GRB190816A: 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: Tue Oct  8 22:34:15 EDT 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger920783
======================================================================

  Trigger: 00920783      Segment: 000

  BAT Trigger Time: 587659368   [s; MET]
      Trigger Stop: 587659448   [s; MET]
               UTC: 2019-08-16T14:42:24.578600    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 341.193592693739   Dec: -29.7399634001357  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.26
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    8.26

  Analysis Position:   [ source = BAT ]
    RA: 341.193592693739   Dec: -29.7399634001357  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 341.181560239531   Dec: -29.7446124365791  [deg; J2000]  
        { 22h 44m 43.6s , -29d 44' 40.6" }
         +/- 1.66865306377129 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.543288707815764 [arcmin] (formal 1-sigma fit error)
    SNR: 14.6370175649813
 
  Angular difference between the analysis and refined position is 0.686105 arcmin
 
  Partial Coding Fraction: 0.3085938    [ including projection effects ]

  Duration
     T90: 375.759999990463 +/- 92.2201941781066
        Measured from: -118.447999954224
                   to: 257.31200003624     [s; relative to TRIGTIME]
     T50: 150.447999954224 +/- 10.7873257921812
        Measured from: 10.0800000429153
                   to: 160.527999997139     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 151.572000026703     
                   to: 152.572000026703     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -206.480000019073     
                   to: 341.552000045776     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     4.884625   5.586613   4.365112   1.478426
           0.282218   0.293387   0.256139   0.215530 [error]
 Peak      0.051310   0.060884   0.046232   0.007398
           0.012464   0.014083   0.011942   0.009179 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  548.032 -206.480  341.552
T90   375.760 -118.448  257.312
T50   150.448   10.080  160.528
Peak    1.000  151.572  152.572
 
 
====== 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      -1.619    -0.107      0.106       -           -               -         1.91e-03     -1.12e-04          1.12e-04      44.330   57
CPL     -1.620    -0.104      0.109     9999.360    -9999.360      -9999.360      1.91e-03     -3.40e-04          8.91e-04      44.340   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      -1.917     -0.446     0.386       -           -               -         8.87e-03     -2.75e-03          2.65e-03      73.170   57
CPL     -0.429     -1.566     2.422       47.860      N/A           N/A         5.91e-02        N/A               N/A         70.530   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   1.49e-06  2.55e-06  3.32e-06  8.77e-06  9.76e-06  1.61e-05   erg/cm2
      90%_error_low -1.47e-07 -1.51e-07 -2.62e-07 -1.42e-06 -6.15e-07 -1.63e-06   erg/cm2
      90%_error_hi   1.52e-07  1.51e-07  2.61e-07  1.59e-06  6.20e-07  1.77e-06   erg/cm2
Peak flux       PL   5.46e-01  4.30e-01  2.27e-01  1.75e-01  1.28e+00  1.38e+00   ph/cm2/s
      90%_error_low -1.78e-01 -1.09e-01 -8.65e-02 -1.17e-01 -3.25e-01 -3.54e-01   ph/cm2/s
      90%_error_hi   1.89e-01  1.09e-01  8.80e-02  1.47e-01  3.25e-01  3.56e-01   ph/cm2/s
 
Fluence        CPL   1.50e-06  2.54e-06  3.32e-06  9.19e-06  9.79e-06  1.62e-05   erg/cm2
      90%_error_low    N/A    -1.53e-07 -2.87e-07    N/A    -7.10e-07 -3.64e-06   erg/cm2
      90%_error_hi     N/A     1.85e-07  3.08e-07    N/A     5.01e-07  8.79e-07   erg/cm2
Peak flux      CPL   4.62e-01  5.18e-01  2.49e-01  4.56e-02  1.27e+00  1.27e+00   ph/cm2/s
      90%_error_low -2.06e-01 -1.44e-01     N/A   -4.56e-02 -3.23e-01 -3.26e-01   ph/cm2/s
      90%_error_hi   2.12e-01  1.55e-01     N/A    1.59e-01  3.24e-01  3.37e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  341.1816   -29.7446   0.0132    29.6778    55.4667         4.8690528     14.637 TRIG_00920783                 
 
Foreground time interval of the image:
-12.499  83.701 (delta_t =  96.200 [sec])
Background time interval of the image:

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 -206.480 sec. to  341.552 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.61867     ( -0.10657   0.105697 )
Norm@50keV  : 1.90910E-03    ( -0.000112469   0.000111916 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.33 using 59 PHA bins.
# Reduced chi-squared =         0.7778 for     57 degrees of freedom 
# Null hypothesis probability =   8.895547e-01
 
Photon flux (15-150 keV)    in 548 sec: 0.246776 ( -0.014475  0.014512 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.76383e-06 ( -6.15311e-07  6.19596e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from -206.480 sec. to  341.552 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.61978     ( -0.10545   0.108336 )
Epeak [keV] : 9999.36      ( -9999.36 -9999.36 )
Norm@50keV  : 1.90717E-03    ( -0.000345459   0.000885329 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.34 using 59 PHA bins.
# Reduced chi-squared =         0.7919 for     56 degrees of freedom 
# Null hypothesis probability =   8.695895e-01
 
Photon flux (15-150 keV)    in 548 sec: 0.247419 ( -0.017141  0.01528 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.79402e-06 ( -7.10159e-07  5.00605e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from  151.572 sec. to  152.572 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.9173     ( -0.446182   0.386008 )
Norm@50keV  : 8.86763E-03    ( -0.00275317   0.002649 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          73.17 using 59 PHA bins.
# Reduced chi-squared =          1.284 for     57 degrees of freedom 
# Null hypothesis probability =   7.320159e-02
 
Photon flux (15-150 keV)    in 1 sec: 1.28213 ( -0.324947  0.32498 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.15511e-08 ( -2.39846e-08  2.47824e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  151.572 sec. to  152.572 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.428527     ( -1.56307   2.42453 )
Epeak [keV] : 47.8596      (   )
Norm@50keV  : 5.91427E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          70.53 using 59 PHA bins.
# Reduced chi-squared =          1.259 for     56 degrees of freedom 
# Null hypothesis probability =   9.157560e-02
 
Photon flux (15-150 keV)    in 1 sec: 1.26699 ( -0.323326  0.32398 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.7707e-08 ( -2.30948e-08  2.48724e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 375.76 sec.
Hardness ratio (energy fluence ratio) = 1.30256704391

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

S(15-50 keV)  = 4.045816e-06
S(50-150 keV) = 5.718136e-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 = 3.230544599709423E-01, IMY = -4.694627845241600E-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:
 

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

Time interval of the image:
-12.499380 83.700610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
326.2914 -28.0396    3.4  42.8   57.5   2.3256   3.4 ------	UNKNOWN                       
354.7226  15.3589    2.7  44.1  135.7   4.4944   4.3 ------	UNKNOWN                       
316.8564 -45.0342    2.6  50.1   33.8   3.1599   4.5 ------	UNKNOWN                       
341.1816 -29.7446    0.8  29.7   55.5   4.8692  14.6 ------	UNKNOWN                       
 29.6782 -16.4251    2.3  16.6 -132.7   0.9628   5.1 ------	UNKNOWN                       
 40.1332  23.3534    1.8  54.1 -167.0   4.2461   6.4 ------	UNKNOWN                       
 45.6648   2.9771    2.5  41.1 -144.2   1.4731   4.6 ------	UNKNOWN                       
 48.8767 -25.4627    2.7  31.5  -97.5   1.2209   4.3 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
97.900600 196.700610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
343.9737   6.4639    2.8  40.8  115.5   2.9633   4.1 ------	UNKNOWN                       
341.1671 -29.7336    0.7  29.6   52.7   6.5193  17.5 ------	UNKNOWN                       
358.2333  -1.3642    2.3  25.7  127.0   1.5574   5.1  133.9	UNKNOWN                       
 18.3420 -63.6454    2.0  41.2  -19.9   1.8194   5.8 ------	UNKNOWN                       
 56.3678   4.7862    2.9  50.3 -134.0   4.3543   4.0 ------	UNKNOWN