Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.47
    Process Start Time: Mon May 18 14:45:32 EDT 2020
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger956824
======================================================================

  Trigger: 00956824      Segment: 000

  BAT Trigger Time: 603552778.304   [s; MET]
      Trigger Stop: 603552778.816   [s; MET]
               UTC: 2020-02-16T13:32:33.858540    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 160.460729941118   Dec: 19.4541045214607  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.23
     Image Trigger?:     NO
     Rate S/N Ratio:     15.1657508881031  [ if not an image trigger ]
     Image S/N Ratio:    8.23

  Analysis Position:   [ source = BAT ]
    RA: 160.460729941118   Dec: 19.4541045214607  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 160.454200385875   Dec: 19.4711343785963  [deg; J2000]  
        { 10h 41m 49.0s , +19d 28' 16.1" }
         +/- 0.930348304476157 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.254245413202635 [arcmin] (formal 1-sigma fit error)
    SNR: 33.721774674736
 
  Angular difference between the analysis and refined position is 1.086510 arcmin
 
  Partial Coding Fraction: 0.84375    [ including projection effects ]

  Duration
     T90: 67.4479998350143 +/- 6.56804386229279
        Measured from: 0.48800003528595
                   to: 67.9359998703003     [s; relative to TRIGTIME]
     T50: 38.1959999799728 +/- 5.19073182678569
        Measured from: 4.04799997806549
                   to: 42.2439999580383     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 2.80400002002716     
                   to: 3.80400002002716     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.720000028610229     
                   to: 79.7200000286102     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.964773   1.285195   0.662680   0.083340
           0.052608   0.054789   0.046636   0.039026 [error]
 Peak      0.039480   0.075597   0.064275   0.013460
           0.006655   0.007643   0.006608   0.004939 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   80.440   -0.720   79.720
T90    67.448    0.488   67.936
T50    38.196    4.048   42.244
Peak    1.000    2.804    3.804
 
 
====== 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: CPL)
 
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      -1.850    -0.098      0.096       -           -               -         2.29e-03     -1.41e-04          1.40e-04      71.150   57
CPL     -0.658    -0.469      0.527       49.722      -5.040         7.234      1.03e-02     -4.58e-03          9.73e-03      49.010   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: CPL)
 
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      -1.350     -0.174     0.174       -           -               -         1.27e-02     -1.42e-03          1.41e-03      59.380   57
CPL     -0.118     -0.819     0.997       77.718     -15.673        54.189      5.26e-02     -3.17e-02          1.06e-01      52.300   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   3.28e-07  4.87e-07  5.40e-07  1.13e-06  1.70e-06  2.48e-06   erg/cm2
      90%_error_low -2.68e-08 -2.63e-08 -4.46e-08 -1.79e-07 -1.04e-07 -2.25e-07   erg/cm2
      90%_error_hi   2.73e-08  2.64e-08  4.49e-08  2.00e-07  1.05e-07  2.41e-07   erg/cm2
Peak flux       PL   4.54e-01  5.00e-01  3.92e-01  5.07e-01  1.54e+00  1.85e+00   ph/cm2/s
      90%_error_low -8.25e-02 -6.02e-02 -5.18e-02 -1.22e-01 -1.72e-01 -2.10e-01   ph/cm2/s
      90%_error_hi   8.65e-02  5.97e-02  5.14e-02  1.42e-01  1.72e-01  2.12e-01   ph/cm2/s
 
Fluence        CPL   2.83e-07  5.50e-07  5.29e-07  2.33e-07  1.53e-06  1.59e-06   erg/cm2
      90%_error_low -3.17e-08 -3.56e-08 -5.44e-08 -9.81e-08 -1.14e-07 -1.50e-07   erg/cm2
      90%_error_hi   3.20e-08  3.63e-08  5.30e-08  1.66e-07  1.18e-07  1.97e-07   erg/cm2
Peak flux      CPL   3.63e-01  5.61e-01  4.38e-01  1.71e-01  1.48e+00  1.53e+00   ph/cm2/s
      90%_error_low -9.95e-02 -7.50e-02 -6.29e-02 -8.60e-02 -1.76e-01 -1.98e-01   ph/cm2/s
      90%_error_hi   1.04e-01  7.76e-02  6.45e-02  1.67e-01  1.76e-01  2.23e-01   ph/cm2/s
 
======================================================================
  • Special notes of this burst




    Image

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

    #   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
      160.4542    19.4711   0.0057    23.2705    30.0367         1.5265929     33.722 TRIG_00956824                 
     
    Foreground time interval of the image:
     -0.720   9.997 (delta_t =  10.717 [sec])
    Background time interval of the image:
    -239.304  -0.720 (delta_t = 238.584 [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

    Bokeh Plot

    Other quick-look light curves:




    Spectra

    Notes:

    Time averaged spectrum fit using the average DRM

    Power-law model
    Time interval is from   -0.720 sec. to   79.720 sec.
    XSPEC12>exit
     XSPEC: quit
     
     
    Photon index: -1.85002     ( -0.0975652   0.0957537 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 1.85002     ( -0.0957537   0.0975652 )
    Norm@50keV  : 2.29378E-03    ( -0.000141019   0.000139955 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 80.44 sec: 0.322436 ( -0.017733  0.017748 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.69681e-06 ( -1.04447e-07  1.05345e-07 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from   -0.720 sec. to   79.720 sec.
     XSPEC: quit
     
     
    Photon index: -0.657683     ( -0.469126   0.52667 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.657683     ( -0.52667   0.469126 )
    Epeak [keV] : 49.7219      ( -5.03991 7.23416 )
    Norm@50keV  : 1.03498E-02    ( -0.0045772   0.009729 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 80.44 sec: 0.305269 ( -0.01873  0.018764 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.52733e-06 ( -1.14201e-07  1.18071e-07 ) ergs/cm2
     
    

    1-s peak spectrum fit

    Power-law model
    Time interval is from    2.804 sec. to    3.804 sec.
    XSPEC12>exit
     XSPEC: quit
     
     
    Photon index: -1.34952     ( -0.173759   0.1736 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 1.34952     ( -0.1736   0.173759 )
    Norm@50keV  : 1.27463E-02    ( -0.00141608   0.00141378 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 1 sec: 1.53543 ( -0.17182  0.17201 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.24517e-07 ( -1.51642e-08  1.52743e-08 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from    2.804 sec. to    3.804 sec.
     XSPEC: quit
     
     
    Photon index: -0.118322     ( -0.818952   0.997352 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.118322     ( -0.997352   0.818952 )
    Epeak [keV] : 77.7184      ( -15.6731 54.1886 )
    Norm@50keV  : 5.26209E-02    ( -0.0316642   0.106226 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 1 sec: 1.48452 ( -0.17624  0.17597 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.16356e-07 ( -1.5973e-08  1.62735e-08 ) ergs/cm2
     
    

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot

    T90                                   = 67.448 sec.
    Hardness ratio (energy fluence ratio) = 0.96190006244
    

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

    S(15-50 keV)  = 8.329238e-07
    S(50-150 keV) = 6.944089e-07
    

    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 = 3.723024656157209E-01, IMY = -2.152670034882408E-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:
    -239.304000 -0.720000
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    172.3103  -3.3751    2.8  41.2   66.1   3.2075   4.1 ------	UNKNOWN                       
    102.8085 -27.5856    3.1  55.1  166.0   4.1888   3.7 ------	UNKNOWN                       
    196.6976  39.7878    2.7  56.8    2.9   4.6451   4.3 ------	UNKNOWN                       
    194.1945  43.3825    3.5  55.3   -1.7   2.1625   3.3 ------	UNKNOWN                       
    143.2830  31.8411    2.5  16.1  -27.7   0.9107   4.7 ------	UNKNOWN                       
    190.6426  62.5505    2.5  58.9  -24.3   6.2110   4.7 ------	UNKNOWN                       
    157.0323  65.7721    4.7  50.6  -39.4   1.9451   2.4 ------	UNKNOWN                       
    

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

    Time interval of the image:
    -0.720000 9.996600
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    160.4542  19.4711    0.3  23.3   30.0   1.5266  33.7 ------	UNKNOWN                       
    111.5115  -4.3653    2.3  32.4 -179.7   0.2457   5.0 ------	UNKNOWN                       
    115.1748  46.6379    2.1  34.2  -76.1   0.4114   5.5 ------	UNKNOWN                       
    185.6749  64.5646    2.1  57.9  -27.6   1.4022   5.4 ------	UNKNOWN                       
     83.1119  12.7755    2.7  51.2 -137.5   0.9302   4.4 ------	UNKNOWN                       
    

    Post-slew image of 15-350 keV band

    Time interval of the image:
    101.196630 962.795000
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    127.1779   6.2230    3.3  34.9  104.8   4.0099   3.5 ------	UNKNOWN                       
    109.8720  44.3805    3.0  48.6  165.2   7.9143   3.9 ------	UNKNOWN                       
    207.6703  -0.9165    2.9  50.6  -39.3   9.2899   3.9 ------	UNKNOWN                       
    191.0680  62.5596    2.2  48.0 -129.1  13.2917   5.2 ------	UNKNOWN