GRB130912A: 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: Sat Jan 11 23:15:45 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger570465
======================================================================

  Trigger: 00570465      Segment: 000

  BAT Trigger Time: 400667708.956   [s; MET]
      Trigger Stop: 400667709.02   [s; MET]
               UTC: 2013-09-12T08:34:57.933280    [includes UTCF correction] 
       Where From?: (*SHORT BURST*) TDRSS scaled map message

  BAT 
    RA: 47.6148478284115   Dec: 13.9744257814072  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.18
     Image Trigger?:     NO
     Rate S/N Ratio:     46.2385120867876  [ if not an image trigger ]
     Image S/N Ratio:    7.18

  Analysis Position:   [ source = BAT ]
    RA: 47.6148478284115   Dec: 13.9744257814072  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 47.606543942408   Dec: 13.9984281667244  [deg; J2000]  
        { 03h 10m 25.6s , +13d 59' 54.3" }
         +/- 1.64734215996842 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.534050308930498 [arcmin] (formal 1-sigma fit error)
    SNR: 14.9082689189064
 
  Angular difference between the analysis and refined position is 1.519127 arcmin
 
  Partial Coding Fraction: 0.3125    [ including projection effects ]

  Duration
     T90: 0.283999919891357 +/- 0.0288444686585799
        Measured from: 0.0160000324249268
                   to: 0.299999952316284     [s; relative to TRIGTIME]
     T50: 0.20799994468689 +/- 0.0268327901402435
        Measured from: 0.0400000214576721
                   to: 0.247999966144562     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.335999965667725     
                   to: 0.664000034332275     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.00400000810623169     
                   to: 0.320000052452087     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.050283   0.077143   0.076630   0.033084
           0.006979   0.008371   0.009053   0.007701 [error]
 Peak      0.053123   0.088663   0.076403   0.033673
           0.011160   0.011890   0.011969   0.010707 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.316    0.004    0.320
T90     0.284    0.016    0.300
T50     0.208    0.040    0.248
Peak    1.000   -0.336    0.664
 
 
====== 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      -1.205    -0.195      0.195       -           -               -         5.46e-02     -5.98e-03          5.98e-03      46.510   57
CPL     -1.156    -0.243      0.564      965.147    -965.147      -965.147      5.75e-02        N/A               N/A         46.600   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      -1.268     -0.256     0.258       -           -               -         1.82e-02     -2.64e-03          2.64e-03      68.040   57
CPL     -1.078     -1.006    -0.891      272.455      N/A           N/A         2.22e-02        N/A               N/A         67.900   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   1.67e-08  3.68e-08  6.39e-08  2.58e-07  1.75e-07  3.75e-07   erg/cm2
      90%_error_low -3.36e-09 -4.59e-09 -8.62e-09 -7.01e-08 -2.16e-08 -7.65e-08   erg/cm2
      90%_error_hi   3.58e-09  4.52e-09  8.48e-09  8.54e-08  2.17e-08  8.96e-08   erg/cm2
Peak flux       PL   5.98e-01  6.91e-01  5.74e-01  8.02e-01  2.15e+00  2.67e+00   ph/cm2/s
      90%_error_low -1.62e-01 -1.20e-01 -9.76e-02 -2.56e-01 -3.27e-01 -3.99e-01   ph/cm2/s
      90%_error_hi   1.77e-01  1.18e-01  9.59e-02  3.21e-01  3.29e-01  4.04e-01   ph/cm2/s
 
Fluence        CPL   1.67e-08  3.67e-08  6.31e-08  2.67e-07  1.75e-07  3.76e-07   erg/cm2
      90%_error_low    N/A       N/A    -1.03e-08    N/A    -2.29e-08 -1.43e-07   erg/cm2
      90%_error_hi     N/A       N/A     1.29e-08    N/A     2.24e-08  4.13e-08   erg/cm2
Peak flux      CPL   5.71e-01  7.00e-01  5.88e-01  6.61e-01  2.14e+00  2.52e+00   ph/cm2/s
      90%_error_low -1.97e-01 -1.26e-01 -1.08e-01 -3.87e-01 -3.36e-01 -5.45e-01   ph/cm2/s
      90%_error_hi   1.74e-01  1.30e-01  1.17e-01  2.62e-01  3.37e-01  5.18e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   47.6065    13.9984   0.0129    47.6792   -21.9723         0.2522194     14.908 TRIG_00570465                 
 
Foreground time interval of the image:
  0.004   0.320 (delta_t =   0.316 [sec])
Background time interval of the image:
-239.956   0.004 (delta_t = 239.960 [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    0.004 sec. to    0.320 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.20452     ( -0.195473   0.19507 )
Norm@50keV  : 5.45680E-02    ( -0.00597822   0.00597635 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.51 using 59 PHA bins.
# Reduced chi-squared =         0.8160 for     57 degrees of freedom 
# Null hypothesis probability =   8.380601e-01
 
Photon flux (15-150 keV)    in 0.316 sec: 6.40929 ( -0.71795  0.71915 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.74738e-07 ( -2.15773e-08  2.17008e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.004 sec. to    0.320 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.20007     ( -0.243279   0.564312 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 5.48305E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.52 using 59 PHA bins.
# Reduced chi-squared =         0.8307 for     56 degrees of freedom 
# Null hypothesis probability =   8.127764e-01
 
Photon flux (15-150 keV)    in 0.316 sec: 6.43685 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.74992e-07 ( -2.28538e-08  2.23901e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   -0.336 sec. to    0.664 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.26773     ( -0.256151   0.258017 )
Norm@50keV  : 1.81503E-02    ( -0.00264424   0.00264421 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.04 using 59 PHA bins.
# Reduced chi-squared =          1.194 for     57 degrees of freedom 
# Null hypothesis probability =   1.503185e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.15305 ( -0.32715  0.32892 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.80834e-07 ( -2.86742e-08  2.88668e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.336 sec. to    0.664 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.07477     ( -0.00834442   0.10594 )
Epeak [keV] : 27.8869      (   )
Norm@50keV  : 4.21643E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.88 using 59 PHA bins.
# Reduced chi-squared =          1.194 for     56 degrees of freedom 
# Null hypothesis probability =   1.514097e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.13552 ( -0.33622  0.33701 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.79382e-07 ( -2.98135e-08  2.95572e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 0.2839999 sec.
Hardness ratio (energy fluence ratio) = 1.73568121771

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

S(15-50 keV)  = 5.350581e-08
S(50-150 keV) = 1.2123416e-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 = 1.018415789227998E+00, IMY = 4.108947869760430E-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:
-239.956000 0.004000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5537  35.2740    8.0  49.5  173.1   0.6405   1.4    4.7	Cyg X-1                       
308.1330  40.9129    1.7  42.2  179.9   2.0246   6.9    2.6	Cyg X-3                       
326.2038  38.1812    2.5  28.1  176.9   0.8727   4.5    8.6	Cyg X-2                       
324.6058  18.1346    2.3  33.0  137.8   1.4011   5.0 ------	UNKNOWN                       
 54.7380  36.1769    4.2  47.0  -53.5   2.4558   2.8 ------	UNKNOWN                       

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

Time interval of the image:
0.004000 0.320000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.7066  35.1434   15.2  49.4  172.9  -0.0131  -0.8    6.7	Cyg X-1                       
307.9171  40.9037  102.2  42.4  179.9  -0.0013  -0.1    9.2	Cyg X-3                       
326.1715  38.3225  495.9  28.2  177.1   0.0002   0.0    0.1	Cyg X-2                       
300.0769  21.6199    2.3  52.9  156.0   0.1681   5.1 ------	UNKNOWN                       
 47.6066  13.9984    0.8  47.7  -22.0   0.2522  14.9 ------	UNKNOWN                       
 29.4651  47.7826    2.4  30.0  -76.3   0.0565   4.9 ------	UNKNOWN                       
 39.4607  37.6698    2.3  34.7  -54.6   0.0548   5.0 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
77.344590 962.164300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6277  22.0012    0.4  35.1  -94.9  36.4178  32.5    0.9	Crab                          
 29.1837 -15.7740    3.8  34.9   45.7   2.4438   3.0 ------	UNKNOWN                       
 42.0512   1.4076    2.4  13.7   37.7   2.1599   4.7 ------	UNKNOWN                       
 56.8687 -40.6469    2.7  55.3    5.0   9.1436   4.3 ------	UNKNOWN                       
 71.1525 -32.3299    2.8  51.5  -12.0   4.3838   4.2 ------	UNKNOWN                       
 72.6838 -38.1858    2.9  57.2   -9.8   8.0378   4.0 ------	UNKNOWN                       
 87.9906 -27.1115    3.3  56.8  -30.0  10.0322   3.5 ------	UNKNOWN