GRB071020: 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: Mon Jan 20 06:17:16 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger294835
======================================================================

  Trigger: 00294835      Segment: 000

  BAT Trigger Time: 214556549.248   [s; MET]
      Trigger Stop: 214556549.76   [s; MET]
               UTC: 2007-10-20T07:02:26.944040    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 119.663756248614   Dec: 32.8612387898184  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    22.19
     Image Trigger?:     NO
     Rate S/N Ratio:     180.449438901871  [ if not an image trigger ]
     Image S/N Ratio:    22.19

  Analysis Position:   [ source = BAT ]
    RA: 119.663756248614   Dec: 32.8612387898184  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 119.665521187257   Dec: 32.8564805640906  [deg; J2000]  
        { 07h 58m 39.7s , +32d 51' 23.3" }
         +/- 0.534531951215422 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.130464190437688 [arcmin] (formal 1-sigma fit error)
    SNR: 74.4264703058347
 
  Angular difference between the analysis and refined position is 0.299031 arcmin
 
  Partial Coding Fraction: 0.90625    [ including projection effects ]

  Duration
     T90: 4.30000001192093 +/- 0.582697189430528
        Measured from: -2.45199999213219
                   to: 1.84800001978874     [s; relative to TRIGTIME]
     T50: 1.96400001645088 +/- 0.0610573254426089
        Measured from: -1.71599999070168
                   to: 0.248000025749207     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.356000006198883     
                   to: 0.643999993801117     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -3.05199998617172     
                   to: 7.53200000524521     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.693403   1.150737   1.148796   0.382400
           0.019082   0.021416   0.020674   0.015987 [error]
 Peak      0.174595   0.346047   0.437000   0.160085
           0.007311   0.009310   0.010415   0.007876 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   10.584   -3.052    7.532
T90     4.300   -2.452    1.848
T50     1.964   -1.716    0.248
Peak    1.000   -0.356    0.644
 
 
====== 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      -1.082    -0.043      0.043       -           -               -         2.11e-02     -4.79e-04          4.78e-04      32.740   57
CPL     -0.997    -0.123     -0.037      663.891    -663.891      -663.891      2.29e-02     -2.16e-03          3.11e-03      33.000   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      -0.768     -0.052     0.053       -           -               -         7.32e-02     -2.16e-03          2.15e-03      35.820   57
CPL     -0.690     -0.096     0.199      997.891    -997.891      -997.891      7.91e-02     -2.25e-03          1.56e-02      35.540   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   1.93e-07  4.58e-07  8.65e-07  3.97e-06  2.34e-06  5.48e-06   erg/cm2
      90%_error_low -9.58e-09 -1.33e-08 -2.12e-08 -2.32e-07 -5.50e-08 -2.40e-07   erg/cm2
      90%_error_hi   9.79e-09  1.32e-08  2.11e-08  2.42e-07  5.51e-08  2.49e-07   erg/cm2
Peak flux       PL   8.53e-04  1.04e-02  1.35e-01  1.18e+01  6.13e-01  1.19e+01   ph/cm2/s
      90%_error_low     N/A       N/A       N/A       N/A       N/A       N/A     ph/cm2/s
      90%_error_hi      N/A       N/A       N/A       N/A       N/A       N/A     ph/cm2/s
 
Fluence        CPL   1.92e-07  4.59e-07  8.70e-07  3.99e-06  2.34e-06  5.19e-06   erg/cm2
      90%_error_low -1.45e-08 -9.02e-09 -1.28e-08 -1.04e-06 -5.76e-08 -6.45e-07   erg/cm2
      90%_error_hi   8.47e-09  1.34e-08  2.67e-08  2.12e-07  6.12e-08  3.47e-07   erg/cm2
Peak flux      CPL   1.48e+00  2.35e+00  2.78e+00  6.10e+00  8.40e+00  1.23e+01   ph/cm2/s
      90%_error_low -1.37e-01 -9.44e-02 -8.65e-02 -1.37e+00 -2.57e-01 -1.01e+00   ph/cm2/s
      90%_error_hi   1.02e-01  8.84e-02  1.02e-01  3.87e-01  2.44e-01  6.67e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  119.6655    32.8565   0.0026    15.0644   -63.2484         3.4454502     74.426 TRIG_00294835                 
 
Foreground time interval of the image:
 -3.052   7.532 (delta_t =  10.584 [sec])
Background time interval of the image:
-239.248  -3.052 (delta_t = 236.196 [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   -3.052 sec. to    7.532 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.08201     ( -0.0425053   0.0426832 )
Norm@50keV  : 2.10697E-02    ( -0.000479065   0.000477953 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          32.74 using 59 PHA bins.
# Reduced chi-squared =         0.5744 for     57 degrees of freedom 
# Null hypothesis probability =   9.959144e-01
 
Photon flux (15-150 keV)    in 10.58 sec: 2.43986 ( -0.05832  0.05849 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.34448e-06 ( -5.50014e-08  5.50521e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -3.052 sec. to    7.532 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.07778     ( -0.0415905   0.0442974 )
Epeak [keV] : 9992.03      ( -9989.11 -9989.11 )
Norm@50keV  : 2.11922E-02    ( -0.000477482   0.00479523 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          32.69 using 59 PHA bins.
# Reduced chi-squared =         0.5838 for     56 degrees of freedom 
# Null hypothesis probability =   9.945901e-01
 
Photon flux (15-150 keV)    in 10.58 sec: 2.43343 ( -0.06708  0.05932 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.33709e-06 ( -5.76109e-08  6.11665e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   -0.356 sec. to    0.644 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.767647     ( -0.0522742   0.0526889 )
Norm@50keV  : 7.31767E-02    ( -0.00216072   0.00215139 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          35.82 using 59 PHA bins.
# Reduced chi-squared =         0.6283 for     57 degrees of freedom 
# Null hypothesis probability =   9.873832e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.613032 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.67062e-07 ( -2.708e-08  2.7149e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.356 sec. to    0.644 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.690465     ( -0.0963529   0.198723 )
Epeak [keV] : 997.891      ( -999.553 -999.553 )
Norm@50keV  : 7.91022E-02    ( -0.00222299   0.0155895 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          35.54 using 59 PHA bins.
# Reduced chi-squared =         0.6346 for     56 degrees of freedom 
# Null hypothesis probability =   9.850723e-01
 
Photon flux (15-150 keV)    in 1 sec: 8.40468 ( -0.2566  0.24385 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.64848e-07 ( -2.86291e-08  2.589e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 4.3 sec.
Hardness ratio (energy fluence ratio) = 1.88951361249

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

S(15-50 keV)  = 6.505754e-07
S(50-150 keV) = 1.6938742e-06

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 = 1.211522604034570E-01, IMY = 2.403453886967238E-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:
-239.248000 -3.052000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6305  22.0182    0.3  24.5   51.8  10.1283  45.4    0.3	Crab                          
 76.5971   9.8420    2.5  38.3   48.7   1.8025   4.5 ------	UNKNOWN                       
102.4794 -16.3022    1.9  56.4    4.2   5.6935   6.0 ------	UNKNOWN                       
133.2913  29.5943    2.9  26.7  -72.9   0.9119   3.9 ------	UNKNOWN                       

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

Time interval of the image:
-3.052000 7.532000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.7687  22.0906   11.2  24.3   51.7   0.0583   1.0    8.8	Crab                          
 93.8715  34.6733    2.6   9.1   60.3   0.1899   4.5 ------	UNKNOWN                       
119.6655  32.8565    0.2  15.1  -63.2   3.4454  74.4 ------	UNKNOWN                       
115.2856  -8.8203    2.4  50.1  -12.3   0.5560   4.9 ------	UNKNOWN                       
137.8438  40.2680    2.2  26.3  -98.4   0.3065   5.2 ------	UNKNOWN                       
192.6699  64.4124    2.7  54.3 -144.5   1.0375   4.3 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
50.452600 962.838100
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6263  22.0143    0.3  33.6   69.3  36.9734  37.9    0.4	Crab                          
 71.3060  58.2211    2.8  41.0  132.0   5.5920   4.1 ------	UNKNOWN                       
 83.5241  53.4070    2.6  32.8  128.5   3.8614   4.5 ------	UNKNOWN                       
 86.7982  44.1821    2.4  27.8  112.5   3.7723   4.9 ------	UNKNOWN                       
 92.0993   4.5546    2.5  38.2   37.1   3.7503   4.6 ------	UNKNOWN                       
149.2800  73.1483    3.3  43.0 -179.0   2.8592   3.5 ------	UNKNOWN                       
136.0712  34.7215    2.7  13.8 -113.4   2.0115   4.2 ------	UNKNOWN