batgrbproduct analysis for trigger=1277428

batgrbproduct Analysis for Trigger=1277428

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): Thu Jun 19 21:58:26 EDT 2025
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1277428
======================================================================

  Trigger: 01277428      Segment: 000

  BAT Trigger Time: 757129010.752   [s; MET]
      Trigger Stop: 757129011.776   [s; MET]
               UTC: 2024-12-29T01:36:15.955240    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 274.149125849278   Dec: 74.7138330676705  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    15.88
     Image Trigger?:     NO
     Rate S/N Ratio:     39.7240481320824  [ if not an image trigger ]
     Image S/N Ratio:    15.88

  Flight Position:   [ source = BAT ]
    RA: 274.149125849278   Dec: 74.7138330676705  [deg; J2000]

  Ground Position:   [ source = BAT pre-slew burst ]
    RA: 274.139639422753   Dec: 74.6943037113503  [deg; J2000]  
        { 18h 16m 33.5s , +74d 41' 39.5" }
         +/- 1.22698191870708 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.376325163076137 [arcmin] (formal 1-sigma fit error)
    SNR: 22.709455365888
 
  Angular difference between Flight and Ground position is 1.181343 arcmin
 
  Partial Coding Fraction: 0.3984375    [ including projection effects ]

  Duration
     T90: 5.0479998588562 +/- 0.648752741372382
        Measured from: -2.10799992084503
                   to: 2.93999993801117     [s; relative to TRIGTIME]
     T50: 1.50399994850159 +/- 0.392448801217247
        Measured from: -0.0799999237060547
                   to: 1.42400002479553     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.0559999942779541     
                   to: 0.944000005722046     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -2.6159999370575     
                   to: 3.37999999523163     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.339263   0.496197   0.335499   0.036564
           0.027514   0.029626   0.023916   0.017394 [error]
 Peak      0.122288   0.209274   0.145468   0.025050
           0.012772   0.014730   0.012250   0.007646 [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 1.21e-07 1.97e-07 2.43e-07 5.92e-07 7.32e-07 1.16e-06   erg/cm2
              Error 1.32e-08 1.38e-08 2.28e-08 1.14e-07 5.50e-08 1.34e-07   erg/cm2
Peak flux Power-law 1.42e+00 1.35e+00 8.95e-01 9.21e-01 4.05e+00 4.59e+00   ph/cm2/s
              Error 1.84e-01 1.17e-01 9.21e-02 1.80e-01 3.41e-01 3.81e-01   ph/cm2/s
 
Fluence   Cutoff-PL 1.22e-07 1.65e-07 1.73e-07 4.06e-07 5.72e-07 8.69e-07   erg/cm2
              Error 1.49e-08 1.60e-08 2.20e-08 4.03e-08 5.32e-07 1.01e-07   erg/cm2
Peak flux Cutoff-PL 1.12e+00 1.55e+00 1.03e+00 3.09e-01 3.93e+00 4.01e+00   ph/cm2/s
              Error 2.21e-01 1.53e-01 1.17e-01 1.53e-01 3.47e-01 3.75e-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    1.699    0.115    -      -           1.31e-02 9.48e-04   55.860 57
CPL   0.929    0.505      68.3   22.6      3.28e-02 2.09e-02   47.780 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    1.595    0.126    -      -           3.15e-02 2.68e-03   63.520 57
CPL   0.233    0.670      65.7   12.2      1.54e-01 1.36e-01   47.290 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: 5.184000 sec.
T50 in the 50-300 keV band: 1.792000 sec.

 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100    5.996   -2.616    3.380
T90     5.048   -2.108    2.940
T50     1.504   -0.080    1.424
Peak    1.000   -0.056    0.944

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
  274.1396    74.6943   0.0085    29.9937    69.2012         1.2608474     22.709 TRIG_01277428                 
 
Foreground time interval of the image:
 -2.616   3.380 (delta_t =   5.996 [sec])
Background time interval of the image:
-239.752  -2.616 (delta_t = 237.136 [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

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

8 ms binning

From T100_start-3 s to T100_start+3 s

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

2 ms binning

From T100_start-1 s to T100_start+1 s

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

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   -2.616 sec. to    3.380 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.69867     ( -0.113979   0.11584 )
Norm@50keV  : 1.31473E-02    ( -0.000950409   0.000944974 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   55.86     using 59 bins.
 Reduced chi-squared = 0.98
# Null hypothesis probability of 5.18e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 5.996 sec: 1.74537 ( -0.12275  0.1229 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.30085e-07 ( -5.49018e-08  5.51898e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -2.616 sec. to    3.380 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.928935     ( -0.532836   0.476879 )
Epeak [keV] : 68.2569      ( -11.6996 33.4418 )
Norm@50keV  : 3.27563E-02    ( -0.0138833   0.027953 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.78     using 59 bins.
 Reduced chi-squared = 0.853214
# Null hypothesis probability of 7.75e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 5.996 sec: 1.69556 ( -0.12659  0.12663 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.72073e-07 ( -7.60844e-08  9.87343e-07 ) ergs/cm2

Band function

Time interval is from   -2.616 sec. to    3.380 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]    : 13.7065  (-1.07557  1.16918)
R^2/D10^2   : 0.268826  (-0.0699359   0.0939123)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   85.52     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 8.59e-03 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  6.408e-08   8.823e-09
25- 50  2.333e-07   2.174e-08
50-150  2.854e-07   3.903e-08
15-150  5.828e-07   4.995e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 134.635       (-33.575      47.279)
Norm        : 7.28242       (-0.594519     0.729269)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   49.37     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 7.54e-01 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.131e-07   1.073e-08
25- 50  2.061e-07   2.314e-08
50-150  3.884e-07   1.399e-07
15-150  7.076e-07   1.472e-07

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 6.03606        (-1.44638      1.72145)
R1^2/D10^2  : 2.89227        (-1.6377      5.31722)
kT2 [keV]   : 19.9983        (-2.9392      4.63504)
R2^2/D10^2  : 5.34578E-02    (-0.0309958   0.0497977)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   46.72     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 7.79e-01 with 55 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.094e-07   4.341e-08
25- 50  2.086e-07   5.348e-08
50-150  3.730e-07   1.094e-07
15-150  6.910e-07   1.917e-07

Peak spectrum fit

Power-law model

Time interval is from   -0.056 sec. to    0.944 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.59516     ( -0.12505   0.127357 )
Norm@50keV  : 3.15245E-02    ( -0.00268839   0.00267801 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   63.52     using 59 bins.
 Reduced chi-squared = 1.11439
# Null hypothesis probability of 2.58e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 4.04512 ( -0.34118  0.3415 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.95039e-07 ( -2.65107e-08  2.66454e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.056 sec. to    0.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.232561     ( -0.720352   0.619588 )
Epeak [keV] : 65.6594      ( -8.59534 15.7125 )
Norm@50keV  : 0.153985    ( -0.0777632   0.193792 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.29     using 59 bins.
 Reduced chi-squared = 0.844464
# Null hypothesis probability of 7.90e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 3.93267 ( -0.34682  0.34674 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.82319e-07 ( -2.7278e-08  2.75299e-08 ) ergs/cm2

Band function

Time interval is from   -0.056 sec. to    0.944 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]    : 14.6590  (-1.18639  1.29563)
R^2/D10^2   : 0.536504  (-0.142857   0.190803)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   59.71     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 3.77e-01 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.422e-08   3.340e-09
25- 50  9.420e-08   9.375e-09
50-150  1.363e-07   2.055e-08
15-150  2.547e-07   2.390e-08

Thermal bremsstrahlung (OTTB)

 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 165.151       (-45.3147      -162.422)
Norm        : 17.0347       (-1.53493     1.64399)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   55.61     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 5.27e-01 with 57 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.336e-08   4.820e-09
25- 50  8.146e-08   1.412e-08
50-150  1.671e-07   6.524e-08
15-150  2.919e-07   9.675e-08

Double BB

 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 5.03145        (-2.45281      5.67619)
R1^2/D10^2  : 8.41452        (-7.34079      195.927)
kT2 [keV]   : 17.3181        (-2.28678      9.63953)
R2^2/D10^2  : 0.260488    (-0.229405   0.20571)
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.66     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 7.48e-01 with 55 degrees of freedom
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  3.681e-08   1.568e-08
25- 50  8.498e-08   2.545e-08
50-150  1.536e-07   4.203e-08
15-150  2.754e-07   6.485e-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: 1.69867     ( -0.113979   0.11584 )
Norm@50keV  : 1.31473E-02    ( -0.000950409   0.000944974 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   55.86     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 5.18e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 5.996 sec: 1.74530 ( -0.122739  0.122893 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.29959e-07 ( -5.49386e-08  5.52124e-08 ) ergs/cm2

Cutoff power-law model

Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.928936     ( -0.532837   0.476878 )
Epeak [keV] : 68.2569      ( -11.6996 33.4418 )
Norm@50keV  : 3.27563E-02    ( -0.0138832   0.027953 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.78     using 59 bins.
 Reduced chi-squared = 
# Null hypothesis probability of 7.75e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 5.996 sec: 1.69534 ( -0.12655  0.12658 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.9839e-07 ( -5.81672e-08  5.85929e-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)  = 1.97e-07
S(50-100 keV) = 2.43e-07

T90 vs. Hardness ratio plot

T90                                   = 5.0479998588562 sec.
Hardness ratio (energy fluence ratio) = 1.2335

Color vs. Color plot

Count Ratio  (25-50 keV) / (15-25 keV) = 1.46257
Count Ratio (50-100 keV) / (15-25 keV) = 0.988905

Mask shadow pattern

IMX = 2.049574936706344E-01, IMY = -5.395893732863686E-01

TIME vs. PHA plot around the trigger time

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

TIME vs. DetID plot around the trigger time

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

100 us light curve (15-350 keV)

Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 1.024000

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:
-239.752000 -2.616000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.4555  35.3537    3.8  34.1  -11.9   1.2220   3.0    0.7	Her X-1                       
288.9228  10.9640    6.9  36.3  -83.8  -1.3200  -1.7    7.4	GRS 1915+105                  
299.6252  35.2326    2.2  11.3 -106.3   1.6965   5.3    2.5	Cyg X-1                       
308.1204  41.0329    2.3   9.2 -156.1   1.5295   4.9    4.8	Cyg X-3                       
325.9190  38.2689    0.0  22.2 -177.0  -0.7000  -2.1   12.3	Cyg X-2                       
224.1432  31.4854    3.4  57.0    4.2   4.3869   3.4 ------	UNKNOWN                       
329.2456  37.3338    3.0  24.9 -178.4   1.2384   3.8 ------	UNKNOWN                       
271.5645   7.6600    2.8  44.9  -60.2   5.9673   4.1 ------	UNKNOWN

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

Time interval of the image:
-2.616000 3.380000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.2458  35.3690   25.5  34.2  -11.7   0.0178   0.5   10.5	Her X-1                       
288.6729  10.9011    5.6  36.4  -83.4   0.1417   2.1    7.9	GRS 1915+105                  
299.4442  35.3733    0.0  11.2 -105.6   0.0471   1.4   12.5	Cyg X-1                       
308.2237  40.7749    5.1   9.5 -155.2  -0.0687  -2.2   11.8	Cyg X-3                       
326.1671  38.4805    4.8  22.3 -177.8   0.0774   2.4    9.5	Cyg X-2                       
274.1397  74.6943    0.5  30.0   69.2   1.2608  22.7 ------	UNKNOWN                       
271.6762   7.5986    2.8  44.9  -60.4   0.4510   4.2 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:

Plot creation:
Fri Jun 20 01:57:30 EDT 2025