GRB120913A: Summary Image Light curves Spectra Distribution Others

Analysis Summary

Notes:

• 1) No attempt has been made to eliminate the non-significant decimal places.
• 2) This batgrbproduct analysis is done using the HEASARC data.
• 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Mon Jan 13 00:45:41 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger533568
======================================================================

  Trigger: 00533568      Segment: 000

  BAT Trigger Time: 369260311.552   [s; MET]
      Trigger Stop: 369260312.576   [s; MET]
               UTC: 2012-09-13T20:18:21.905720    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 146.436815162705   Dec: 26.9767800186672  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.27
     Image Trigger?:     NO
     Rate S/N Ratio:     11.6189500386223  [ if not an image trigger ]
     Image S/N Ratio:    7.27

  Analysis Position:   [ source = BAT ]
    RA: 146.436815162705   Dec: 26.9767800186672  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 146.400411342535   Dec: 26.9594481491567  [deg; J2000]  
        { 09h 45m 36.1s , +26d 57' 34.0" }
         +/- 1.24454476276929 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.468287225517763 [arcmin] (formal 1-sigma fit error)
    SNR: 22.2530253902983
 
  Angular difference between the analysis and refined position is 2.207060 arcmin
 
  Partial Coding Fraction: 0.703125    [ including projection effects ]

  Duration
     T90: 36.0439999699593 +/- 5.67929154683683
        Measured from: 0.452000021934509
                   to: 36.4959999918938     [s; relative to TRIGTIME]
     T50: 5.55999994277954 +/- 13.4587072384618
        Measured from: 20.7800000309944
                   to: 26.339999973774     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 22.4560000300407     
                   to: 23.4560000300407     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.719999969005585     
                   to: 39.8000000119209     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.740776   0.648901   0.312983   0.037106
           0.039823   0.040672   0.036088   0.033217 [error]
 Peak      0.110015   0.097983   0.052952   0.009644
           0.007574   0.007711   0.006552   0.005483 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   40.520   -0.720   39.800
T90    36.044    0.452   36.496
T50     5.560   20.780   26.340
Peak    1.000   22.456   23.456
 
 
====== 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      -2.176    -0.151      0.144       -           -               -         2.32e-03     -2.28e-04          2.24e-04      58.460   57
CPL     -2.168    -0.210      0.137     9999.360      N/A           N/A         2.33e-03        N/A               N/A         58.480   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      -2.063     -0.170     0.162       -           -               -         1.47e-02     -1.65e-03          1.62e-03      50.450   57
CPL     -1.632     -0.485     0.702       34.991     -27.564       -34.991      2.63e-02        N/A               N/A         48.960   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   2.27e-07  2.77e-07  2.45e-07  3.74e-07  8.80e-07  1.12e-06   erg/cm2
      90%_error_low -2.27e-08 -2.00e-08 -3.31e-08 -9.10e-08 -7.44e-08 -1.31e-07   erg/cm2
      90%_error_hi   2.32e-08  2.00e-08  3.40e-08  1.10e-07  7.58e-08  1.45e-07   erg/cm2
Peak flux       PL   1.04e+00  7.53e-01  3.60e-01  2.43e-01  2.27e+00  2.40e+00   ph/cm2/s
      90%_error_low -1.26e-01 -6.43e-02 -5.32e-02 -6.24e-02 -1.94e-01 -2.05e-01   ph/cm2/s
      90%_error_hi   1.29e-01  6.43e-02  5.41e-02  7.49e-02  1.94e-01  2.05e-01   ph/cm2/s
 
Fluence        CPL   2.19e-07  2.90e-07  2.43e-07  3.94e-07  8.36e-07  1.12e-06   erg/cm2
      90%_error_low -2.54e-08 -3.67e-08 -3.09e-08 -7.14e-08 -8.76e-08 -1.25e-07   erg/cm2
      90%_error_hi   2.45e-08  2.64e-08  3.62e-08  1.68e-07  9.18e-08  1.98e-07   erg/cm2
Peak flux      CPL   1.00e+00  7.91e-01  3.55e-01  1.31e-01  2.23e+00  2.28e+00   ph/cm2/s
      90%_error_low -1.41e-01 -8.23e-02 -5.97e-02 -7.75e-02 -2.01e-01 -2.23e-01   ph/cm2/s
      90%_error_hi   1.41e-01  8.47e-02  5.80e-02  1.77e-01  2.01e-01  2.58e-01   ph/cm2/s
 
======================================================================

Image

Pre-slew 15.0-350.0 keV image (Event data)

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  146.4004    26.9594   0.0086    20.5599   -91.5906         1.5776889     22.253 TRIG_00533568                 
 
Foreground time interval of the image:
 -0.720  30.349 (delta_t =  31.069 [sec])
Background time interval of the image:
-239.552  -0.720 (delta_t = 238.832 [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

Other quick-look light curves:

• 64 ms binning (zoomed)
• 16 ms binning (zoomed)
• 8 ms binning (zoomed)
• 2 ms binning (zoomed)
• SN=5 or 10 s binning (full-time range)
• Raw light curve

Spectra

Notes:

• 1) The fitting includes the systematic errors.
• 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
• 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.

Time averaged spectrum fit using the average DRM

Power-law model

Time interval is from   -0.720 sec. to   39.800 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.17649     ( -0.150629   0.144302 )
Norm@50keV  : 2.31599E-03    ( -0.000227806   0.000224269 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.46 using 59 PHA bins.
# Reduced chi-squared =          1.026 for     57 degrees of freedom 
# Null hypothesis probability =   4.215796e-01
 
Photon flux (15-150 keV)    in 40.52 sec: 0.378780 ( -0.026878  0.026892 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.79689e-07 ( -7.43676e-08  7.58299e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.720 sec. to   39.800 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.16809     ( -0.209824   0.137026 )
Epeak [keV] : 9999.36      (   )
Norm@50keV  : 2.33273E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.47 using 59 PHA bins.
# Reduced chi-squared =          1.044 for     56 degrees of freedom 
# Null hypothesis probability =   3.846534e-01
 
Photon flux (15-150 keV)    in 40.52 sec: 0.370663 ( -0.028637  0.028667 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.3643e-07 ( -8.76411e-08  9.18082e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   22.456 sec. to   23.456 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.06327     ( -0.169664   0.162043 )
Norm@50keV  : 1.46977E-02    ( -0.00165462   0.00162352 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.45 using 59 PHA bins.
# Reduced chi-squared =         0.8851 for     57 degrees of freedom 
# Null hypothesis probability =   7.175318e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.27148 ( -0.19375  0.1938 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.36138e-07 ( -1.3913e-08  1.41935e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   22.456 sec. to   23.456 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.63182     ( -0.484664   0.702156 )
Epeak [keV] : 34.9907      ( -27.5638 -34.9907 )
Norm@50keV  : 2.62612E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          48.96 using 59 PHA bins.
# Reduced chi-squared =         0.8743 for     56 degrees of freedom 
# Null hypothesis probability =   7.361955e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.23257 ( -0.20076  0.20084 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 36.044 sec.
Hardness ratio (energy fluence ratio) = 0.88489124015

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

S(15-50 keV)  = 5.042826e-07
S(50-150 keV) = 3.754161e-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 = -1.041136773349213E-02, IMY = 3.749328755434775E-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:
-239.552000 -0.720000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6353  22.0121    0.7  37.4   65.0   8.2905  16.4    0.2	Crab                          
114.5000  -9.3847    2.9  44.7   -3.1   1.3759   4.0 ------	UNKNOWN                       
198.1061  48.1507    4.9  55.2 -145.1   3.6106   2.4 ------	UNKNOWN                       

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

Time interval of the image:
-0.720000 30.348610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6094  21.9098    7.0  37.5   64.9  -0.2493  -1.6    6.4	Crab                          
146.4004  26.9594    0.5  20.6  -91.6   1.5779  22.3 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
232.948600 809.648590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.5985 -60.6742    8.1  48.8 -166.7  -1.8134  -1.4    8.9	Cen X-3                       
186.6452 -62.7751    0.6  41.9 -171.8  14.8614  18.9    0.4	GX 301-2                      
244.9768 -15.6409    0.2  20.0    7.4  24.0158  53.1    0.2	Sco X-1                       
256.0306 -37.8676    3.5  17.8   88.1   1.7491   3.3    2.5	4U 1700-377                   
256.4225 -36.4012    1.3  18.0   83.2   4.5433   8.8    1.5	GX 349+2                      
262.8393 -24.8463   28.0  25.9   55.6  -0.2784  -0.4   11.0	GX 1+4                        
264.6263 -44.5744    7.1  25.6  102.2   1.1889   1.6    9.0	4U 1735-44                    
268.3772  -1.4365    3.6  44.9   29.2   3.5516   3.2    1.1	SW J1753.5-0127               
270.2806 -25.1628    8.7  31.9   62.0   1.1110   1.4    5.0	GX 5-1                        
270.3115 -25.6103    4.8  31.7   62.8   2.0518   2.4    8.0	GRS 1758-258                  
274.0613 -14.0064    5.5  40.5   48.5   2.5373   2.1    3.7	GX 17+2                       
275.9537 -30.4745    4.4  34.8   74.2   2.6277   2.6    6.6	H1820-303                     
262.9629 -33.7813    4.5  23.4   76.3   1.5239   2.6    3.5	GX 354-0                      
286.7209 -75.4694    2.3  48.6  142.2  11.1348   4.9 ------	UNKNOWN                       
255.0225 -19.3747    2.9  22.9   34.7   2.0362   4.0 ------	UNKNOWN                       
234.1556  10.1435    3.5  43.5  -23.4   2.8623   3.3 ------	UNKNOWN                       
233.0596  25.4829    3.9  58.9  -24.3  12.5102   2.9 ------	UNKNOWN