Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Wed Jan 22 11:22:59 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger251634
======================================================================

  Trigger: 00251634      Segment: 000

  BAT Trigger Time: 188019609.856   [s; MET]
      Trigger Stop: 188019610.112   [s; MET]
               UTC: 2006-12-17T03:40:08.217280    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 160.441664347489   Dec: -21.1182033163857  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.27
     Image Trigger?:     NO
     Rate S/N Ratio:     21.6333076527839  [ if not an image trigger ]
     Image S/N Ratio:    8.27

  Analysis Position:   [ source = BAT ]
    RA: 160.441664347489   Dec: -21.1182033163857  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 160.401772484407   Dec: -21.1472640052747  [deg; J2000]  
        { 10h 41m 36.4s , -21d 08' 50.2" }
         +/- 2.27439398045063 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.07858092435411 [arcmin] (formal 1-sigma fit error)
    SNR: 9.40394847777584
 
  Angular difference between the analysis and refined position is 2.832760 arcmin
 
  Partial Coding Fraction: 0.8515625    [ including projection effects ]

  Duration
     T90: 0.224000006914139 +/- 0.0432666368624544
        Measured from: 0.0480000078678131
                   to: 0.272000014781952     [s; relative to TRIGTIME]
     T50: 0.104000002145767 +/- 0.0432665955340684
        Measured from: 0.111999988555908
                   to: 0.215999990701675     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.342000007629395     
                   to: 0.657999992370605     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.0279999971389771     
                   to: 0.283999979496002     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.006580   0.015815   0.022916   0.011837
           0.002696   0.003020   0.003106   0.002448 [error]
 Peak      0.007362   0.032125   0.023781   0.009740
           0.004981   0.005295   0.004949   0.004041 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.256    0.028    0.284
T90     0.224    0.048    0.272
T50     0.104    0.112    0.216
Peak    1.000   -0.342    0.658
 
 
====== 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      -0.663    -0.305      0.336       -           -               -         1.34e-02     -2.47e-03          2.38e-03      52.270   57
CPL     -0.585    -0.385      0.905      998.440    -998.440      -998.440      1.46e-02     -3.57e-03          -1.46e-02      52.430   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
 
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      -1.089     -0.351     0.369       -           -               -         4.62e-03     -1.00e-03          1.00e-03      73.420   57
CPL     -0.266     -0.998     1.907      109.846      N/A           N/A         1.17e-02        N/A               N/A         72.410   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   2.02e-09  6.23e-09  1.57e-08  1.13e-07  4.27e-08  1.37e-07   erg/cm2
      90%_error_low -7.49e-10 -1.49e-09 -2.67e-09 -4.06e-08 -7.46e-09 -4.20e-08   erg/cm2
      90%_error_hi   8.66e-10  1.44e-09  2.64e-09  5.72e-08  7.49e-09  5.71e-08   erg/cm2
Peak flux       PL   1.28e-01  1.65e-01  1.55e-01  2.57e-01  5.35e-01  7.06e-01   ph/cm2/s
      90%_error_low -4.92e-02 -4.29e-02 -3.76e-02 -1.09e-01 -1.18e-01 -1.62e-01   ph/cm2/s
      90%_error_hi   5.56e-02  4.19e-02  3.71e-02  1.51e-01  1.19e-01  1.70e-01   ph/cm2/s
 
Fluence        CPL   2.02e-09  6.22e-09  1.53e-08  1.13e-07  4.30e-08  1.35e-07   erg/cm2
      90%_error_low    N/A    -1.63e-09    N/A    -7.43e-08    N/A    -7.08e-08   erg/cm2
      90%_error_hi     N/A     1.59e-09    N/A     2.46e-08    N/A     2.51e-08   erg/cm2
Peak flux      CPL   1.10e-01  1.78e-01  1.68e-01  1.12e-01  5.21e-01  5.67e-01   ph/cm2/s
      90%_error_low -5.62e-02 -4.92e-02 -4.36e-02 -1.12e-01 -1.21e-01 -1.54e-01   ph/cm2/s
      90%_error_hi   6.35e-02  5.23e-02  4.60e-02  2.01e-01  1.21e-01  2.36e-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
  160.4018   -21.1473   0.0203    14.8813   -93.7177         0.0536185      9.404 TRIG_00251634                 
 
Foreground time interval of the image:
  0.028   0.284 (delta_t =   0.256 [sec])
Background time interval of the image:
-191.355   0.028 (delta_t = 191.383 [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    0.028 sec. to    0.284 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.663285     ( -0.305464   0.335935 )
Norm@50keV  : 1.34372E-02    ( -0.00247389   0.00238228 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.27 using 59 PHA bins.
# Reduced chi-squared =         0.9170 for     57 degrees of freedom 
# Null hypothesis probability =   6.527864e-01
 
Photon flux (15-150 keV)    in 0.256 sec: 1.55815 ( -0.26271  0.26362 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.27021e-08 ( -7.45608e-09  7.49171e-09 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.028 sec. to    0.284 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.655016     ( -0.385522   0.905086 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 1.35430E-02    ( -0.00248354   -0.0135439 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.28 using 59 PHA bins.
# Reduced chi-squared =         0.9337 for     56 degrees of freedom 
# Null hypothesis probability =   6.162927e-01
 
Photon flux (15-150 keV)    in 0.256 sec: 1.56577 ( -0.30199  0.28701 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.29921e-08 ( 0  0 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from   -0.342 sec. to    0.658 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.08893     ( -0.350768   0.369445 )
Norm@50keV  : 4.62007E-03    ( -0.00100124   0.00100004 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          73.42 using 59 PHA bins.
# Reduced chi-squared =          1.288 for     57 degrees of freedom 
# Null hypothesis probability =   7.049367e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.535340 ( -0.118138  0.118562 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.84808e-08 ( -1.14196e-08  1.15826e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -0.342 sec. to    0.658 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.266332     ( -0.997703   1.90702 )
Epeak [keV] : 109.846      (   )
Norm@50keV  : 1.16889E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          72.41 using 59 PHA bins.
# Reduced chi-squared =          1.293 for     56 degrees of freedom 
# Null hypothesis probability =   6.911319e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.521224 ( -0.120644  0.120979 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.57267e-08 ( -1.27019e-08  1.26286e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 0.224 sec.
Hardness ratio (energy fluence ratio) = 2.52574845991

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

    S(15-50 keV)  = 8.245975e-09
S(50-150 keV) = 3.445645e-08

    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 = -1.723001649683855E-02, IMY = 2.651703425182447E-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:
-191.355410 0.028000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.7599 -40.5694   13.4  29.1  -19.7  -0.1198  -0.9   10.6	Vela X-1                      
151.2876 -40.2557    2.9  27.3  -44.5   0.6249   3.9 ------	UNKNOWN

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

    Time interval of the image:
0.028000 0.284000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.3857 -40.6566    9.5  29.3  -19.2  -0.0069  -1.2    8.9	Vela X-1                      
109.5717   2.1599    2.0  40.4   71.9   0.1092   5.8 ------	UNKNOWN                       
162.7724  21.3568    2.1  37.8  166.3   0.0385   5.4 ------	UNKNOWN                       
106.7324 -41.3874    2.1  45.0    5.8   0.0535   5.6 ------	UNKNOWN                       
105.7201 -46.7104    2.3  48.2   -0.2   0.0566   5.0 ------	UNKNOWN                       
160.4017 -21.1473    1.2  14.9  -93.7   0.0536   9.4 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
48.444590 962.206400
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5536 -40.5557   50.0  28.7   14.9   0.0957   0.2    1.1	Vela X-1                      
170.1993 -60.4861    4.5  40.0  -34.3   1.7310   2.5    8.9	Cen X-3                       
186.6299 -62.7935    5.8  45.3  -43.3   2.7551   2.0    1.6	GX 301-2                      
162.8572  25.6704    3.3  46.8  156.2   3.6549   3.5 ------	UNKNOWN                       
200.7911  23.3716    3.3  59.4 -163.1  11.3683   3.5 ------	UNKNOWN