Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Fri Jan 17 16:47:06 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger431128
======================================================================

  Trigger: 00431128      Segment: 000

  BAT Trigger Time: 302865199.68   [s; MET]
      Trigger Stop: 302865200.704   [s; MET]
               UTC: 2010-08-07T09:13:13.622520    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 55.324189348915   Dec: 67.6787633437716  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.13
     Image Trigger?:     NO
     Rate S/N Ratio:     15.3297097167559  [ if not an image trigger ]
     Image S/N Ratio:    9.13

  Analysis Position:   [ source = BAT ]
    RA: 55.324189348915   Dec: 67.6787633437716  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 55.2995122773925   Dec: 67.6648710966458  [deg; J2000]  
        { 03h 41m 11.9s , +67d 39' 53.5" }
         +/- 1.80938584818832 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.773966194921213 [arcmin] (formal 1-sigma fit error)
    SNR: 13.0381712529179
 
  Angular difference between the analysis and refined position is 1.005581 arcmin
 
  Partial Coding Fraction: 0.3710938    [ including projection effects ]

  Duration
     T90: 7.74400001764297 +/- 1.43822114437232
        Measured from: -5.18400001525879
                   to: 2.56000000238419     [s; relative to TRIGTIME]
     T50: 2.75199997425079 +/- 1.11771195772738
        Measured from: -2.17599999904633
                   to: 0.575999975204468     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.340000033378601     
                   to: 0.659999966621399     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -6.0799999833107     
                   to: 3.13599997758865     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.274524   0.270979   0.093802   0.032216
           0.025555   0.026140   0.022505   0.019499 [error]
 Peak      0.060233   0.087174   0.058129   0.014330
           0.009229   0.009676   0.008161   0.006682 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    9.216   -6.080    3.136
T90     7.744   -5.184    2.560
T50     2.752   -2.176    0.576
Peak    1.000   -0.340    0.660
 
 
====== 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      -2.321    -0.243      0.224       -           -               -         3.80e-03     -6.49e-04          6.36e-04      49.100   57
CPL     -1.604    -0.411      1.677       20.015      N/A           N/A         1.07e-02        N/A               N/A         47.950   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      -1.627     -0.211     0.206       -           -               -         1.41e-02     -1.87e-03          1.85e-03      57.320   57
CPL     -0.865     -0.819     1.005       72.858     -20.108       -72.858      3.50e-02     -2.14e-02          7.84e-02      54.820   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   9.72e-08  1.09e-07  8.71e-08  1.16e-07  3.36e-07  4.09e-07   erg/cm2
      90%_error_low -1.39e-08 -1.31e-08 -1.97e-08 -4.36e-08 -4.58e-08 -7.21e-08   erg/cm2
      90%_error_hi   1.42e-08  1.29e-08  2.08e-08  5.89e-08  4.72e-08  8.34e-08   erg/cm2
Peak flux       PL   6.54e-01  6.11e-01  3.96e-01  3.96e-01  1.82e+00  2.06e+00   ph/cm2/s
      90%_error_low -1.29e-01 -8.02e-02 -6.57e-02 -1.16e-01 -2.34e-01 -2.61e-01   ph/cm2/s
      90%_error_hi   1.35e-01  7.97e-02  6.51e-02  1.40e-01  2.34e-01  2.62e-01   ph/cm2/s
 
Fluence        CPL    N/A      N/A      N/A      N/A      N/A      N/A      erg/cm2
      90%_error_low -1.39e-08 -1.31e-08 -1.97e-08 -4.36e-08 -4.58e-08 -7.21e-08   erg/cm2
      90%_error_hi   1.42e-08  1.29e-08  2.08e-08  5.89e-08  4.72e-08  8.34e-08   erg/cm2
Peak flux      CPL   5.80e-01  6.62e-01  4.21e-01  1.83e-01  1.78e+00  1.85e+00   ph/cm2/s
      90%_error_low -1.53e-01 -9.79e-02 -7.46e-02 -1.06e-01 -2.39e-01 -2.69e-01   ph/cm2/s
      90%_error_hi   1.57e-01  1.02e-01  7.67e-02  2.48e-01  2.39e-01  3.15e-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
   55.2995    67.6649   0.0148    32.9709  -110.1038         0.6500968     13.038 TRIG_00431128                 
 
Foreground time interval of the image:
 -6.080   3.136 (delta_t =   9.216 [sec])
Background time interval of the image:
-239.680  -6.080 (delta_t = 233.600 [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   -6.080 sec. to    3.136 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.32094     ( -0.243463   0.224106 )
Norm@50keV  : 3.79747E-03    ( -0.000648869   0.000636276 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.10 using 59 PHA bins.
# Reduced chi-squared =         0.8615 for     57 degrees of freedom 
# Null hypothesis probability =   7.622584e-01
 
Photon flux (15-150 keV)    in 9.216 sec: 0.671536 ( -0.074261  0.074261 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.35832e-07 ( -4.57756e-08  4.71801e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -6.080 sec. to    3.136 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.60404     ( -0.410979   1.67641 )
Epeak [keV] : 20.0153      (   )
Norm@50keV  : 1.07209E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.95 using 59 PHA bins.
# Reduced chi-squared =         0.8563 for     56 degrees of freedom 
# Null hypothesis probability =   7.692595e-01
 
Photon flux (15-150 keV)    in 9.216 sec: 0.670693 ( -0.073766  0.075477 ) 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   -0.340 sec. to    0.660 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.62671     ( -0.211092   0.205778 )
Norm@50keV  : 1.40772E-02    ( -0.00187235   0.00185385 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.32 using 59 PHA bins.
# Reduced chi-squared =          1.006 for     57 degrees of freedom 
# Null hypothesis probability =   4.631439e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.82434 ( -0.23394  0.23425 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.31262e-07 ( -1.83994e-08  1.85753e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -0.340 sec. to    0.660 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.86492     ( -0.818517   1.00529 )
Epeak [keV] : 72.8582      ( -20.1085 -72.8581 )
Norm@50keV  : 3.49781E-02    ( -0.0214037   0.0783594 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.82 using 59 PHA bins.
# Reduced chi-squared =         0.9790 for     56 degrees of freedom 
# Null hypothesis probability =   5.194040e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.78192 ( -0.23937  0.23919 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.25594e-07 ( -1.93878e-08  1.96205e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 7.744 sec.
Hardness ratio (energy fluence ratio) = 0.800571633875

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

    S(15-50 keV)  = 2.060455e-07
S(50-150 keV) = 1.2979197e-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 = -2.229676086232162E-01, IMY = 6.091630567530077E-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:
-239.680000 -6.080000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5777  35.1874    2.4  47.4  134.9   3.7875   4.9    1.1	Cyg X-1                       
308.1237  40.9250    2.6  38.7  136.7   1.8325   4.4    1.8	Cyg X-3                       
326.0509  38.3141    3.8  27.9  120.0   0.7734   3.0    5.7	Cyg X-2                       
 10.2984  10.2226    2.4  38.1   23.6   1.2393   4.8 ------	UNKNOWN

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

    Time interval of the image:
-6.080000 3.136000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5885  35.2000   10.8  47.4  134.9   0.1445   1.1    0.1	Cyg X-1                       
308.1020  40.9323   10.3  38.7  136.7  -0.0640  -1.1    1.3	Cyg X-3                       
326.3474  38.2922   13.9  27.8  119.7   0.0341   0.8    8.5	Cyg X-2                       
333.6237  46.7562    2.2  19.5  134.0   0.1638   5.3 ------	UNKNOWN                       
342.4993  58.2971    3.0  15.9  175.1   0.1060   3.8 ------	UNKNOWN                       
  2.7460  47.8787    1.9   0.2  -94.5   0.1709   5.9 ------	UNKNOWN                       
313.0377  68.5979    2.2  31.9 -175.5   0.1856   5.3 ------	UNKNOWN                       
 43.6996   4.5294    2.5  55.7  -16.5   0.5140   4.7 ------	UNKNOWN                       
 55.2995  67.6649    0.9  33.0 -110.1   0.6500  13.0 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
70.020600 962.353600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6370  22.0202    0.5  48.9  -36.6  33.7629  25.3    0.4	Crab                          
337.1348  56.4012    2.6  35.5  110.5   4.5130   4.4 ------	UNKNOWN                       
 96.3086  27.3740    3.6  47.2  -53.5   7.5974   3.3 ------	UNKNOWN