GRB190926A: 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: Wed Nov 27 12:25:31 EST 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger926515
======================================================================

  Trigger: 00926515      Segment: 000

  BAT Trigger Time: 591184360   [s; MET]
      Trigger Stop: 591184424   [s; MET]
               UTC: 2019-09-26T09:52:16.353280    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 100.598926332506   Dec: 59.5111569925745  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.13
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    8.13

  Analysis Position:   [ source = BAT ]
    RA: 100.598926332506   Dec: 59.5111569925745  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 100.615496445917   Dec: 59.5317546515976  [deg; J2000]  
        { 06h 42m 27.7s , +59d 31' 54.3" }
         +/- 2.28201250794827 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.2323758029466 [arcmin] (formal 1-sigma fit error)
    SNR: 9.35913029757714
 
  Angular difference between the analysis and refined position is 1.334783 arcmin
 
  Partial Coding Fraction: 0.5    [ including projection effects ]

  Duration
     T90: 362.340000033379 +/- 19.6065119642314
        Measured from: 11.2079999446869
                   to: 373.547999978065     [s; relative to TRIGTIME]
     T50: 187.144000053406 +/- 116.639384614027
        Measured from: 47.3839999437332
                   to: 234.527999997139     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 52.9479999542236     
                   to: 53.9479999542236     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.00399994850158691     
                   to: 386.468000054359     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.839651   1.715415   0.941788   0.059635
           0.124655   0.128511   0.111524   0.098384 [error]
 Peak      0.032886   0.026849   0.007819   0.010941
           0.008310   0.008535   0.007016   0.006592 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  386.472   -0.004  386.468
T90   362.340   11.208  373.548
T50   187.144   47.384  234.528
Peak    1.000   52.948   53.948
 
 
====== 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      -2.114    -0.184      0.175       -           -               -         6.46e-04     -7.53e-05          7.34e-05      48.580   57
CPL     -1.997     1.997      1.997        1.670      N/A           N/A         7.27e-04        N/A               N/A         49.290   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      -2.016     -0.804     0.704       -           -               -         3.76e-03     -1.85e-03          1.72e-03      59.940   57
CPL     -2.037     -1.642     3.855       19.452      N/A           N/A         3.45e-03        N/A               N/A         59.870   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   5.69e-07  7.21e-07  6.66e-07  1.08e-06  2.32e-06  3.04e-06   erg/cm2
      90%_error_low -6.85e-08 -6.09e-08 -1.08e-07 -3.12e-07 -2.37e-07 -4.38e-07   erg/cm2
      90%_error_hi   7.02e-08  6.07e-08  1.10e-07  3.91e-07  2.42e-07  4.99e-07   erg/cm2
Peak flux       PL   2.55e-01  1.89e-01  9.36e-02  6.59e-02  5.68e-01  6.03e-01   ph/cm2/s
      90%_error_low -1.25e-01 -6.82e-02 -5.50e-02 -6.59e-02 -2.01e-01 -2.16e-01   ph/cm2/s
      90%_error_hi   1.30e-01  6.73e-02  6.06e-02  1.20e-01  2.01e-01  2.18e-01   ph/cm2/s
 
Fluence        CPL   5.62e-07  6.13e-07  4.98e-07  8.26e-07  1.94e-06  2.71e-06   erg/cm2
      90%_error_low -7.41e-08 -1.67e-07 -2.34e-07 -5.37e-07 -5.84e-07 -1.17e-06   erg/cm2
      90%_error_hi   7.39e-08  1.53e-07  2.61e-07  7.86e-07  6.02e-07  9.78e-07   erg/cm2
Peak flux      CPL     N/A      N/A      N/A      N/A      N/A      N/A     ph/cm2/s
      90%_error_low -1.25e-01 -6.82e-02 -5.50e-02 -6.59e-02 -2.01e-01 -2.16e-01   ph/cm2/s
      90%_error_hi   1.30e-01  6.73e-02  6.06e-02  1.20e-01  2.01e-01  2.18e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  100.6155    59.5318   0.0207    28.6391   114.6996         1.3595012      9.359 TRIG_00926515                 
 
Foreground time interval of the image:
 -0.004  73.301 (delta_t =  73.305 [sec])
Background time interval of the image:
-239.000  -0.004 (delta_t = 238.996 [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   -0.004 sec. to  386.468 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.11366     ( -0.184299   0.174981 )
Norm@50keV  : 6.45798E-04    ( -7.53461e-05   7.33857e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          48.58 using 59 PHA bins.
# Reduced chi-squared =         0.8523 for     57 degrees of freedom 
# Null hypothesis probability =   7.786621e-01
 
Photon flux (15-150 keV)    in 386.5 sec: 0.102300 ( -0.0084917  0.008498 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.32268e-06 ( -2.36606e-07  2.42038e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.004 sec. to  386.468 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.35184     ( 1.99695   1.99695 )
Epeak [keV] : 138.094      (   )
Norm@50keV  : 4.83717E-04    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.39 using 59 PHA bins.
# Reduced chi-squared =         0.8463 for     56 degrees of freedom 
# Null hypothesis probability =   7.867058e-01
 
Photon flux (15-150 keV)    in 386.5 sec: 9.44822E-02 ( -0.0200185  0.0076368 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.94205e-06 ( -5.84079e-07  6.01614e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   52.948 sec. to   53.948 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.01617     ( -0.804118   0.704185 )
Norm@50keV  : 3.76126E-03    ( -0.0018459   0.00171615 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.94 using 59 PHA bins.
# Reduced chi-squared =          1.052 for     57 degrees of freedom 
# Null hypothesis probability =   3.694547e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.568468 ( -0.200805  0.20081 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.47232e-08 ( -1.47435e-08  1.60787e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   52.948 sec. to   53.948 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.50649     ( -1.17142   4.32553 )
Epeak [keV] : 178.237      (   )
Norm@50keV  : 2.01477E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.54 using 59 PHA bins.
# Reduced chi-squared =          1.063 for     56 degrees of freedom 
# Null hypothesis probability =   3.481197e-01
 
Photon flux (15-150 keV)    in 1 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 362.34 sec.
Hardness ratio (energy fluence ratio) = 0.924272727689

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

S(15-50 keV)  = 1.2900365e-06
S(50-150 keV) = 1.0326049e-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 = -2.281950291976579E-01, IMY = -4.961409639792215E-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:
-239.000000 -0.004000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 94.0989   9.3854    4.2  48.5   33.7   2.2506   2.7 ------	UNKNOWN                       
239.4870  74.3761    2.4  54.3  171.1   4.6108   4.8 ------	UNKNOWN                       
147.0277  24.0910    2.9  19.3  -60.0   0.9918   4.0 ------	UNKNOWN                       

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

Time interval of the image:
-0.004000 73.300590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 85.1398  32.6334    2.0  40.9   67.4   2.2928   5.7 ------	UNKNOWN                       
100.6155  59.5317    1.2  28.6  114.7   1.3606   9.4 ------	UNKNOWN                       
158.1571  13.8421    2.4  33.3  -69.7   0.9182   4.9 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
123.500610 824.800600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6185  22.0145    0.4  39.4   18.1  26.2804  31.7    0.8	Crab                          
322.3217  66.2601    2.8  50.5  152.5   9.5747   4.1 ------	UNKNOWN                       
 65.3641  72.4796    2.8  18.8  140.3   2.4663   4.2 ------	UNKNOWN                       
100.6509  59.4946    2.7   0.0  -55.9   2.3629   4.3 ------	UNKNOWN                       
251.4224  60.5152    3.0  57.9 -170.7  12.7151   3.8 ------	UNKNOWN                       
115.3714   1.6950    3.2  58.9  -24.5  12.2005   3.6 ------	UNKNOWN