Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Tue Oct  8 22:17:34 EDT 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger922968
======================================================================

  Trigger: 00922968      Segment: 000

  BAT Trigger Time: 588801428.096   [s; MET]
      Trigger Stop: 588801429.12   [s; MET]
               UTC: 2019-08-29T19:56:44.601720    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 44.5397196710187   Dec: -8.96781199714715  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.51
     Image Trigger?:     NO
     Rate S/N Ratio:     23.7065391822594  [ if not an image trigger ]
     Image S/N Ratio:    8.51

  Analysis Position:   [ source = BAT ]
    RA: 44.5397196710187   Dec: -8.96781199714715  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 44.5418653954335   Dec: -8.95789022098407  [deg; J2000]
        { 02h 58m 10.0s , -08d 57' 28.4" }
         +/- 1.9303553917174 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.968985195904689 [arcmin] (formal 1-sigma fit error)
    SNR: 11.886804852414
 
  Angular difference between the analysis and refined position is 0.61 arcmin
 
  Partial Coding Fraction: 0.04248047    [ including projection effects ]

  Duration
     T90: 56.8959999084473 +/- 47.0011049601117
        Measured from: -50.5519999265671
                   to: 6.34399998188019     [s; relative to TRIGTIME]
     T50: 4.28799986839294 +/- 1.31784066564192
        Measured from: -1.71999990940094
                   to: 2.567999958992     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.0119999647140503     
                   to: 0.98800003528595     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -51.8959999084473     
                   to: 7.24000000953674     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     4.596365   4.613677   1.547082  -0.122486
           0.382614   0.391842   0.333390   0.318171 [error]
 Peak      0.816761   0.588829   0.174093   0.033045
           0.088826   0.082323   0.054750   0.043576 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   59.136  -51.896    7.240
T90    56.896  -50.552    6.344
T50     4.288   -1.720    2.568
Peak    1.000   -0.012    0.988
 
 
====== 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      -2.564    -0.222      0.205       -           -               -         1.06e-02     -1.64e-03          1.62e-03      52.980   57
CPL     -1.370    -0.641      1.577       18.898      N/A           N/A         5.95e-02        N/A               N/A         49.250   56
 
 
=== 1-s peak 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      -3.232     -0.360     0.302       -           -               -         5.50e-02     -1.49e-02          1.48e-02      58.280   57
CPL     -1.000      N/A       N/A          80.000      N/A           N/A         1.07e-01        N/A               N/A        131.660   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   2.19e-06  2.12e-06  1.44e-06  1.52e-06  6.37e-06  7.28e-06   erg/cm2
      90%_error_low -2.85e-07 -2.28e-07 -2.95e-07 -5.24e-07 -7.16e-07 -9.91e-07   erg/cm2
      90%_error_hi   2.91e-07  2.26e-07  3.10e-07  6.86e-07  7.29e-07  1.09e-06   erg/cm2
Peak flux       PL   1.23e+01  4.56e+00  9.70e-01  2.46e-01  1.80e+01  1.81e+01   ph/cm2/s
      90%_error_low -2.18e+00 -7.99e-01 -3.20e-01 -1.21e-01 -2.72e+00 -2.73e+00   ph/cm2/s
      90%_error_hi   2.23e+00  7.75e-01  3.44e-01  1.72e-01  2.73e+00  2.73e+00   ph/cm2/s
 
Fluence        CPL    N/A      N/A      N/A      N/A      N/A      N/A      erg/cm2
      90%_error_low -2.85e-07 -2.28e-07 -2.95e-07 -5.24e-07 -7.16e-07 -9.91e-07   erg/cm2
      90%_error_hi   2.91e-07  2.26e-07  3.10e-07  6.86e-07  7.29e-07  1.09e-06   erg/cm2
Peak flux      CPL     N/A      N/A      N/A      N/A      N/A      N/A     ph/cm2/s
      90%_error_low -2.18e+00 -7.99e-01 -3.20e-01 -1.21e-01 -2.72e+00 -2.73e+00   ph/cm2/s
      90%_error_hi   2.23e+00  7.75e-01  3.44e-01  1.72e-01  2.73e+00  2.73e+00   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
   44.5419    -8.9579   0.0161    53.0564   169.5545        11.4549532     11.887 TRIG_00922968                 
 
Foreground time interval of the image:
-51.896  12.005 (delta_t =  63.901 [sec])
Background time interval of the image:
-153.795 -51.896 (delta_t = 101.899 [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  -51.896 sec. to    7.240 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.56418     ( -0.221602   0.205265 )
Norm@50keV  : 1.05722E-02    ( -0.00163808   0.00161571 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.98 using 59 PHA bins.
# Reduced chi-squared =         0.9295 for     57 degrees of freedom 
# Null hypothesis probability =   6.265477e-01
 
Photon flux (15-150 keV)    in 59.14 sec: 2.16162 ( -0.21713  0.21736 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.36796e-06 ( -7.16233e-07  7.29149e-07 ) ergs/cm2
    Cutoff power-law model
    Time interval is from  -51.896 sec. to    7.240 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.36963     ( -0.642839   1.57487 )
Epeak [keV] : 18.8978      (   )
Norm@50keV  : 5.94836E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.25 using 59 PHA bins.
# Reduced chi-squared =         0.8794 for     56 degrees of freedom 
# Null hypothesis probability =   7.264320e-01
 
Photon flux (15-150 keV)    in 59.14 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from   -0.012 sec. to    0.988 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -3.23166     ( -0.360041   0.301917 )
Norm@50keV  : 5.50036E-02    ( -0.0149091   0.0147579 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.28 using 59 PHA bins.
# Reduced chi-squared =          1.022 for     57 degrees of freedom 
# Null hypothesis probability =   4.281806e-01
 
Photon flux (15-150 keV)    in 1 sec: 17.9964 ( -2.7245  2.7275 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.42027e-07 ( -1.16926e-07  1.17659e-07 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -0.012 sec. to    0.988 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1     (       )
Epeak [keV] : 80.0000      (   )
Norm@50keV  : 0.106818    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =         131.66 using 59 PHA bins.
# Reduced chi-squared =         2.3510 for     56 degrees of freedom 
# Null hypothesis probability =   4.936829e-08
 
Photon flux (15-150 keV)    in 1 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 56.896 sec.
Hardness ratio (energy fluence ratio) = 0.676394318463

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

    S(15-50 keV)  = 4.317136e-06
S(50-150 keV) = 2.0509393e-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 = -1.307727448355517E+00, IMY = -2.410857632435768E-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:
-153.795410 -51.896000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
342.9171 -29.1791    2.4  39.3   81.9   4.0342   4.8 ------	UNKNOWN                       
338.3553 -30.9460    2.4  39.9   75.2   4.5459   4.8 ------	UNKNOWN                       
 27.1653 -14.1734    2.4  44.9  148.5   4.4040   4.8 ------	UNKNOWN                       
303.6921 -50.3429    2.5  42.9   25.7   1.8258   4.6 ------	UNKNOWN                       
 16.5381 -48.7423    2.4  10.4  124.0   1.1339   4.9 ------	UNKNOWN                       
 65.4878 -32.7404    2.4  39.5 -151.7   1.6657   4.8 ------	UNKNOWN                       
 89.7463 -72.3481    2.8  29.3  -75.6   1.2521   4.1 ------	UNKNOWN                       
 86.3455 -61.0966    2.7  31.5  -97.7   1.4761   4.3 ------	UNKNOWN

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

    Time interval of the image:
-51.896000 7.240000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 44.5426  -8.9549    1.1  53.1  169.6  11.3343  11.0 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
86.004600 662.984000
720.904000 963.024000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 23.7252  28.2696    3.0  42.3  158.7  14.8415   3.8 ------	UNKNOWN                       
 53.9167  29.3317    3.5  39.4 -160.7   7.8039   3.3 ------	UNKNOWN                       
 66.2059 -12.7564    2.3  21.6  -71.7   8.9953   4.9 ------	UNKNOWN                       
 74.6902  -9.1561    2.6  29.8  -80.9   9.6354   4.4 ------	UNKNOWN