GRB200919A: 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 Oct 19 23:42:05 EDT 2022
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger996503
======================================================================

  Trigger: 00996503      Segment: 000

  BAT Trigger Time: 622173166.592   [s; MET]
      Trigger Stop: 622173170.688   [s; MET]
               UTC: 2020-09-19T01:52:20.932860    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 168.915726722106   Dec: 32.4569651703903  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.51
     Image Trigger?:     NO
     Rate S/N Ratio:     14.456832294801  [ if not an image trigger ]
     Image S/N Ratio:    9.51

  Analysis Position:   [ source = BAT ]
    RA: 168.915726722106   Dec: 32.4569651703903  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 168.898720778248   Dec: 32.4534957566324  [deg; J2000]  
        { 11h 15m 35.7s , +32d 27' 12.6" }
         +/- 1.47766268218705 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.576664110169208 [arcmin] (formal 1-sigma fit error)
    SNR: 17.4127732051079
 
  Angular difference between the analysis and refined position is 0.885795 arcmin
 
  Partial Coding Fraction: 0.625    [ including projection effects ]

  Duration
     T90: 108.432000041008 +/- 21.5348603229185
        Measured from: -56.8079999685287
                   to: 51.6240000724792     [s; relative to TRIGTIME]
     T50: 27.8400000333786 +/- 9.0282258569339
        Measured from: -17.5440000295639
                   to: 10.2960000038147     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.03600001335144     
                   to: 2.03600001335144     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -61.4639999866486     
                   to: 70.5039999485016     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.580862   1.527997   0.565105   0.342199
           0.095365   0.097758   0.086811   0.082105 [error]
 Peak      0.056943   0.060210   0.031821   0.003747
           0.008891   0.009433   0.008329   0.007047 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  131.968  -61.464   70.504
T90   108.432  -56.808   51.624
T50    27.840  -17.544   10.296
Peak    1.000    1.036    2.036
 
 
====== 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: 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      -2.247    -0.170      0.162       -           -               -         1.50e-03     -1.73e-04          1.70e-04      58.760   57
CPL     -2.237    -0.299      0.152     9999.360      N/A           N/A         1.51e-03        N/A               N/A         58.780   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      -1.825     -0.302     0.279       -           -               -         9.05e-03     -1.90e-03          1.86e-03      58.540   57
CPL     -0.353     -1.226     1.683       47.032     -11.653        33.750      6.41e-02     -6.41e-02          5.80e-01      54.110   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   5.12e-07  5.99e-07  5.04e-07  7.19e-07  1.87e-06  2.33e-06   erg/cm2
      90%_error_low -5.46e-08 -4.91e-08 -7.90e-08 -1.97e-07 -1.79e-07 -3.01e-07   erg/cm2
      90%_error_hi   5.55e-08  4.89e-08  8.20e-08  2.46e-07  1.83e-07  3.37e-07   erg/cm2
Peak flux       PL   5.09e-01  4.23e-01  2.39e-01  2.00e-01  1.26e+00  1.37e+00   ph/cm2/s
      90%_error_low -1.19e-01 -7.37e-02 -6.29e-02 -8.42e-02 -2.19e-01 -2.45e-01   ph/cm2/s
      90%_error_hi   1.24e-01  7.37e-02  6.43e-02  1.14e-01  2.19e-01  2.47e-01   ph/cm2/s
 
Fluence        CPL   5.00e-07  5.79e-07  5.00e-07  3.72e-07  1.81e-06  1.97e-06   erg/cm2
      90%_error_low -4.58e-08 -1.17e-08 -3.64e-08 -2.73e-07 -1.94e-07 -3.70e-07   erg/cm2
      90%_error_hi   5.81e-08  8.55e-08  7.43e-08  2.81e-07  2.04e-07  4.43e-07   erg/cm2
Peak flux      CPL   4.46e-01  5.05e-01  2.37e-01  3.99e-02  1.22e+00  1.23e+00   ph/cm2/s
      90%_error_low -1.35e-01 -1.00e-01 -8.47e-02 -3.99e-02 -2.18e-01 -2.22e-01   ph/cm2/s
      90%_error_hi   1.38e-01  1.06e-01  7.88e-02  1.10e-01  2.19e-01  2.30e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  168.8987    32.4535   0.0110    25.2528  -120.9612         4.1893369     17.413 TRIG_00996503                 
 
Foreground time interval of the image:
-61.464  70.504 (delta_t = 131.968 [sec])
Background time interval of the image:
-239.592 -61.464 (delta_t = 178.128 [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  -61.464 sec. to   70.504 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.24727     ( -0.169846   0.162086 )
Norm@50keV  : 1.49768E-03    ( -0.000172585   0.000170176 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   58.76     using 59 bins.
 Reduced chi-squared = 1.03088
# Null hypothesis probability of 4.11e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 132 sec: 0.254300 ( -0.019897  0.0199 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.87242e-06 ( -1.78651e-07  1.83015e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -61.464 sec. to   70.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.23673     ( -0.295839   0.155172 )
Epeak [keV] : 9999.36      (   )
Norm@50keV  : 1.50910E-03    (     )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   58.77     using 59 bins.
 Reduced chi-squared = 1.04946
# Null hypothesis probability of 3.74e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 132 sec: 0.251149 ( -0.019426  0.019793 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.80573e-06 ( -1.94258e-07  2.03516e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.036 sec. to    2.036 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.82478     ( -0.301435   0.279408 )
Norm@50keV  : 9.05201E-03    ( -0.00190418   0.00185915 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   58.54     using 59 bins.
 Reduced chi-squared = 1.02702
# Null hypothesis probability of 4.19e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 1.25960 ( -0.21941  0.21941 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.32818e-08 ( -1.73022e-08  1.78435e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.036 sec. to    2.036 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.352848     ( -1.22556   1.6833 )
Epeak [keV] : 47.0320      ( -11.6526 33.7496 )
Norm@50keV  : 6.40774E-02    ( -0.0640766   0.579892 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   54.11     using 59 bins.
 Reduced chi-squared = 0.96625
# Null hypothesis probability of 5.47e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 1.22302 ( -0.21797  0.21946 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.44132e-08 ( -1.67671e-08  1.86076e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = N/A sec.
Hardness ratio (energy fluence ratio) = N/A

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

S(15-50 keV)  = N/A
S(50-150 keV) = N/A

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 = -2.426649597517645E-01, IMY = 4.044829706038347E-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:
-239.592000 -61.464000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 98.6128  49.9027    2.7  32.2  100.1   1.5220   4.2 ------	UNKNOWN                       
109.5692  70.3693    5.5  38.2  135.7   1.0265   2.1 ------	UNKNOWN                       
111.9821  28.0213    2.8  23.7   50.2   1.0156   4.1 ------	UNKNOWN                       
176.9736  61.3118    2.7  35.4 -178.0   1.1731   4.3 ------	UNKNOWN                       
138.2139  14.9667    2.5  20.5  -28.1   0.9415   4.6 ------	UNKNOWN                       

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

Time interval of the image:
-61.464000 70.504000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
168.8988  32.4535    0.7  25.3 -121.0   4.1894  17.4 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
603.708610 962.447300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.6232  35.3068  672.4  26.8 -176.5   0.0066   0.0    8.4	Her X-1                       
299.6547  35.0343    0.0  38.3  115.3   1.9148   1.9   10.5	Cyg X-1                       
308.1931  41.0571    4.5  37.2  100.7   2.1159   2.5    7.3	Cyg X-3                       
269.4817  84.6411    2.4  22.8    4.5   1.6423   4.9 ------	UNKNOWN                       
102.6636  68.6382    3.1  47.9  -11.5   2.4258   3.7 ------	UNKNOWN                       
102.7905  60.0066    3.8  56.2  -14.6   3.9450   3.0 ------	UNKNOWN                       
111.7175  60.5073    2.6  54.4  -19.5   4.9879   4.4 ------	UNKNOWN                       
127.7772  62.5239    2.9  49.4  -27.3   3.4056   4.0 ------	UNKNOWN                       
211.7355  28.4735    2.9  44.2 -117.3   5.5281   4.0 ------	UNKNOWN