GRB170804A: 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 Aug 28 18:12:34 EDT 2017
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger766194
======================================================================

  Trigger: 00766194      Segment: 000

  BAT Trigger Time: 523540916.864   [s; MET]
      Trigger Stop: 523540929.024   [s; MET]
               UTC: 2017-08-04T12:01:37.389340    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 6.43307870586649   Dec: -64.7481285423807  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.82
     Image Trigger?:     NO
     Rate S/N Ratio:     10  [ if not an image trigger ]
     Image S/N Ratio:    8.82

  Analysis Position:   [ source = BAT ]
    RA: 6.43307870586649   Dec: -64.7481285423807  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 6.40451321446312   Dec: -64.7787913676821  [deg; J2000]  
        { 00h 25m 37.1s , -64d 46' 43.6" }
         +/- 1.3449336188282 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.490708702159481 [arcmin] (formal 1-sigma fit error)
    SNR: 19.9186556365311
 
  Angular difference between the analysis and refined position is 1.979581 arcmin
 
  Partial Coding Fraction: 0.7578125    [ including projection effects ]

  Duration
     T90: 56.4799998998642 +/- 18.6804381880922
        Measured from: 3.85600000619888
                   to: 60.3359999060631     [s; relative to TRIGTIME]
     T50: 17.9719999432564 +/- 4.81683216431091
        Measured from: 13.3959999680519
                   to: 31.3679999113083     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 25.0999999642372     
                   to: 26.0999999642372     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 1.97999995946884     
                   to: 78.9319999814034     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.682647   0.783560   0.600960   0.089731
           0.057039   0.059947   0.053174   0.048740 [error]
 Peak      0.038386   0.037302   0.013952   0.015227
           0.006837   0.007390   0.006550   0.005594 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   76.952    1.980   78.932
T90    56.480    3.856   60.336
T50    17.972   13.396   31.368
Peak    1.000   25.100   26.100
 
 
====== 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      -1.682    -0.147      0.144       -           -               -         1.86e-03     -1.64e-04          1.62e-04      45.580   57
CPL     -1.218    -0.522      0.629       79.584     -23.431       -79.584      3.26e-03     -1.48e-03          3.63e-03      43.510   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      -2.070     -0.425     0.376       -           -               -         5.77e-03     -1.68e-03          1.61e-03      77.150   57
CPL     -1.972      N/A       N/A          13.072      N/A           N/A         6.54e-03        N/A               N/A         77.210   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   2.16e-07  3.56e-07  4.43e-07  1.10e-06  1.32e-06  2.11e-06   erg/cm2
      90%_error_low -2.76e-08 -2.91e-08 -5.26e-08 -2.48e-07 -1.23e-07 -2.99e-07   erg/cm2
      90%_error_hi   2.85e-08  2.91e-08  5.26e-08  2.93e-07  1.25e-07  3.35e-07   erg/cm2
Peak flux       PL   4.12e-01  2.97e-01  1.41e-01  9.49e-02  8.95e-01  9.45e-01   ph/cm2/s
      90%_error_low -1.08e-01 -6.17e-02 -5.15e-02 -5.23e-02 -1.79e-01 -1.94e-01   ph/cm2/s
      90%_error_hi   1.11e-01  6.09e-02  5.46e-02  8.22e-02  1.79e-01  1.97e-01   ph/cm2/s
 
Fluence        CPL   2.03e-07  3.74e-07  4.50e-07  5.39e-07  1.27e-06  1.57e-06   erg/cm2
      90%_error_low -3.24e-08 -3.63e-08 -5.63e-08 -2.91e-07 -1.37e-07 -3.25e-07   erg/cm2
      90%_error_hi   3.27e-08  1.91e-08  5.67e-08  6.46e-07  1.39e-07  6.70e-07   erg/cm2
Peak flux      CPL   4.07e-01  2.88e-01  1.31e-01  1.11e-01  8.60e-01  9.47e-01   ph/cm2/s
      90%_error_low -1.29e-01 -1.57e-01     N/A   -6.78e-02 -3.49e-01     N/A     ph/cm2/s
      90%_error_hi   1.15e-01  1.38e-01     N/A    4.04e-02  2.10e-01     N/A     ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
    6.4045   -64.7788   0.0096    32.4178   -24.5918         2.2153231     19.919 TRIG_00766194                 
 
Foreground time interval of the image:
  1.980  56.437 (delta_t =  54.457 [sec])
Background time interval of the image:
-196.163   1.980 (delta_t = 198.143 [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    1.980 sec. to   78.932 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.68206     ( -0.147042   0.144096 )
Norm@50keV  : 1.85501E-03    ( -0.00016416   0.000162434 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.58 using 59 PHA bins.
# Reduced chi-squared =         0.7996 for     57 degrees of freedom 
# Null hypothesis probability =   8.615141e-01
 
Photon flux (15-150 keV)    in 76.95 sec: 0.244851 ( -0.020089  0.020109 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.32379e-06 ( -1.23102e-07  1.24614e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.980 sec. to   78.932 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.21848     ( -0.521878   0.629304 )
Epeak [keV] : 79.5838      ( -23.4308 -79.5838 )
Norm@50keV  : 3.26076E-03    ( -0.00148255   0.00363391 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.51 using 59 PHA bins.
# Reduced chi-squared =         0.7769 for     56 degrees of freedom 
# Null hypothesis probability =   8.883077e-01
 
Photon flux (15-150 keV)    in 76.95 sec: 0.239672 ( -0.021036  0.021008 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.27148e-06 ( -1.36834e-07  1.38555e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   25.100 sec. to   26.100 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.07013     ( -0.424995   0.376049 )
Norm@50keV  : 5.77310E-03    ( -0.00168008   0.00161137 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          77.15 using 59 PHA bins.
# Reduced chi-squared =          1.353 for     57 degrees of freedom 
# Null hypothesis probability =   3.901242e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.895171 ( -0.179204  0.179239 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.35032e-08 ( -1.36347e-08  1.43953e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   25.100 sec. to   26.100 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.97223     (       )
Epeak [keV] : 13.0723      (   )
Norm@50keV  : 6.54174E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          77.21 using 59 PHA bins.
# Reduced chi-squared =          1.379 for     56 degrees of freedom 
# Null hypothesis probability =   3.164270e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.859814 ( -0.348796  0.210446 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 56.48 sec.
Hardness ratio (energy fluence ratio) = 1.2465797138

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

S(15-50 keV)  = 5.719604e-07
S(50-150 keV) = 7.518211e-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 = 5.774520083058524E-01, IMY = 2.642784950702782E-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:
-196.163410 1.980000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
335.7284  -3.9062    2.5  36.3  118.2   1.8965   4.7 ------	UNKNOWN                       
323.2061 -23.4079    2.8  33.1   77.7   1.5180   4.2 ------	UNKNOWN                       
336.7960 -17.9702    2.1  25.1  101.1   1.2828   5.4 ------	UNKNOWN                       
332.8133 -82.4392    2.6  50.7  -14.7   1.6282   4.4 ------	UNKNOWN                       
 16.4912 -54.8421    3.6  25.2  -42.4   0.6481   3.2 ------	UNKNOWN                       
 27.8267   5.4038    2.0  46.6 -158.5   2.2267   5.7 ------	UNKNOWN                       
 41.5978   2.4976    3.1  53.1 -142.2   3.6872   3.7 ------	UNKNOWN                       
 45.3319 -13.7940    2.3  45.7 -122.3   3.8439   5.0 ------	UNKNOWN                       

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

Time interval of the image:
1.980000 56.436580
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
356.5144   8.2915    2.1  41.0  156.4   0.9459   5.6  539.4	UNKNOWN                       
332.2022 -50.2495    2.2  26.7   21.6   0.5139   5.1 ------	UNKNOWN                       
  6.4045 -64.7788    0.6  32.4  -24.6   2.2155  19.9 ------	UNKNOWN                       
 22.8485   3.6717    2.1  42.5 -163.2   0.7917   5.4 ------	UNKNOWN                       
 36.3978 -42.7351    2.0  30.6  -79.1   0.8668   5.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
111.036600 962.266300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
186.6494 -62.8045    2.9  52.4  -28.4   6.5364   4.0    2.1	GX 301-2                      
 44.2440 -25.0511    2.6  46.5 -158.5   5.2695   4.5 ------	UNKNOWN                       
 56.3717 -46.6719    3.4  32.2 -128.1   2.7351   3.4 ------	UNKNOWN