GRB220930A: Summary Image Light curves Spectra Distribution Others

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: Wed Jun 14 12:22:37 EDT 2023
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1125809
======================================================================

  Trigger: 01125809      Segment: 000

  BAT Trigger Time: 686229142.08   [s; MET]
      Trigger Stop: 686229143.104   [s; MET]
               UTC: 2022-09-30T11:11:52.128760    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 64.7373600672291   Dec: 13.3517442973112  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.33
     Image Trigger?:     NO
     Rate S/N Ratio:     41.206795556073  [ if not an image trigger ]
     Image S/N Ratio:    7.33

  Analysis Position:   [ source = BAT ]
    RA: 64.7373600672291   Dec: 13.3517442973112  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 64.7278987133664   Dec: 13.3505427647535  [deg; J2000]  
        { 04h 18m 54.7s , +13d 21' 02.0" }
         +/- 1.67469535989671 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.733363629102995 [arcmin] (formal 1-sigma fit error)
    SNR: 14.5616326220971
 
  Angular difference between the analysis and refined position is 0.557023 arcmin
 
  Partial Coding Fraction: 0.1103516    [ including projection effects ]

  Duration
     T90: 182.095999956131 +/- 95.8901187601642
        Measured from: -1.30400002002716
                   to: 180.791999936104     [s; relative to TRIGTIME]
     T50: 60.864000082016 +/- 22.9323331127479
        Measured from: 1.49599993228912
                   to: 62.3600000143051     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.484000086784363     
                   to: 0.515999913215637     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -3.41600000858307     
                   to: 224.199999928474     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.915492   3.265906   2.505995   0.753369
           0.196245   0.207046   0.185951   0.154441 [error]
 Peak      0.131604   0.289576   0.268082   0.122741
           0.032331   0.037352   0.037634   0.030254 [error]

     [ fluence units of on-axis counts / fully illuminated detector ] 

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  227.616   -3.416  224.200
T90   182.096   -1.304  180.792
T50    60.864    1.496   62.360
Peak    1.000   -0.484    0.516
 
 
====== 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      -1.480    -0.121      0.121       -           -               -         2.70e-03     -1.92e-04          1.92e-04      54.180   57
CPL     -1.171    -0.368      0.527      139.202     -58.184      -139.202      3.83e-03     -1.27e-03          3.05e-03      52.950   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
 
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      -1.290     -0.257     0.261       -           -               -         5.05e-02     -7.89e-03          7.87e-03      73.830   57
CPL     -0.836     -0.589     1.325      143.030    -143.030      -143.030      8.22e-02     -3.84e-02          2.43e-01      73.340   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   7.70e-07  1.43e-06  2.05e-06  6.23e-06  5.84e-06  1.05e-05   erg/cm2
      90%_error_low -9.59e-08 -1.11e-07 -1.81e-07 -1.11e-06 -4.45e-07 -1.25e-06   erg/cm2
      90%_error_hi   9.95e-08  1.11e-07  1.80e-07  1.26e-06  4.47e-07  1.37e-06   erg/cm2
Peak flux       PL   1.70e+00  1.94e+00  1.59e+00  2.17e+00  6.02e+00  7.40e+00   ph/cm2/s
      90%_error_low -4.82e-01 -3.65e-01 -2.77e-01 -6.92e-01 -9.92e-01 -1.16e+00   ph/cm2/s
      90%_error_hi   5.30e-01  3.57e-01  2.72e-01  8.54e-01  9.97e-01  1.17e+00   ph/cm2/s
 
Fluence        CPL   7.28e-07  1.48e-06  2.11e-06  4.02e-06  5.74e-06  8.33e-06   erg/cm2
      90%_error_low -1.15e-07 -1.31e-07 -2.01e-07 -1.88e-06 -4.80e-07 -1.91e-06   erg/cm2
      90%_error_hi   1.17e-07  1.35e-07  2.05e-07  2.58e-06  4.76e-07  2.70e-06   erg/cm2
Peak flux      CPL   1.53e+00  2.01e+00  1.68e+00  1.42e+00  5.94e+00  6.65e+00   ph/cm2/s
      90%_error_low -5.96e-01 -4.00e-01 -3.45e-01     N/A   -1.01e+00 -1.42e+00   ph/cm2/s
      90%_error_hi   6.44e-01  4.17e-01  3.66e-01     N/A    1.02e+00  1.76e+00   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   64.7279    13.3505   0.0133    50.5685    15.9005         5.0384774     14.562 TRIG_01125809                 
 
Foreground time interval of the image:
 -3.416  15.421 (delta_t =  18.837 [sec])
Background time interval of the image:
-68.379  -3.416 (delta_t =  64.963 [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

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   -3.416 sec. to  224.200 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.48018     ( -0.121448   0.12138 )
Norm@50keV  : 2.69768E-03    ( -0.000192386   0.00019209 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   54.18     using 59 bins.
 Reduced chi-squared = 0.950526
# Null hypothesis probability of 5.82e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 227.6 sec: 0.335021 ( -0.024981  0.025039 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.8447e-06 ( -4.45092e-07  4.47061e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -3.416 sec. to  224.200 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.17107     ( -0.368061   0.527404 )
Epeak [keV] : 139.202      ( -58.1872 -139.205 )
Norm@50keV  : 3.83306E-03    ( -0.00126577   0.00304799 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   52.95     using 59 bins.
 Reduced chi-squared = 0.945536
# Null hypothesis probability of 5.91e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 227.6 sec: 0.330833 ( -0.025795  0.025823 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.74107e-06 ( -4.80509e-07  4.76089e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   -0.484 sec. to    0.516 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.2899     ( -0.257337   0.261477 )
Norm@50keV  : 5.05418E-02    ( -0.00788832   0.00787258 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   73.83     using 59 bins.
 Reduced chi-squared = 1.29526
# Null hypothesis probability of 6.63e-02 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 6.01876 ( -0.9924  0.99734 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.00749e-07 ( -8.21193e-08  8.23603e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.484 sec. to    0.516 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.83646     ( -0.589216   1.32504 )
Epeak [keV] : 143.030      ( -143.064 -143.064 )
Norm@50keV  : 8.22138E-02    ( -0.038411   0.24284 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   73.34     using 59 bins.
 Reduced chi-squared = 1.30964
# Null hypothesis probability of 5.99e-02 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 5.93543 ( -1.01063  1.01645 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.93696e-07 ( -8.64095e-08  8.47729e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 182.096 sec.
Hardness ratio (energy fluence ratio) = 1.4338050722

S(15-50 keV) vs. S(50-150 keV) plot

S(15-50 keV)  = 2.2009483e-06
S(50-150 keV) = 3.643864e-06

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 = 1.169526350298008E+00, IMY = -3.331601940831920E-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:
-68.379400 -3.416000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
326.1675  38.3219   56.1  39.2 -145.5   0.0418   0.2    0.2	Cyg X-2                       
 16.3491  -4.9384    2.6  34.6   92.5   1.3949   4.4 ------	UNKNOWN                       
 43.5715  39.7558    2.4  27.2  -21.5   0.6487   4.8 ------	UNKNOWN                       
338.1355  47.3097    3.4  32.0 -127.7   0.6256   3.4 ------	UNKNOWN                       
308.8763  41.6273    2.0  52.1 -139.3   3.5199   5.7 ------	UNKNOWN                       
 57.4781  66.3005    2.2  45.6  -57.8   3.1464   5.1 ------	UNKNOWN                       

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

Time interval of the image:
-3.416000 15.420600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
326.1782  38.3260   65.8  39.2 -145.5   0.0180   0.2    0.4	Cyg X-2                       
340.3496  -9.0510    2.3  49.6  142.9   1.5723   5.0 ------	UNKNOWN                       
 64.7279  13.3506    0.8  50.6   15.9   5.0373  14.6 ------	UNKNOWN                       
319.9749  22.8146    2.6  47.4 -166.3   0.5719   4.5 ------	UNKNOWN                       
313.0898  26.8842    2.6  52.0 -158.6   0.8428   4.4 ------	UNKNOWN                       
346.7231  67.4966    3.1  41.0  -95.9   1.0655   3.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
156.820600 717.858300
720.920000 963.110800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6218  22.0320    0.5  20.0 -113.2  31.3247  23.4    1.2	Crab                          
104.8092  -8.8654    2.8  45.6  -57.8  25.3233   4.1 ------	UNKNOWN