GRB181003A: 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: Fri Oct 19 17:58:03 EDT 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger865179
======================================================================

  Trigger: 00865179      Segment: 000

  BAT Trigger Time: 560236284.928   [s; MET]
      Trigger Stop: 560236289.024   [s; MET]
               UTC: 2018-10-03T05:11:03.236400    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 52.5688373282527   Dec: -34.0233528334788  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.68
     Image Trigger?:     NO
     Rate S/N Ratio:     8.24621125123532  [ if not an image trigger ]
     Image S/N Ratio:    7.68

  Analysis Position:   [ source = BAT ]
    RA: 52.5688373282527   Dec: -34.0233528334788  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 52.4817343038973   Dec: -33.9907483281737  [deg; J2000]  
        { 03h 29m 55.6s , -33d 59' 26.7" }
         +/- 1.74807077043468 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.883354005220151 [arcmin] (formal 1-sigma fit error)
    SNR: 13.6963708637414
 
  Angular difference between the analysis and refined position is 4.753543 arcmin
 
  Partial Coding Fraction: 0.96875    [ including projection effects ]

  Duration
     T90: 25.4919999837875 +/- 4.76236281484229
        Measured from: -8.60000002384186
                   to: 16.8919999599457     [s; relative to TRIGTIME]
     T50: 10.5999999046326 +/- 3.67706407972848
        Measured from: -2.3199999332428
                   to: 8.27999997138977     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.86400008201599     
                   to: 2.86400008201599     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -11.1959999799728     
                   to: 18.0080000162125     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.230145   0.372503   0.206360  -0.004176
           0.032856   0.035212   0.031999   0.029946 [error]
 Peak      0.022280   0.030664   0.024810  -0.003140
           0.006019   0.006549   0.006072   0.005533 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   29.204  -11.196   18.008
T90    25.492   -8.600   16.892
T50    10.600   -2.320    8.280
Peak    1.000    1.864    2.864
 
 
====== 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      -1.550    -0.197      0.192       -           -               -         1.80e-03     -2.34e-04          2.32e-04      58.610   57
CPL      0.184    -0.971      1.239       56.192      -9.200        19.107      1.60e-02     -1.60e-02          5.90e-02      47.700   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      -1.681     -0.455     0.408       -           -               -         4.45e-03     -1.32e-03          1.26e-03      44.950   57
CPL     -0.578     -1.560     2.213       57.327     -57.327       -57.327      1.82e-02     -1.82e-02          2.95e-01      43.620   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   7.03e-08  1.25e-07  1.71e-07  4.83e-07  4.94e-07  8.50e-07   erg/cm2
      90%_error_low -1.20e-08 -1.49e-08 -2.90e-08 -1.47e-07 -6.98e-08 -1.79e-07   erg/cm2
      90%_error_hi   1.24e-08  1.48e-08  2.93e-08  1.84e-07  7.14e-08  2.10e-07   erg/cm2
Peak flux       PL   2.18e-01  1.97e-01  1.23e-01  1.17e-01  5.87e-01  6.55e-01   ph/cm2/s
      90%_error_low -7.28e-02 -4.80e-02 -4.56e-02 -6.65e-02 -1.43e-01 -1.68e-01   ph/cm2/s
      90%_error_hi   7.76e-02  4.80e-02  4.66e-02  1.03e-01  1.43e-01  1.73e-01   ph/cm2/s
 
Fluence        CPL   5.75e-08  1.52e-07  1.69e-07  5.91e-08  4.25e-07  4.37e-07   erg/cm2
      90%_error_low -1.45e-08 -2.08e-08 -3.76e-08 -4.01e-08 -6.83e-08 -7.82e-08   erg/cm2
      90%_error_hi   1.46e-08  2.16e-08  3.61e-08  1.04e-07  7.53e-08  1.21e-07   erg/cm2
Peak flux      CPL   1.92e-01  2.24e-01  1.27e-01  3.49e-02  5.70e-01  5.78e-01   ph/cm2/s
      90%_error_low -8.58e-02 -6.20e-02     N/A   -3.49e-02 -1.43e-01 -1.49e-01   ph/cm2/s
      90%_error_hi   8.72e-02  6.59e-02     N/A    1.14e-01  1.44e-01  1.88e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   52.4817   -33.9907   0.0141    12.1987    48.4752         0.9111584     13.696 TRIG_00865179                 
 
Foreground time interval of the image:
-11.196  18.008 (delta_t =  29.204 [sec])
Background time interval of the image:
-239.928 -11.196 (delta_t = 228.732 [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  -11.196 sec. to   18.008 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.55037     ( -0.197043   0.191828 )
Norm@50keV  : 1.79729E-03    ( -0.000234263   0.000231611 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.61 using 59 PHA bins.
# Reduced chi-squared =          1.028 for     57 degrees of freedom 
# Null hypothesis probability =   4.161632e-01
 
Photon flux (15-150 keV)    in 29.2 sec: 0.227557 ( -0.026891  0.026892 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.94108e-07 ( -6.98079e-08  7.13925e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -11.196 sec. to   18.008 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.184135     ( -0.970846   1.2386 )
Epeak [keV] : 56.1921      ( -9.20013 19.1067 )
Norm@50keV  : 1.60119E-02    ( -0.0160121   0.0590128 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.70 using 59 PHA bins.
# Reduced chi-squared =         0.8518 for     56 degrees of freedom 
# Null hypothesis probability =   7.772946e-01
 
Photon flux (15-150 keV)    in 29.2 sec: 0.214686 ( -0.027334  0.027481 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.24866e-07 ( -6.8281e-08  7.52986e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.864 sec. to    2.864 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.681     ( -0.454853   0.408398 )
Norm@50keV  : 4.44692E-03    ( -0.00131783   0.00126382 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.95 using 59 PHA bins.
# Reduced chi-squared =         0.7886 for     57 degrees of freedom 
# Null hypothesis probability =   8.761726e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.586758 ( -0.143111  0.143155 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.12449e-08 ( -1.23966e-08  1.30901e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.864 sec. to    2.864 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.578199     ( -1.55919   2.21404 )
Epeak [keV] : 57.3271      ( -57.3387 -57.3387 )
Norm@50keV  : 1.82387E-02    ( -0.0182256   0.295304 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.62 using 59 PHA bins.
# Reduced chi-squared =         0.7789 for     56 degrees of freedom 
# Null hypothesis probability =   8.859190e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.569669 ( -0.142647  0.144377 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.76929e-08 ( -1.20085e-08  1.38406e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 25.492 sec.
Hardness ratio (energy fluence ratio) = 1.3657767791

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

S(15-50 keV)  = 1.9544239e-07
S(50-150 keV) = 2.986766e-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 = 1.433178867959028E-01, IMY = -1.618503740141366E-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:
-239.928000 -11.196000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6361  22.0138    1.5  55.2  177.8   7.9667   7.8    0.2	Crab                          
 36.2195 -69.5128    2.6  42.5   -6.7   1.6379   4.4 ------	UNKNOWN                       

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

Time interval of the image:
-11.196000 18.008000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.5997  21.9781    9.9  55.1  177.8  -0.3800  -1.2    2.9	Crab                          
 34.7568 -52.4455    2.0  31.7   15.6   0.4896   5.7 ------	UNKNOWN                       
 52.4817 -33.9908    0.8  12.2   48.5   0.9104  13.7 ------	UNKNOWN                       
123.8360 -68.3125    2.0  49.9  -45.8   1.9973   5.8 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
178.372590 815.372590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
112.1549  51.9046    4.4  35.2  105.4   2.6563   2.6 ------	UNKNOWN                       
134.3593   1.4515    2.6  28.8  -11.5   2.1007   4.5 ------	UNKNOWN                       
166.0013  21.1182    3.0  18.9 -111.2   2.0985   3.9 ------	UNKNOWN                       
213.2945  45.6734    2.5  54.8 -165.6   6.4146   4.5 ------	UNKNOWN                       
134.4419 -24.7700    2.2  53.8  -23.8   7.3882   5.3 ------	UNKNOWN                       
158.6271 -17.7796    3.0  47.0  -53.3   9.4987   3.9 ------	UNKNOWN                       
178.9031   1.2914    4.4  40.8  -92.5   5.7664   2.6 ------	UNKNOWN