Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Wed Jan 22 16:04:14 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger211957
======================================================================

  Trigger: 00211957      Segment: 000

  BAT Trigger Time: 170353711.168   [s; MET]
      Trigger Stop: 170353711.68   [s; MET]
               UTC: 2006-05-26T16:28:29.950920    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 232.845565859311   Dec: 0.244218930890226  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.05
     Image Trigger?:     NO
     Rate S/N Ratio:     20.3469899493758  [ if not an image trigger ]
     Image S/N Ratio:    9.05

  Analysis Position:   [ source = BAT ]
    RA: 232.845565859311   Dec: 0.244218930890226  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 232.833766596179   Dec: 0.295772893378037  [deg; J2000]  
        { 15h 31m 20.1s , +00d 17' 44.8" }
         +/- 1.40856022592367 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.642721206825804 [arcmin] (formal 1-sigma fit error)
    SNR: 18.6458447751036
 
  Angular difference between the analysis and refined position is 3.173218 arcmin
 
  Partial Coding Fraction: 0.6171875    [ including projection effects ]

  Duration
     T90: 298.040000021458 +/- 22.8986889494558
        Measured from: 0.355999976396561
                   to: 298.395999997854     [s; relative to TRIGTIME]
     T50: 249.256000012159 +/- 8.11129977774405
        Measured from: 7.52399998903275
                   to: 256.780000001192     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.143999993801117     
                   to: 1.14399999380112     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.36000001430511     
                   to: 310.17199999094     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.004617   0.783562   0.634497   0.179950
           0.085851   0.083869   0.074418   0.067353 [error]
 Peak      0.042449   0.078881   0.070239   0.019653
           0.006582   0.007346   0.006651   0.005146 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  311.532   -1.360  310.172
T90   298.040    0.356  298.396
T50   249.256    7.524  256.780
Peak    1.000    0.144    1.144
 
 
====== 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      -1.961    -0.227      0.216       -           -               -         4.52e-04     -6.17e-05          5.93e-05      66.050   57
CPL     -1.968    -1.019     -0.060     9999.310    -9832.547      -9662.366      4.51e-04     -3.54e-04          -6.76e-05      66.060   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      -1.300     -0.169     0.169       -           -               -         1.40e-02     -1.43e-03          1.43e-03      70.110   57
CPL     -0.336     -0.758     0.928       89.792     -22.198       128.222      4.12e-02     -2.32e-02          7.23e-02      65.210   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   2.77e-07  3.85e-07  3.95e-07  7.42e-07  1.29e-06  1.80e-06   erg/cm2
      90%_error_low -4.28e-08 -3.89e-08 -7.53e-08 -2.54e-07 -1.64e-07 -3.36e-07   erg/cm2
      90%_error_hi   4.40e-08  3.88e-08  7.69e-08  3.35e-07  1.68e-07  4.00e-07   erg/cm2
Peak flux       PL   4.75e-01  5.38e-01  4.37e-01  5.92e-01  1.67e+00  2.04e+00   ph/cm2/s
      90%_error_low -8.34e-02 -6.11e-02 -5.35e-02 -1.36e-01 -1.73e-01 -2.17e-01   ph/cm2/s
      90%_error_hi   8.79e-02  6.05e-02  5.30e-02  1.59e-01  1.73e-01  2.19e-01   ph/cm2/s
 
Fluence        CPL   2.67e-07  3.59e-07  3.69e-07  8.34e-07  1.22e-06  1.82e-06   erg/cm2
      90%_error_low -4.62e-08 -6.27e-08 -6.30e-08 -7.82e-07 -2.11e-07 -2.98e-07   erg/cm2
      90%_error_hi   9.35e-08  5.50e-08  5.85e-08  3.23e-08  1.87e-07  2.79e-07   erg/cm2
Peak flux      CPL   3.90e-01  5.82e-01  4.76e-01  2.42e-01  1.61e+00  1.69e+00   ph/cm2/s
      90%_error_low -1.03e-01 -7.25e-02 -6.36e-02 -1.20e-01 -1.81e-01 -2.23e-01   ph/cm2/s
      90%_error_hi   1.08e-01  7.49e-02  6.52e-02  2.39e-01  1.80e-01  2.82e-01   ph/cm2/s
 
======================================================================




Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  232.8338     0.2958   0.0103    24.8540    52.1007         0.7632742     18.646 TRIG_00211957                 
 
Foreground time interval of the image:
 -1.360   9.933 (delta_t =  11.293 [sec])
Background time interval of the image:
-239.168  -1.360 (delta_t = 237.808 [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
Multiple GTIs in the spectrum
tstart tstop
-1.360000 79.842100
80.832000 310.172000
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.96077     ( -0.227342   0.215901 )
Norm@50keV  : 4.52427E-04    ( -6.1674e-05   5.92804e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.05 using 59 PHA bins.
# Reduced chi-squared =          1.159 for     57 degrees of freedom 
# Null hypothesis probability =   1.925837e-01
 
Photon flux (15-150 keV)    in 310.5 sec: 6.66732E-02 ( -0.0067141  0.0067176 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.29346e-06 ( -1.63682e-07  1.68255e-07 ) ergs/cm2
 
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-1.360000 79.842100
80.832000 310.172000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.69236     ( -0.294575   0.66403 )
Epeak [keV] : 227.833      ( -61.1713 109.01 )
Norm@50keV  : 2.03239E-04    ( -0.000105915   0.000180246 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.23 using 59 PHA bins.
# Reduced chi-squared =          1.111 for     56 degrees of freedom 
# Null hypothesis probability =   2.640266e-01
 
Photon flux (15-150 keV)    in 310.5 sec: 5.38966E-02 ( -0.0146018  0.0133595 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.22355e-06 ( -2.10778e-07  1.8727e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model
Time interval is from    0.144 sec. to    1.144 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.29997     ( -0.168911   0.168861 )
Norm@50keV  : 1.39663E-02    ( -0.00142914   0.00142761 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          70.11 using 59 PHA bins.
# Reduced chi-squared =          1.230 for     57 degrees of freedom 
# Null hypothesis probability =   1.139140e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.66623 ( -0.1725  0.17271 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.38029e-07 ( -1.56914e-08  1.58219e-08 ) ergs/cm2
 
Cutoff power-law model
Time interval is from    0.144 sec. to    1.144 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.336058     ( -0.757631   0.92838 )
Epeak [keV] : 89.7918      ( -22.1984 128.223 )
Norm@50keV  : 4.12090E-02    ( -0.0232476   0.0722748 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          65.21 using 59 PHA bins.
# Reduced chi-squared =          1.164 for     56 degrees of freedom 
# Null hypothesis probability =   1.871355e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.60531 ( -0.18076  0.17962 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.29876e-07 ( -1.72159e-08  1.72841e-08 ) ergs/cm2
 

Time-resolved spectra




Distribution

T90 vs. Hardness ratio plot

T90                                   = 298.04 sec.
Hardness ratio (energy fluence ratio) = 1.02758983459

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

S(15-50 keV)  = 6.617423e-07
S(50-150 keV) = 6.316997e-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 = 2.845381887767856E-01, IMY = -3.655144875083937E-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:
-239.168000 -1.360000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.2914  35.3213   84.8  51.8   -0.4   0.0563   0.1    8.2	Her X-1                       
166.0482 -30.8355    2.7  54.2  177.0   2.4392   4.2 ------	UNKNOWN                       
214.0225  55.7399    2.7  50.7  -44.5   3.4892   4.2 ------	UNKNOWN                       
206.6188  53.5641    3.0  48.4  -50.0   3.3319   3.9 ------	UNKNOWN                       

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

Time interval of the image:
-1.360000 9.932600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5850  35.2875    4.6  52.0   -0.2   0.2192   2.5    7.1	Her X-1                       
232.8338   0.2957    0.6  24.9   52.1   0.7633  18.6 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
59.332650 79.842100
80.832000 962.923200
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9741 -15.6363    0.2  19.9   78.6  31.0780  50.4    0.4	Sco X-1                       
254.6990  35.2475    0.0  40.5  -37.1   0.9651   1.1   13.1	Her X-1                       
262.9527 -24.7708    5.6  38.4   67.9   3.3680   2.1    3.4	GX 1+4                        
268.3854  -1.5452    2.5  35.6   28.0   3.5794   4.6    5.7	SW J1753.5-0127               
274.0269 -14.0600    3.0  43.2   46.1   5.6933   3.9    1.9	GX 17+2