GRB240809A: 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 v2.48
    Process Start Time: Sat Oct 19 14:59:45 EDT 2024
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1247745
======================================================================

  Trigger: 01247745      Segment: 000

  BAT Trigger Time: 744885063.552   [s; MET]
      Trigger Stop: 744885064.064   [s; MET]
               UTC: 2024-08-09T08:30:29.592500    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 237.551195371051   Dec: -2.32115782967295  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    12.85
     Image Trigger?:     NO
     Rate S/N Ratio:     90.0777441991084  [ if not an image trigger ]
     Image S/N Ratio:    12.85

  Analysis Position:   [ source = BAT ]
    RA: 237.551195371051   Dec: -2.32115782967295  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 237.544931479342   Dec: -2.33040358419886  [deg; J2000]  
        { 15h 50m 10.8s , -02d 19' 49.5" }
         +/- 0.525320744268121 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.149945778008793 [arcmin] (formal 1-sigma fit error)
    SNR: 76.2977759642404
 
  Angular difference between the analysis and refined position is 0.669896 arcmin
 
  Partial Coding Fraction: 0.7265625    [ including projection effects ]

  Duration
     T90: 69.4399999380112 +/- 20.7138894422011
        Measured from: -2.8160001039505
                   to: 66.6239998340607     [s; relative to TRIGTIME]
     T50: 9.40799987316132 +/- 0.791636294227891
        Measured from: 2.11199998855591
                   to: 11.5199998617172     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 2.66799998283386     
                   to: 3.66799998283386     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -9.21600008010864     
                   to: 179.90399992466     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     3.362724   4.675108   4.529784   1.826276
           0.096306   0.095613   0.084952   0.072101 [error]
 Peak      0.263222   0.517400   0.615905   0.322682
           0.012543   0.016387   0.018018   0.016422 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  189.120   -9.216  179.904
T90    69.440   -2.816   66.624
T50     9.408    2.112   11.520
Peak    1.000    2.668    3.668
 
 
====== 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      -1.156    -0.047      0.047       -           -               -         4.99e-03     -1.19e-04          1.19e-04      59.640   57
CPL     -1.157    -0.041      0.054     9999.360    -9999.360      -9999.360      5.02e-03     -1.24e-04          1.09e-04      60.100   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      -0.802     -0.062     0.063       -           -               -         1.12e-01     -3.79e-03          3.78e-03      61.510   57
CPL     -0.798     -0.060     0.067     9999.340    -9999.340      -9999.340      1.12e-01     -3.70e-03          1.34e-02      61.650   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   8.73e-07  1.98e-06  3.56e-06  1.51e-05  9.69e-06  2.15e-05   erg/cm2
      90%_error_low -4.83e-08 -6.31e-08 -8.90e-08 -9.42e-07 -2.29e-07 -9.61e-07   erg/cm2
      90%_error_hi   4.96e-08  6.28e-08  8.87e-08  9.88e-07  2.29e-07  1.00e-06   erg/cm2
Peak flux       PL   2.37e+00  3.62e+00  4.15e+00  9.12e+00  1.28e+01  1.93e+01   ph/cm2/s
      90%_error_low -1.76e-01 -1.61e-01 -1.46e-01 -7.24e-01 -4.28e-01 -7.73e-01   ph/cm2/s
      90%_error_hi   1.81e-01  1.61e-01  1.45e-01  7.66e-01  4.28e-01  7.91e-01   ph/cm2/s
 
Fluence        CPL   6.56e-07  8.28e-07  8.01e-07  1.73e-06  2.77e-06  4.01e-06   erg/cm2
      90%_error_low -7.17e-08 -8.93e-08 -1.05e-07 -1.02e-06 -3.26e-07 -5.73e-07   erg/cm2
      90%_error_hi   7.45e-08  8.54e-08  8.66e-08  2.26e-07  2.56e-07  4.01e-07   erg/cm2
Peak flux      CPL   2.37e+00  6.75e-02  1.43e-03  4.01e+00  1.33e-02  4.01e+00   ph/cm2/s
      90%_error_low -1.79e-01 -6.75e-02 -1.43e-03 4.79e+00 -1.33e-02 -4.01e+00   ph/cm2/s
      90%_error_hi   1.75e-01  3.04e-01  1.69e-02  5.80e+00  1.43e-01  5.03e+00   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  237.5449    -2.3304   0.0025    28.3437   162.1724        10.7599069     76.298 TRIG_01247745                 
 
Foreground time interval of the image:
 -9.216  10.549 (delta_t =  19.765 [sec])
Background time interval of the image:
-239.552  -9.216 (delta_t = 230.336 [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   -9.216 sec. to  179.904 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.1556     ( -0.0469504   0.0472237 )
Norm@50keV  : 4.98747E-03    ( -0.000119502   0.000118853 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   59.64     using 59 bins.
 Reduced chi-squared = 1.04632
# Null hypothesis probability of 3.80e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 189.1 sec: 0.582032 ( -0.015246  0.015305 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.69374e-06 ( -2.28938e-07  2.29e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -9.216 sec. to  179.904 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.15058     ( -0.0418699   0.0539238 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 5.01207E-03    ( -0.000119492   0.00011371 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   60.05     using 59 bins.
 Reduced chi-squared = 1.07232
# Null hypothesis probability of 3.31e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 189.1 sec: 0.581802 ( -0.015247  0.015306 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.76905e-06 ( -3.26396e-07  2.55856e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    2.668 sec. to    3.668 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.801546     ( -0.0622467   0.0628261 )
Norm@50keV  : 0.111748    ( -0.00379384   0.00377676 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   61.51     using 59 bins.
 Reduced chi-squared = 1.07912
# Null hypothesis probability of 3.18e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 12.8426 ( -0.4277  0.4281 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.30518e-06 ( -4.79927e-08  4.8045e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    2.668 sec. to    3.668 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.797627     ( -0.0598357   0.0665123 )
Epeak [keV] : 9999.34      ( -9999.36 -9999.36 )
Norm@50keV  : 0.112487    ( -0.0037949   0.0132845 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   61.65     using 59 bins.
 Reduced chi-squared = 1.10089
# Null hypothesis probability of 2.81e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 1.33454E-02 ( -0.0133454  0.142652 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.31226e-06 ( -5.55357e-08  4.04665e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 69.44 sec.
Hardness ratio (energy fluence ratio) = 1.79556002214

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

S(15-50 keV)  = 2.8551215e-06
S(50-150 keV) = 6.838708e-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 = -5.135257878257191E-01, IMY = -1.651475167264640E-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:
-239.552000 -9.216000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9932 -15.6420    1.3  41.9  149.9   7.7117   8.8    0.8	Sco X-1                       
254.4102  35.3508    1.6  15.6   26.8   2.2159   7.2    2.4	Her X-1                       
268.1666  -1.4935    0.0  38.7  108.0   1.6449   1.4   12.3	SW J1753.5-0127               
280.4376  13.0112    3.2  40.2   78.1   5.8967   3.7 ------	UNKNOWN                       
203.3100   3.7671    3.3  41.4 -138.8   1.9012   3.5 ------	UNKNOWN                       
192.6121  53.5399    3.3  44.4  -61.3   5.0678   3.5 ------	UNKNOWN                       
191.9810  56.2036    2.7  45.7  -57.9   6.0936   4.3 ------	UNKNOWN                       

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

Time interval of the image:
-9.216000 10.548600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9793 -15.5977    6.4  41.8  149.9  -0.5333  -1.8    2.6	Sco X-1                       
254.4494  35.3432  182.0  15.7   26.9  -0.0088  -0.1    0.4	Her X-1                       
268.2129  -1.4764  137.3  38.7  108.0  -0.0370  -0.1    9.4	SW J1753.5-0127               
237.5449  -2.3304    0.2  28.3  162.2  10.7600  76.3 ------	UNKNOWN                       
238.3135  10.7050    2.7  15.3  163.1   0.5348   4.2 ------	UNKNOWN                       
209.3943 -11.6910    2.7  47.9 -160.7   1.1290   4.4 ------	UNKNOWN                       
223.8353  69.6039    2.5  44.7  -30.6   1.0439   4.5 ------	UNKNOWN                       
192.9298  51.5720    3.4  43.6  -63.9   2.2216   3.4 ------	UNKNOWN                       
191.8908  60.1911    2.1  47.3  -52.9   2.8995   5.4 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
76.348600 962.502800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
245.0007 -15.6329    0.5  15.2  136.3  32.3403  25.3    1.3	Sco X-1                       
254.4868  35.3484    3.5  40.9    6.0   7.0272   3.2    1.5	Her X-1                       
256.0260 -37.8530    2.8  39.4  141.5  15.7629   4.1    1.9	4U 1700-377                   
256.2680 -36.4868    6.2  38.3  140.1   6.6634   1.9    8.9	GX 349+2                      
262.9889 -24.8689   18.6  33.3  119.5   1.7027   0.6    7.5	GX 1+4                        
264.7630 -44.3182    4.7  48.4  138.8 -14.1514  -2.4    8.0	4U 1735-44                    
268.5244  -1.4309   10.8  31.0   73.6   2.8372   1.1    9.5	SW J1753.5-0127               
270.0925 -25.1974    0.0  38.8  113.8   9.5927   2.1   12.6	GX 5-1                        
270.2461 -25.7213    5.0  39.2  114.3  10.8085   2.3    3.3	GRS 1758-258                  
274.1603 -14.0501    5.3  38.0   94.8   8.6229   2.2    9.0	GX 17+2                       
262.8757 -33.9669    6.0  39.5  130.8   7.7474   1.9    9.7	GX 354-0                      
269.7160  -3.3753    2.9  32.1   77.4  10.9729   4.0 ------	UNKNOWN