GRB181203A: 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 Dec 17 14:06:16 EST 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger874475
======================================================================

  Trigger: 00874475      Segment: 000

  BAT Trigger Time: 565531749.888   [s; MET]
      Trigger Stop: 565531750.912   [s; MET]
               UTC: 2018-12-03T12:08:47.866980    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 108.368923591337   Dec: -39.7690778271218  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.24
     Image Trigger?:     NO
     Rate S/N Ratio:     14.8323969741913  [ if not an image trigger ]
     Image S/N Ratio:    8.24

  Analysis Position:   [ source = BAT ]
    RA: 108.368923591337   Dec: -39.7690778271218  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 108.337169327052   Dec: -39.7783831251791  [deg; J2000]  
        { 07h 13m 20.9s , -39d 46' 42.2" }
         +/- 1.29356544984538 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.413170845025074 [arcmin] (formal 1-sigma fit error)
    SNR: 21.058171347652
 
  Angular difference between the analysis and refined position is 1.567162 arcmin
 
  Partial Coding Fraction: 0.8359375    [ including projection effects ]

  Duration
     T90: 15.0599999427795 +/- 1.76298946536287
        Measured from: -0.812000036239624
                   to: 14.2479999065399     [s; relative to TRIGTIME]
     T50: 8.39199995994568 +/- 0.950696620199982
        Measured from: 1.49199998378754
                   to: 9.88399994373322     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.0239999294281     
                   to: 2.0239999294281     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.7960000038147     
                   to: 15.8519999980927     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.463087   0.544931   0.320919   0.074589
           0.034495   0.036360   0.031140   0.026034 [error]
 Peak      0.031797   0.050128   0.046322   0.022838
           0.008435   0.008997   0.007820   0.006418 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   17.648   -1.796   15.852
T90    15.060   -0.812   14.248
T50     8.392    1.492    9.884
Peak    1.000    1.024    2.024
 
 
====== 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      -1.814    -0.147      0.143       -           -               -         4.75e-03     -4.28e-04          4.22e-04      56.000   57
CPL     -1.629    -0.562      0.612       89.358      N/A           N/A         6.01e-03        N/A               N/A         55.670   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      -1.204     -0.366     0.383       -           -               -         9.05e-03     -1.66e-03          1.66e-03      57.840   57
CPL     -1.227     -0.343     0.414     9999.360    -9999.360      -9999.360      9.02e-03     -1.59e-03          -9.02e-03      57.880   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   1.44e-07  2.18e-07  2.48e-07  5.39e-07  7.71e-07  1.15e-06   erg/cm2
      90%_error_low -1.69e-08 -1.68e-08 -3.06e-08 -1.25e-07 -7.01e-08 -1.57e-07   erg/cm2
      90%_error_hi   1.73e-08  1.68e-08  3.08e-08  1.48e-07  7.11e-08  1.75e-07   erg/cm2
Peak flux       PL   2.81e-01  3.37e-01  2.93e-01  4.34e-01  1.06e+00  1.34e+00   ph/cm2/s
      90%_error_low -1.04e-01 -7.88e-02 -6.57e-02 -1.84e-01 -2.03e-01 -2.60e-01   ph/cm2/s
      90%_error_hi   1.17e-01  7.43e-02  6.31e-02  2.64e-01  2.03e-01  2.71e-01   ph/cm2/s
 
Fluence        CPL   1.41e-07  2.23e-07  2.48e-07  3.84e-07  7.56e-07  9.96e-07   erg/cm2
      90%_error_low -1.91e-08 -2.00e-08 -3.18e-08 -2.34e-07 -8.25e-08 -2.51e-07   erg/cm2
      90%_error_hi   1.86e-08  2.24e-08  3.17e-08  3.34e-07  8.13e-08  2.13e-07   erg/cm2
Peak flux      CPL   2.90e-01  3.38e-01  2.89e-01  4.46e-01  1.07e+00  1.34e+00   ph/cm2/s
      90%_error_low -1.16e-01 -8.18e-02 -6.42e-02     N/A   -2.18e-01 -2.77e-01   ph/cm2/s
      90%_error_hi   1.11e-01  7.61e-02  6.92e-02     N/A    2.05e-01  2.76e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  108.3372   -39.7784   0.0091    21.6201   156.9337         1.4409948     21.058 TRIG_00874475                 
 
Foreground time interval of the image:
 -1.796  15.852 (delta_t =  17.648 [sec])
Background time interval of the image:
-298.187 -277.496 (delta_t =  20.691 [sec])
-239.888  -1.796 (delta_t = 238.092 [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   -1.796 sec. to   15.852 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.81411     ( -0.147382   0.143235 )
Norm@50keV  : 4.74708E-03    ( -0.000428446   0.000421681 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.00 using 59 PHA bins.
# Reduced chi-squared =         0.9825 for     57 degrees of freedom 
# Null hypothesis probability =   5.126057e-01
 
Photon flux (15-150 keV)    in 17.65 sec: 0.657787 ( -0.051072  0.0511 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.71107e-07 ( -7.0145e-08  7.11498e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -1.796 sec. to   15.852 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.62861     ( -0.562442   0.611539 )
Epeak [keV] : 89.3582      (   )
Norm@50keV  : 6.01123E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          55.67 using 59 PHA bins.
# Reduced chi-squared =         0.9941 for     56 degrees of freedom 
# Null hypothesis probability =   4.873852e-01
 
Photon flux (15-150 keV)    in 17.65 sec: 0.652226 ( -0.053692  0.05351 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.56214e-07 ( -8.25016e-08  8.12662e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.024 sec. to    2.024 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.20429     ( -0.365754   0.383372 )
Norm@50keV  : 9.05344E-03    ( -0.00165752   0.00165735 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.84 using 59 PHA bins.
# Reduced chi-squared =          1.015 for     57 degrees of freedom 
# Null hypothesis probability =   4.439689e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.06333 ( -0.20264  0.20346 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.17508e-08 ( -1.90097e-08  1.92203e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.024 sec. to    2.024 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.20155     ( -0.344458   0.412172 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 9.09559E-03    ( -0.00166515   -0.00909559 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.86 using 59 PHA bins.
# Reduced chi-squared =          1.033 for     56 degrees of freedom 
# Null hypothesis probability =   4.063147e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.06976 ( -0.218146  0.20498 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.09829e-08 ( -1.82887e-08  1.99116e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 15.06 sec.
Hardness ratio (energy fluence ratio) = 1.13754859909

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

S(15-50 keV)  = 3.620541e-07
S(50-150 keV) = 4.090611e-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 = -3.646480396765555E-01, IMY = -1.552817912817654E-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:
-298.187400 -277.496100
-239.888000 -1.796000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.4639 -40.5188   11.5  35.4 -169.6   0.3349   1.0    3.7	Vela X-1                      
170.0526 -60.7291    0.0  41.7 -122.8  -1.1338  -1.7   10.0	Cen X-3                       
 38.3144 -27.1524    2.5  44.3   34.0   2.8592   4.6 ------	UNKNOWN                       
 53.0195 -29.0431    2.2  35.3   49.0   2.9732   5.3 ------	UNKNOWN                       
156.7354 -37.4734    3.0  49.5 -156.0   2.5124   3.9 ------	UNKNOWN                       
159.6455 -38.9094    3.0  50.1 -152.5   2.6223   3.9 ------	UNKNOWN                       

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

Time interval of the image:
-1.796000 15.852000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5094 -40.6794    5.6  35.4 -169.4   0.1787   2.1    7.5	Vela X-1                      
170.1437 -60.4841    9.3  41.8 -123.1   0.1908   1.2    9.8	Cen X-3                       
108.3372 -39.7784    0.5  21.6  156.9   1.4411  21.1 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
60.012590 962.201700
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.4888 -40.6407    5.5  20.7 -131.1   1.7595   2.1    5.5	Vela X-1                      
102.5984   0.0856    3.6  40.2  118.8   9.0329   3.3 ------	UNKNOWN                       
121.8017   6.1901    3.7  47.6  146.0   8.2856   3.1 ------	UNKNOWN                       
 75.0653 -75.7406    3.6  38.9  -39.8   3.4552   3.2 ------	UNKNOWN