Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Mon Jan 13 01:37:44 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger531003
======================================================================

  Trigger: 00531003      Segment: 000

  BAT Trigger Time: 366689648.32   [s; MET]
      Trigger Stop: 366689649.344   [s; MET]
               UTC: 2012-08-15T02:13:58.781640    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 273.955183891862   Dec: -52.1341064210625  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.23
     Image Trigger?:     NO
     Rate S/N Ratio:     16.0312195418814  [ if not an image trigger ]
     Image S/N Ratio:    9.23

  Analysis Position:   [ source = BAT ]
    RA: 273.955183891862   Dec: -52.1341064210625  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 273.97646673786   Dec: -52.1243089172957  [deg; J2000]  
        { 18h 15m 54.4s , -52d 07' 27.5" }
         +/- 1.79104064271745 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.729000159722781 [arcmin] (formal 1-sigma fit error)
    SNR: 13.2293704705461
 
  Angular difference between the analysis and refined position is 0.979839 arcmin
 
  Partial Coding Fraction: 0.2851562    [ including projection effects ]

  Duration
     T90: 7.23199999332428 +/- 2.51676054269014
        Measured from: -0.00800001621246338
                   to: 7.22399997711182     [s; relative to TRIGTIME]
     T50: 4.29999995231628 +/- 1.54716770236409
        Measured from: 0.804000020027161
                   to: 5.10399997234344     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.171999990940094     
                   to: 1.17199999094009     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.244000017642975     
                   to: 11.9679999947548     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.364728   0.370263   0.134919   0.037699
           0.036766   0.037678   0.031765   0.026992 [error]
 Peak      0.090140   0.083915   0.053956   0.013105
           0.011840   0.011975   0.009949   0.008615 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   12.212   -0.244   11.968
T90     7.232   -0.008    7.224
T50     4.300    0.804    5.104
Peak    1.000    0.172    1.172
 
 
====== 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      -2.300    -0.237      0.219       -           -               -         4.21e-03     -7.11e-04          6.97e-04      53.810   57
CPL     -1.184    -0.791      1.384       27.252      N/A           N/A         2.07e-02        N/A               N/A         50.290   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      -1.933     -0.253     0.241       -           -               -         1.53e-02     -2.56e-03          2.50e-03      61.720   57
CPL     -1.194     -0.891     1.309       46.081      N/A           N/A         4.08e-02        N/A               N/A         60.190   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   1.40e-07  1.59e-07  1.29e-07  1.75e-07  4.92e-07  6.03e-07   erg/cm2
      90%_error_low -2.11e-08 -1.97e-08 -2.86e-08 -6.43e-08 -6.82e-08 -1.07e-07   erg/cm2
      90%_error_hi   2.15e-08  1.95e-08  2.98e-08  8.52e-08  6.98e-08  1.21e-07   erg/cm2
Peak flux       PL   9.56e-01  7.45e-01  3.90e-01  2.96e-01  2.23e+00  2.39e+00   ph/cm2/s
      90%_error_low -1.97e-01 -1.07e-01 -8.27e-02 -1.05e-01 -3.23e-01 -3.42e-01   ph/cm2/s
      90%_error_hi   2.05e-01  1.07e-01  8.32e-02  1.34e-01  3.24e-01  3.42e-01   ph/cm2/s
 
Fluence        CPL    N/A      N/A      N/A      N/A      N/A      N/A      erg/cm2
      90%_error_low -2.11e-08 -1.97e-08 -2.86e-08 -6.43e-08 -6.82e-08 -1.07e-07   erg/cm2
      90%_error_hi   2.15e-08  1.95e-08  2.98e-08  8.52e-08  6.98e-08  1.21e-07   erg/cm2
Peak flux      CPL   8.93e-01  8.16e-01  3.90e-01  1.17e-01  2.18e+00  2.22e+00   ph/cm2/s
      90%_error_low -2.20e-01 -1.44e-01 -1.02e-01 -1.17e-01 -3.29e-01 -3.48e-01   ph/cm2/s
      90%_error_hi   2.24e-01  1.52e-01  9.39e-02  2.25e-01  3.29e-01  3.95e-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
  273.9765   -52.1243   0.0146    43.7996    19.6862         0.9560139     13.229 TRIG_00531003                 
 
Foreground time interval of the image:
 -0.244  11.968 (delta_t =  12.212 [sec])
Background time interval of the image:
-239.320  -0.244 (delta_t = 239.076 [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   -0.244 sec. to   11.968 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.30031     ( -0.236915   0.218651 )
Norm@50keV  : 4.21300E-03    ( -0.000710565   0.000696567 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.81 using 59 PHA bins.
# Reduced chi-squared =         0.9440 for     57 degrees of freedom 
# Null hypothesis probability =   5.955690e-01
 
Photon flux (15-150 keV)    in 12.21 sec: 0.736468 ( -0.086466  0.086482 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.91706e-07 ( -6.8214e-08  6.97882e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -0.244 sec. to   11.968 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.18405     ( -0.791134   1.38404 )
Epeak [keV] : 27.2523      (   )
Norm@50keV  : 2.06925E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.29 using 59 PHA bins.
# Reduced chi-squared =         0.8981 for     56 degrees of freedom 
# Null hypothesis probability =   6.898097e-01
 
Photon flux (15-150 keV)    in 12.21 sec: 0.716067 ( -0.087949  0.088286 ) 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    0.172 sec. to    1.172 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.93336     ( -0.253409   0.240784 )
Norm@50keV  : 1.52874E-02    ( -0.00255767   0.00250011 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.72 using 59 PHA bins.
# Reduced chi-squared =          1.083 for     57 degrees of freedom 
# Null hypothesis probability =   3.112799e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.22579 ( -0.32341  0.32377 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.40647e-07 ( -2.26557e-08  2.29857e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.172 sec. to    1.172 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.19407     ( -0.890586   1.30852 )
Epeak [keV] : 46.0806      (   )
Norm@50keV  : 4.08434E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.19 using 59 PHA bins.
# Reduced chi-squared =          1.075 for     56 degrees of freedom 
# Null hypothesis probability =   3.265274e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.18369 ( -0.32899  0.32919 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 7.232 sec.
Hardness ratio (energy fluence ratio) = 0.81211979602

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

    S(15-50 keV)  = 2.988823e-07
S(50-150 keV) = 1.9283135e-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 = 9.029025794022019E-01, IMY = -3.230404159963384E-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:
-239.320000 -0.244000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.4218 -60.6537  124.6  46.0  -56.8  -0.0776  -0.1    3.6	Cen X-3                       
186.3053 -62.7157    5.9  44.8  -46.0   1.0665   2.0   10.2	GX 301-2                      
264.6080 -44.3913    6.5  53.4   16.1   1.4030   1.8    6.8	4U 1735-44                    
260.0368 -43.1046    2.8  55.7   12.8   4.0365   4.1 ------	UNKNOWN                       
273.2647 -59.8847    2.4  37.1   13.6   1.2210   4.9 ------	UNKNOWN                       
328.8991 -69.9008    3.1  14.3   36.7   0.5984   3.7 ------	UNKNOWN                       
 43.1326 -40.7110    2.6  34.8  179.8   0.9479   4.5 ------	UNKNOWN                       
101.8941 -49.3889    2.0  43.2 -113.2   4.5028   5.6 ------	UNKNOWN

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

    Time interval of the image:
-0.244000 11.968000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.5468 -60.7354    5.0  46.0  -56.7   0.3159   2.3    9.6	Cen X-3                       
186.2570 -62.7881   32.6  44.7  -46.0  -0.0296  -0.4   11.0	GX 301-2                      
264.5992 -44.3410    5.4  53.4   16.1  -0.3297  -2.1    9.0	4U 1735-44                    
273.9765 -52.1243    0.9  43.8   19.7   0.9562  13.2 ------	UNKNOWN                       
344.5032 -81.7927    2.4  11.1  -20.4   0.1471   4.9 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
523.080610 962.777700
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5753 -40.5405    1.9  28.1  174.3   2.1105   6.2    2.3	Vela X-1                      
170.4669 -60.6050    4.7  27.8  109.1  -1.0645  -2.4    4.6	Cen X-3                       
186.7557 -62.7909    8.8  31.9   95.2   0.7071   1.3    3.0	GX 301-2                      
208.4396  12.9207    3.4  58.9  -24.4   8.0946   3.4 ------	UNKNOWN