Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Wed May  6 17:20:05 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger331332
======================================================================

  Trigger: 00331332      Segment: 000

  BAT Trigger Time: 245377733.632   [s; MET]
      Trigger Stop: 245377737.728   [s; MET]
               UTC: 2008-10-11T00:28:50.466880    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 220.360725648565   Dec: 33.6074738964866  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.49
     Image Trigger?:     NO
     Rate S/N Ratio:     10.9087121146357  [ if not an image trigger ]
     Image S/N Ratio:    7.49

  Analysis Position:   [ source = BAT ]
    RA: 220.360725648565   Dec: 33.6074738964866  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 220.362510504791   Dec: 33.5613723471907  [deg; J2000]  
        { 14h 41m 27.0s , +33d 33' 40.9" }
         +/- 2.12885854413827 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.05054307268918 [arcmin] (formal 1-sigma fit error)
    SNR: 10.3356365748531
 
  Angular difference between the analysis and refined position is 2.767531 arcmin
 
  Partial Coding Fraction: 1.015625    [ including projection effects ]

  Duration
     T90: 17.0879999995232 +/- 2.81381732604774
        Measured from: 1.10400000214577
                   to: 18.1920000016689     [s; relative to TRIGTIME]
     T50: 7.93599998950958 +/- 5.78731302841808
        Measured from: 2.64000001549721
                   to: 10.5760000050068     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.08399999141693     
                   to: 2.08399999141693     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.84799998998642     
                   to: 19.0879999995232     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.095880   0.133727   0.091764   0.006508
           0.018658   0.019603   0.017656   0.016202 [error]
 Peak      0.012157   0.016679   0.019483   0.000511
           0.004454   0.004702   0.004189   0.003970 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   18.240    0.848   19.088
T90    17.088    1.104   18.192
T50     7.936    2.640   10.576
Peak    1.000    1.084    2.084
 
 
====== 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      -1.498    -0.299      0.292       -           -               -         1.19e-03     -2.10e-04          2.05e-04      70.450   57
CPL     -1.333    -1.421      1.220      186.075    -186.075      -186.075      1.46e-03     -4.80e-04          5.12e-03      70.510   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      -1.129     -0.466     0.482       -           -               -         3.28e-03     -8.60e-04          8.60e-04      59.180   57
CPL     -0.383     -1.664     2.901      119.691    -119.691      -119.691      7.22e-03     -7.22e-03          1.12e-01      58.740   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   2.76e-08  5.07e-08  7.19e-08  2.14e-07  2.05e-07  3.64e-07   erg/cm2
      90%_error_low -6.99e-09 -8.29e-09 -1.70e-08 -8.97e-08 -4.00e-08 -1.07e-07   erg/cm2
      90%_error_hi   7.34e-09  8.24e-09  1.70e-08  1.27e-07  4.12e-08  1.39e-07   erg/cm2
Peak flux       PL   9.48e-02  1.19e-01  1.09e-01  1.74e-01  3.82e-01  4.96e-01   ph/cm2/s
      90%_error_low -4.37e-02 -3.73e-02 -3.37e-02 -9.14e-02 -1.02e-01 -1.38e-01   ph/cm2/s
      90%_error_hi   5.15e-02  3.61e-02  3.29e-02  1.42e-01  1.02e-01  1.50e-01   ph/cm2/s
 
Fluence        CPL   2.75e-08  5.07e-08  7.19e-08  2.13e-07  2.05e-07  3.63e-07   erg/cm2
      90%_error_low -7.91e-09 -8.19e-09 -1.71e-08 -1.56e-07 -2.77e-08 -1.95e-07   erg/cm2
      90%_error_hi   6.58e-09  1.15e-08  1.74e-08  6.92e-08  3.34e-08  7.11e-08   erg/cm2
Peak flux      CPL   7.90e-02  1.24e-01  1.17e-01  8.69e-02  3.69e-01  4.07e-01   ph/cm2/s
      90%_error_low -5.51e-02 -4.13e-02 -3.88e-02 -8.69e-02 -1.09e-01 -1.41e-01   ph/cm2/s
      90%_error_hi   6.22e-02  4.28e-02  4.21e-02  1.21e-01  1.07e-01  1.79e-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
  220.3625    33.5614   0.0187     7.7433  -132.8796         0.3969034     10.336 TRIG_00331332                 
 
Foreground time interval of the image:
  0.848  19.088 (delta_t =  18.240 [sec])
Background time interval of the image:
-147.731   0.848 (delta_t = 148.579 [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    0.848 sec. to   19.088 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.49753     ( -0.299445   0.291676 )
Norm@50keV  : 1.18604E-03    ( -0.000209614   0.00020488 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          70.45 using 59 PHA bins.
# Reduced chi-squared =          1.236 for     57 degrees of freedom 
# Null hypothesis probability =   1.086410e-01
 
Photon flux (15-150 keV)    in 18.24 sec: 0.147970 ( -0.023808  0.023813 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.05331e-07 ( -3.99886e-08  4.11675e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.848 sec. to   19.088 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.47282     ( -1.41034   1.23067 )
Epeak [keV] : 986.132      ( -993.689 -993.689 )
Norm@50keV  : 1.22348E-03    ( -0.000244699   0.00535958 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          70.45 using 59 PHA bins.
# Reduced chi-squared =          1.258 for     56 degrees of freedom 
# Null hypothesis probability =   9.259950e-02
 
Photon flux (15-150 keV)    in 18.24 sec: 0.147943 ( -0.024928  0.023822 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.05266e-07 ( -2.7669e-08  3.34467e-08 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from    1.084 sec. to    2.084 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.1293     ( -0.465805   0.481891 )
Norm@50keV  : 3.28364E-03    ( -0.000860125   0.000860124 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.18 using 59 PHA bins.
# Reduced chi-squared =          1.038 for     57 degrees of freedom 
# Null hypothesis probability =   3.960246e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.382036 ( -0.101654  0.102002 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.40204e-08 ( -9.97843e-09  1.02415e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    1.084 sec. to    2.084 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.383304     ( -1.66411   2.90079 )
Epeak [keV] : 119.691      ( -119.692 -119.692 )
Norm@50keV  : 7.21849E-03    ( -0.00721852   0.112075 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.74 using 59 PHA bins.
# Reduced chi-squared =          1.049 for     56 degrees of freedom 
# Null hypothesis probability =   3.753234e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.368770 ( -0.108772  0.107437 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.2499e-08 ( -1.06108e-08  1.0942e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 17.088 sec.
Hardness ratio (energy fluence ratio) = 1.4166745698

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

    S(15-50 keV)  = 7.827804e-08
S(50-150 keV) = 1.2705716e-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 = -9.252584379668545E-02, IMY = 9.964078974462079E-02

    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:
-147.731400 0.848000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5372  35.4109    7.6  30.8  163.8  -0.2252  -1.5    5.7	Her X-1                       
267.6986  31.1746    2.1  42.5  162.7   1.2569   5.4 ------	UNKNOWN                       
260.7128   4.6594    2.8  53.9 -163.6   1.4910   4.1 ------	UNKNOWN                       
216.1872  10.4138    2.4  29.9 -103.7   0.8248   4.8 ------	UNKNOWN

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

    Time interval of the image:
0.848000 19.088000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3447  35.4701   12.2  30.6  163.8  -0.0467  -1.0    9.4	Her X-1                       
255.8568  40.7120    2.4  30.2  153.2   0.2500   4.9 ------	UNKNOWN                       
145.2535  30.1438    2.2  56.9    0.7   1.2571   5.3 ------	UNKNOWN                       
255.0211  20.1441    2.4  39.1 -173.5   0.2732   4.9 ------	UNKNOWN                       
220.3625  33.5614    1.1   7.7 -132.9   0.3970  10.3 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
76.268590 962.419800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9754 -15.6348    0.6  54.6 -152.7  36.0096  18.2    0.4	Sco X-1                       
254.6867  35.3171    0.0  28.2  133.6  -0.3380  -0.7   11.3	Her X-1                       
245.4124  62.1043    3.6  32.6   78.4   2.4160   3.2 ------	UNKNOWN                       
272.3667  10.6461    2.7  52.7  160.0   9.2078   4.2 ------	UNKNOWN                       
257.2819   1.6739    2.9  47.0 -178.3   3.0647   4.1 ------	UNKNOWN                       
169.1687  12.9542    3.0  50.7  -44.4   9.6967   3.8 ------	UNKNOWN