 1.63e-07

T90 vs. Hardness ratio plot

T90                                   = 9.60799992084503 sec.
Hardness ratio (energy fluence ratio) = 1.13986

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.16416
Count Ratio (50-100 keV) / (15-25 keV) = 0.65838

Mask shadow pattern

IMX = 2.036770537529751E-02, IMY = -1.223310443442393E-01

TIME vs. PHA plot around the trigger time

TIME vs. DetID plot around the trigger time

100 us light curve (15-350 keV)

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:
-163.699400 -0.192000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
285.0403 -24.8008    6.5  38.7  -89.8  -1.4210  -1.8    7.2	HT1900.1-2455                 
288.8744  11.1511    0.0  42.6  -33.3  -0.7846  -1.9   13.1	GRS 1915+105                  
299.5750  35.2122    1.4  53.6   -1.4   5.0155   7.9    1.0	Cyg X-1                       
326.2997  38.3252    3.8  51.4   25.7   2.7642   3.1    6.0	Cyg X-2                       
339.7293  -5.4879    3.5  17.1   88.7   0.8747   3.2 ------	UNKNOWN                       
  4.2541 -43.3134    5.2  45.7  162.9   1.2852   2.2 ------	UNKNOWN                       
306.0756  40.5514    2.6  56.2    7.1   4.6060   4.5 ------	UNKNOWN                       
339.5752 -55.8610    2.3  44.4 -168.6   1.9845   5.0 ------	UNKNOWN

Pre-slew background subtracted image of 15-350 keV band

Time interval of the image:
-0.192000 9.900600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
285.1096 -24.9265    4.1  38.7  -90.1   0.3882   2.8    4.0	HT1900.1-2455                 
288.8138  10.8386    8.9  42.5  -33.7  -0.0974  -1.3    6.5	GRS 1915+105                  
299.5325  35.2610    4.7  53.7   -1.4  -0.3469  -2.4    4.6	Cyg X-1                       
326.0291  38.3402   10.3  51.4   25.5  -0.2368  -1.1    6.8	Cyg X-2                       
330.2221  -9.1507    0.5   7.1   80.5   0.9677  25.1 ------	UNKNOWN                       
310.4430 -53.2804    2.4  41.7 -144.0   0.3492   4.9 ------	UNKNOWN                       
297.7610 -41.7928    2.0  36.8 -122.6   0.4030   5.9 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
43.700590 172.104900
173.600000 1065.647800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
288.7282  10.7538    5.2  45.8  -43.5  -6.6909  -2.2   12.2	GRS 1915+105                  
299.5750  35.1925    1.0  53.0   -9.8  30.5706  11.4    0.9	Cyg X-1                       
308.0478  40.8564  134.0  54.0    1.0   0.2411   0.1    6.4	Cyg X-3                       
326.2644  38.1911   11.8  47.5   17.4   2.3134   1.0    9.0	Cyg X-2                       
 13.0775 -10.3494    3.4  42.2  117.0  25.6146   3.4 ------	UNKNOWN                       
338.2071  10.1041    3.2  20.8   44.3   4.7899   3.7 ------	UNKNOWN

Plot creation:
Sun Mar  1 23:10:48 EST 2026