Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Wed Aug  2 14:55:19 EDT 2017
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger761622
======================================================================

  Trigger: 00761622      Segment: 000

  BAT Trigger Time: 521504444.736   [s; MET]
      Trigger Stop: 521504445.76   [s; MET]
               UTC: 2017-07-11T22:20:25.381520    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 45.7863907537336   Dec: 47.8503120698934  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    21.47
     Image Trigger?:     NO
     Rate S/N Ratio:     72.5396443332885  [ if not an image trigger ]
     Image S/N Ratio:    21.47

  Analysis Position:   [ source = BAT ]
    RA: 45.7863907537336   Dec: 47.8503120698934  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 45.7782068199629   Dec: 47.8444333310706  [deg; J2000]  
        { 03h 03m 06.8s , +47d 50' 40.0" }
         +/- 0.992093265132614 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.335960524200672 [arcmin] (formal 1-sigma fit error)
    SNR: 30.7640407509617
 
  Angular difference between the analysis and refined position is 0.482711 arcmin
 
  Partial Coding Fraction: 1.015625    [ including projection effects ]

  Duration
     T90: 31.2119999527931 +/- 7.39057671365112
        Measured from: -22.160000026226
                   to: 9.05199992656708     [s; relative to TRIGTIME]
     T50: 3.24799996614456 +/- 0.509886220615425
        Measured from: -0.00400000810623169
                   to: 3.24399995803833     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.0239999890327454     
                   to: 1.02399998903275     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -31.6240000128746     
                   to: 15.3679999709129     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.812235   0.987042   0.587895   0.115921
           0.038617   0.040534   0.035515   0.031591 [error]
 Peak      0.170075   0.230979   0.161932   0.023762
           0.008043   0.008818   0.007702   0.005455 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   46.992  -31.624   15.368
T90    31.212  -22.160    9.052
T50     3.248   -0.004    3.244
Peak    1.000    0.024    1.024
 
 
====== 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      -1.741    -0.096      0.095       -           -               -         3.22e-03     -1.77e-04          1.76e-04      59.810   57
CPL     -1.452    -0.331      0.409       86.957     -27.512       -86.957      4.60e-03     -1.48e-03          2.96e-03      58.070   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      -1.604     -0.081     0.080       -           -               -         3.69e-02     -1.74e-03          1.74e-03      47.940   57
CPL     -1.110     -0.323     0.348       89.866     -18.894        72.503      6.55e-02     -2.01e-02          3.17e-02      40.880   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   2.42e-07  3.85e-07  4.60e-07  1.07e-06  1.40e-06  2.16e-06   erg/cm2
      90%_error_low -1.98e-08 -1.94e-08 -3.48e-08 -1.62e-07 -8.01e-08 -1.94e-07   erg/cm2
      90%_error_hi   2.03e-08  1.94e-08  3.49e-08  1.81e-07  8.08e-08  2.09e-07   erg/cm2
Peak flux       PL   1.68e+00  1.59e+00  1.05e+00  1.07e+00  4.75e+00  5.38e+00   ph/cm2/s
      90%_error_low -1.30e-01 -7.66e-02 -6.28e-02 -1.26e-01 -2.22e-01 -2.45e-01   ph/cm2/s
      90%_error_hi   1.34e-01  7.63e-02  6.25e-02  1.36e-01  2.22e-01  2.45e-01   ph/cm2/s
 
Fluence        CPL   2.33e-07  3.96e-07  4.61e-07  6.55e-07  1.35e-06  1.74e-06   erg/cm2
      90%_error_low -2.33e-08 -2.44e-08 -3.65e-08 -2.93e-07 -9.73e-08 -3.11e-07   erg/cm2
      90%_error_hi   2.36e-08  2.48e-08  3.64e-08  4.67e-07  9.75e-08  4.93e-07   erg/cm2
Peak flux      CPL   1.53e+00  1.66e+00  1.08e+00  6.26e-01  4.63e+00  4.90e+00   ph/cm2/s
      90%_error_low -1.59e-01 -8.91e-02 -6.96e-02 -1.77e-01 -2.34e-01 -3.06e-01   ph/cm2/s
      90%_error_hi   1.62e-01  9.03e-02  7.05e-02  2.58e-01  2.34e-01  3.47e-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
   45.7782    47.8444   0.0062    11.7746   -11.3354         2.5345158     30.764 TRIG_00761622                 
 
Foreground time interval of the image:
-31.624  15.165 (delta_t =  46.789 [sec])
Background time interval of the image:
-239.736 -31.624 (delta_t = 208.112 [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  -31.624 sec. to   15.368 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.74123     ( -0.0958005   0.0945525 )
Norm@50keV  : 3.22014E-03    ( -0.000177488   0.000176148 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.81 using 59 PHA bins.
# Reduced chi-squared =          1.049 for     57 degrees of freedom 
# Null hypothesis probability =   3.741059e-01
 
Photon flux (15-150 keV)    in 46.99 sec: 0.434038 ( -0.022115  0.022141 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.39716e-06 ( -8.00686e-08  8.08111e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from  -31.624 sec. to   15.368 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.45153     ( -0.331459   0.409521 )
Epeak [keV] : 86.9568      ( -27.5153 -86.96 )
Norm@50keV  : 4.60164E-03    ( -0.0014838   0.00295826 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.07 using 59 PHA bins.
# Reduced chi-squared =          1.037 for     56 degrees of freedom 
# Null hypothesis probability =   3.988830e-01
 
Photon flux (15-150 keV)    in 46.99 sec: 0.426725 ( -0.024008  0.023963 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.35358e-06 ( -9.72496e-08  9.75423e-08 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from    0.024 sec. to    1.024 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.60385     ( -0.0812116   0.0804759 )
Norm@50keV  : 3.69465E-02    ( -0.00174194   0.00173616 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.94 using 59 PHA bins.
# Reduced chi-squared =         0.8410 for     57 degrees of freedom 
# Null hypothesis probability =   7.981055e-01
 
Photon flux (15-150 keV)    in 1 sec: 4.75364 ( -0.22162  0.22188 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.45414e-07 ( -1.74471e-08  1.75387e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.024 sec. to    1.024 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.11032     ( -0.323267   0.348155 )
Epeak [keV] : 89.8663      ( -18.8944 72.5026 )
Norm@50keV  : 6.55137E-02    ( -0.0200511   0.0317385 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          40.88 using 59 PHA bins.
# Reduced chi-squared =         0.7300 for     56 degrees of freedom 
# Null hypothesis probability =   9.354556e-01
 
Photon flux (15-150 keV)    in 1 sec: 4.63325 ( -0.23428  0.23441 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.32767e-07 ( -1.93302e-08  1.93605e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 31.212 sec.
Hardness ratio (energy fluence ratio) = 1.19649276355

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

    S(15-50 keV)  = 6.27006e-07
S(50-150 keV) = 7.701662e-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 = 2.043826944350535E-01, IMY = 4.097110840777380E-02

    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:
-239.736000 -31.624000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 44.2471   5.5460    2.3  53.8    0.9   2.6232   5.0 ------	UNKNOWN                       
 61.0091  65.4388    2.7  11.1 -127.1   0.7553   4.3 ------	UNKNOWN                       
 94.4951  70.6024    2.3  24.3 -134.4   0.9355   5.1 ------	UNKNOWN                       
129.8537  54.6586    2.0  45.1 -120.2   4.6226   5.9 ------	UNKNOWN                       
130.4637  54.7799    2.9  45.2 -120.6   3.5288   4.7 ------	UNKNOWN

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

    Time interval of the image:
-31.624000 15.164600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 45.7782  47.8444    0.4  11.8  -11.3   2.5345  30.8 ------	UNKNOWN                       
201.1590  83.5246    2.1  36.9 -171.3   0.6173   5.6 ------	UNKNOWN                       
 97.5774  70.5790    2.5  25.3 -134.4   0.4205   4.6 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
47.564600 962.337800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6246  22.0166    0.5  39.7  -64.9  37.3057  23.8    0.5	Crab                          
 34.9225  40.9793    2.4  10.3   50.4   2.4637   4.8 ------	UNKNOWN                       
221.9694  75.1921    3.1  56.9  179.2  13.8393   3.8 ------	UNKNOWN                       
 48.3945  26.2094    3.1  21.7   -8.4   2.0603   3.8 ------	UNKNOWN                       
 70.9823   1.6539    2.3  51.1  -35.2   8.3210   4.9 ------	UNKNOWN