GRB081016B

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: Sun Jan 19 21:41:27 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger331856
======================================================================

  Trigger: 00331856      Segment: 000

  BAT Trigger Time: 245879237.696   [s; MET]
      Trigger Stop: 245879239.744   [s; MET]
               UTC: 2008-10-16T19:47:14.515960    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 14.6151239564649   Dec: -43.5430521619781  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.48
     Image Trigger?:     NO
     Rate S/N Ratio:     19.6977156035922  [ if not an image trigger ]
     Image S/N Ratio:    7.48

  Analysis Position:   [ source = BAT ]
    RA: 14.6151239564649   Dec: -43.5430521619781  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 14.5889026488615   Dec: -43.5373558434781  [deg; J2000]  
        { 00h 58m 21.3s , -43d 32' 14.5" }
         +/- 2.25186570369933 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.911745631391313 [arcmin] (formal 1-sigma fit error)
    SNR: 9.53863556340353
 
  Angular difference between the analysis and refined position is 1.190568 arcmin
 
  Partial Coding Fraction: 0.984375    [ including projection effects ]

  Duration
     T90: 2.61599999666214 +/- 0.792706748977127
        Measured from: 0.23199999332428
                   to: 2.84799998998642     [s; relative to TRIGTIME]
     T50: 1.17200002074242 +/- 0.311589493590561
        Measured from: 0.787999987602234
                   to: 1.96000000834465     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.503999978303909     
                   to: 1.50399997830391     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.0200000107288361     
                   to: 2.95600000023842     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.022154   0.044121   0.049977   0.030735
           0.007569   0.008158   0.007336   0.006451 [error]
 Peak      0.011400   0.016071   0.029818   0.016023
           0.004412   0.004821   0.004412   0.003918 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    2.976   -0.020    2.956
T90     2.616    0.232    2.848
T50     1.172    0.788    1.960
Peak    1.000    0.504    1.504
 
 
====== 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      -0.789    -0.304      0.334       -           -               -         3.10e-03     -5.55e-04          5.37e-04      44.500   57
CPL     -0.708    -0.385      1.068      959.360    -959.360      -959.360      3.36e-03     -7.94e-04          -3.36e-03      44.620   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      -0.527     -0.379     0.434       -           -               -         4.53e-03     -1.09e-03          1.01e-03      41.940   57
CPL     -0.421     -0.490     1.323      998.253    -998.253      -998.253      4.96e-03     -1.49e-03          -4.96e-03      42.120   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   6.08e-09  1.73e-08  4.01e-08  2.52e-07  1.08e-07  3.15e-07   erg/cm2
      90%_error_low -2.22e-09 -4.06e-09 -6.81e-09 -9.04e-08 -1.85e-08 -9.36e-08   erg/cm2
      90%_error_hi   2.56e-09  3.92e-09  6.73e-09  1.28e-07  1.86e-08  1.27e-07   erg/cm2
Peak flux       PL   7.41e-02  1.34e-01  1.86e-01  5.37e-01  5.34e-01  9.31e-01   ph/cm2/s
      90%_error_low -3.51e-02 -4.34e-02 -3.37e-02 -2.02e-01 -1.05e-01 -2.05e-01   ph/cm2/s
      90%_error_hi   4.51e-02  4.33e-02  3.36e-02  2.93e-01  1.06e-01  2.54e-01   ph/cm2/s
 
Fluence        CPL   6.07e-09  1.73e-08  3.93e-08  2.68e-07  1.09e-07  3.12e-07   erg/cm2
      90%_error_low    N/A       N/A    -8.70e-09 -1.93e-07 -1.95e-08 -1.73e-07   erg/cm2
      90%_error_hi     N/A       N/A     1.20e-08  4.07e-08  1.77e-08  5.56e-08   erg/cm2
Peak flux      CPL   7.40e-02  1.35e-01  1.86e-01  5.31e-01  5.42e-01  9.60e-01   ph/cm2/s
      90%_error_low     N/A       N/A       N/A       N/A       N/A   -3.98e-01   ph/cm2/s
      90%_error_hi      N/A       N/A       N/A       N/A       N/A    2.50e-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
   14.5889   -43.5374   0.0203    17.2807    13.0352         0.1537437      9.539 TRIG_00331856                 
 
Foreground time interval of the image:
 -0.020   2.956 (delta_t =   2.976 [sec])
Background time interval of the image:
-239.696  -0.020 (delta_t = 239.676 [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:

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   -0.020 sec. to    2.956 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.788878     ( -0.304357   0.333927 )
Norm@50keV  : 3.10088E-03    ( -0.000555197   0.000537287 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.50 using 59 PHA bins.
# Reduced chi-squared =         0.7808 for     57 degrees of freedom 
# Null hypothesis probability =   8.858992e-01
 
Photon flux (15-150 keV)    in 2.976 sec: 0.356536 ( -0.060619  0.061008 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.08359e-07 ( -1.85324e-08  1.86354e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.020 sec. to    2.956 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.781617     ( -0.382729   1.07028 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 3.12305E-03    ( -0.000556881   -0.0031232 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.51 using 59 PHA bins.
# Reduced chi-squared =         0.7949 for     56 degrees of freedom 
# Null hypothesis probability =   8.655589e-01
 
Photon flux (15-150 keV)    in 2.976 sec: 0.358239 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.0918e-07 ( -1.94612e-08  1.77059e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    0.504 sec. to    1.504 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.52736     ( -0.379199   0.434258 )
Norm@50keV  : 4.52933E-03    ( -0.00108671   0.00100731 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          41.94 using 59 PHA bins.
# Reduced chi-squared =         0.7357 for     57 degrees of freedom 
# Null hypothesis probability =   9.325174e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.534104 ( -0.105094  0.106327 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.00247e-08 ( -1.13907e-08  1.14184e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.504 sec. to    1.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.516865     ( -0.489563   1.32312 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 4.56582E-03    ( -0.00109102   -0.00456661 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          41.95 using 59 PHA bins.
# Reduced chi-squared =         0.7491 for     56 degrees of freedom 
# Null hypothesis probability =   9.182996e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.541876 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.00772e-08 ( -1.47854e-08  1.47036e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 2.616 sec.
Hardness ratio (energy fluence ratio) = 2.31520693363

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

S(15-50 keV)  = 2.341863e-08
S(50-150 keV) = 8.493915e-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 = 3.030787575824515E-01, IMY = -7.016731303969656E-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:
-239.696000 -0.020000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']

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

Time interval of the image:
-0.020000 2.956000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
  2.4511 -13.6646    2.0  43.1   53.6   0.3689   5.8 ------	UNKNOWN                       
 52.0033 -11.7026    2.1  34.1  134.5   0.1415   5.4 ------	UNKNOWN                       
 14.5889 -43.5374    1.2  17.3   13.0   0.1538   9.6 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
74.604590 286.204610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
318.7803 -14.6497    2.3  55.4    4.4   3.0664   5.0 ------	UNKNOWN

Analysis Summary

Notes:

Image

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

Light Curves

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:

Time averaged spectrum fit using the average DRM

Power-law model

Cutoff power-law model

1-s peak spectrum fit

Power-law model

Cutoff power-law model

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

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

Mask shadow pattern

Spacecraft aspect plot

Bright source in the pre-burst/pre-slew/post-slew images

Pre-burst image of 15-350 keV band

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

Post-slew image of 15-350 keV band

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