Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Fri Oct 19 18:38:35 EDT 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger853882
======================================================================

  Trigger: 00853882      Segment: 000

  BAT Trigger Time: 556288240   [s; MET]
      Trigger Stop: 556288368   [s; MET]
               UTC: 2018-08-18T12:30:18.552260    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 104.235169748593   Dec: 39.328619125846  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    10.17
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    10.17

  Analysis Position:   [ source = BAT ]
    RA: 104.235169748593   Dec: 39.328619125846  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 104.2255323748   Dec: 39.3103621957179  [deg; J2000]  
        { 06h 56m 54.1s , +39d 18' 37.3" }
         +/- 1.65256145493132 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.687718571376997 [arcmin] (formal 1-sigma fit error)
    SNR: 14.8410503592937
 
  Angular difference between the analysis and refined position is 1.183238 arcmin
 
  Partial Coding Fraction: 0.890625    [ including projection effects ]

  Duration
     T90: 137.459999918938 +/- 9.7000667230781
        Measured from: -89.7120000123978
                   to: 47.7479999065399     [s; relative to TRIGTIME]
     T50: 110.439999938011 +/- 4.47276741178899
        Measured from: -80.9279999732971
                   to: 29.5119999647141     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -82.1119999885559     
                   to: -81.1119999885559     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -93.5800000429153     
                   to: 62.7439999580383     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.225750   1.678227   0.883426   0.149702
           0.087604   0.090779   0.078307   0.068087 [error]
 Peak      0.043025   0.066838   0.023112   0.017085
           0.007485   0.008200   0.006842   0.005706 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  156.324  -93.580   62.744
T90   137.460  -89.712   47.748
T50   110.440  -80.928   29.512
Peak    1.000  -82.112  -81.112
 
 
====== 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      -1.772    -0.121      0.119       -           -               -         1.60e-03     -1.20e-04          1.19e-04      49.260   57
CPL     -1.044    -0.519      0.598       59.130     -10.649        37.451      4.00e-03     -1.89e-03          4.45e-03      43.260   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      -1.732     -0.295     0.285       -           -               -         8.62e-03     -1.62e-03          1.57e-03      64.110   57
CPL     -1.736      1.736     1.013     9998.880      N/A           N/A         8.60e-03        N/A               N/A         64.110   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   4.13e-07  6.43e-07  7.54e-07  1.71e-06  2.31e-06  3.52e-06   erg/cm2
      90%_error_low -4.27e-08 -4.34e-08 -7.56e-08 -3.27e-07 -1.77e-07 -4.03e-07   erg/cm2
      90%_error_hi   4.38e-08  4.34e-08  7.59e-08  3.75e-07  1.79e-07  4.40e-07   erg/cm2
Peak flux       PL   4.44e-01  3.89e-01  2.34e-01  2.13e-01  1.16e+00  1.28e+00   ph/cm2/s
      90%_error_low -1.07e-01 -6.35e-02 -5.64e-02 -8.54e-02 -1.88e-01 -2.12e-01   ph/cm2/s
      90%_error_hi   1.11e-01  6.34e-02  5.67e-02  1.16e-01  1.88e-01  2.13e-01   ph/cm2/s
 
Fluence        CPL   3.78e-07  6.98e-07  7.54e-07  5.76e-07  2.16e-06  2.41e-06   erg/cm2
      90%_error_low -4.97e-08 -5.77e-08 -8.62e-08 -2.91e-07 -2.03e-07 -3.57e-07   erg/cm2
      90%_error_hi   5.02e-08  5.95e-08  8.42e-08  6.25e-07  2.07e-07  6.43e-07   erg/cm2
Peak flux      CPL   4.45e-01  3.86e-01  2.33e-01  2.15e-01  1.16e+00  1.28e+00   ph/cm2/s
      90%_error_low -1.12e-01 -5.99e-02 -5.55e-02 -1.18e-01 -1.89e-01 -2.63e-01   ph/cm2/s
      90%_error_hi   1.13e-01  1.09e-01  5.73e-02  1.13e-01  1.88e-01  2.10e-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
  104.2255    39.3104   0.0129    29.4210    -8.7127         2.8004309     14.841 TRIG_00853882                 
 
Foreground time interval of the image:
-77.099  62.744 (delta_t = 139.843 [sec])
Background time interval of the image:




    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  -93.580 sec. to   62.744 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.77161     ( -0.121149   0.118759 )
Norm@50keV  : 1.60322E-03    ( -0.000119899   0.000118771 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.26 using 59 PHA bins.
# Reduced chi-squared =         0.8642 for     57 degrees of freedom 
# Null hypothesis probability =   7.572781e-01
 
Photon flux (15-150 keV)    in 156.3 sec: 0.218547 ( -0.014892  0.014905 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.30999e-06 ( -1.76999e-07  1.78748e-07 ) ergs/cm2
    Cutoff power-law model
    Time interval is from  -93.580 sec. to   62.744 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.04361     ( -0.519354   0.598274 )
Epeak [keV] : 59.1297      ( -10.6492 37.4506 )
Norm@50keV  : 4.00174E-03    ( -0.00188928   0.00444593 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.26 using 59 PHA bins.
# Reduced chi-squared =         0.7724 for     56 degrees of freedom 
# Null hypothesis probability =   8.935343e-01
 
Photon flux (15-150 keV)    in 156.3 sec: 0.211574 ( -0.015679  0.015669 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.1576e-06 ( -2.02946e-07  2.06683e-07 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from  -82.112 sec. to  -81.112 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.73154     ( -0.294612   0.284623 )
Norm@50keV  : 8.62467E-03    ( -0.00162044   0.00157474 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.11 using 59 PHA bins.
# Reduced chi-squared =          1.125 for     57 degrees of freedom 
# Null hypothesis probability =   2.413325e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.15842 ( -0.188337  0.18838 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.96856e-08 ( -1.52835e-08  1.56533e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from  -82.112 sec. to  -81.112 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.00705     ( 2.00705   1.2838 )
Epeak [keV] : 2.99380      (   )
Norm@50keV  : 6.02231E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.01 using 59 PHA bins.
# Reduced chi-squared =          1.143 for     56 degrees of freedom 
# Null hypothesis probability =   2.159988e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.15906 ( -0.18907  0.18803 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.00958e-08 ( -1.94864e-08  1.12776e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 137.46 sec.
Hardness ratio (energy fluence ratio) = 1.17154765157

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

    S(15-50 keV)  = 1.0565788e-06
S(50-150 keV) = 1.2534011e-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 = 5.574473002885124E-01, IMY = 8.542741209734461E-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:

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

    Time interval of the image:
-77.099400 62.744000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6046  22.0135    1.0  53.4    0.3   5.4893  11.5    1.6	Crab                          
259.0004  66.7174    2.7  46.0  139.2   2.7336   4.2 ------	UNKNOWN                       
104.2255  39.3103    0.8  29.4   -8.7   2.8001  14.8 ------	UNKNOWN                       
 88.9502  21.4470    2.2  51.5   -5.5   2.1671   5.3 ------	UNKNOWN                       
190.1023  23.0934    2.3  51.8 -137.1   4.6773   5.0 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
192.900600 963.088400
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6207  22.0174    0.3  24.7   29.5  31.5076  44.9    0.7	Crab                          
 58.4701  37.0031    2.8  35.7   79.2   6.2993   4.1 ------	UNKNOWN                       
 86.9088 -15.2887    2.7  56.9   -1.9  11.9748   4.3 ------	UNKNOWN                       
203.1833  67.6172    2.7  57.3 -175.4  15.9752   4.2 ------	UNKNOWN                       
125.2390  48.6750    2.8  17.7 -150.8   2.6951   4.1 ------	UNKNOWN                       
 91.9843 -14.6474    2.6  55.2   -7.5   8.5101   4.5 ------	UNKNOWN                       
186.9567  55.1449    3.0  54.8 -158.1  12.7864   3.8 ------	UNKNOWN                       
156.2611  41.7389    3.5  39.0 -132.9   4.1794   3.3 ------	UNKNOWN