GRB241115A: 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: Wed Dec 18 16:25:35 EST 2024
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1267921
======================================================================

  Trigger: 01267921      Segment: 000

  BAT Trigger Time: 753369539.584   [s; MET]
      Trigger Stop: 753369540.096   [s; MET]
               UTC: 2024-11-15T13:18:25.044040    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 86.7650821753851   Dec: -0.662559979951746  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    18.15
     Image Trigger?:     NO
     Rate S/N Ratio:     61.8304132284428  [ if not an image trigger ]
     Image S/N Ratio:    18.15

  Analysis Position:   [ source = BAT ]
    RA: 86.7650821753851   Dec: -0.662559979951746  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 86.7712550200047   Dec: -0.665730132542879  [deg; J2000]  
        { 05h 47m 05.1s , -00d 39' 56.6" }
         +/- 0.900158610442437 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.356436077251799 [arcmin] (formal 1-sigma fit error)
    SNR: 35.3489806091933
 
  Angular difference between the analysis and refined position is 0.416336 arcmin
 
  Partial Coding Fraction: 0.78125    [ including projection effects ]

  Duration
     T90: 3.69999992847443 +/- 2.92357662972066
        Measured from: -0.248000025749207
                   to: 3.45199990272522     [s; relative to TRIGTIME]
     T50: 1.32399988174438 +/- 0.120929728318914
        Measured from: 0.320000052452087
                   to: 1.64399993419647     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.472000002861023     
                   to: 1.47200000286102     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.472000002861023     
                   to: 9.29200005531311     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.429788   0.683554   0.454594   0.074653
           0.022269   0.024484   0.020921   0.015615 [error]
 Peak      0.155575   0.289749   0.180414   0.030123
           0.009128   0.011127   0.009250   0.005855 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    9.764   -0.472    9.292
T90     3.700   -0.248    3.452
T50     1.324    0.320    1.644
Peak    1.000    0.472    1.472
 
 
====== 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: CPL)
 
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      -1.574    -0.076      0.075       -           -               -         1.12e-02     -5.05e-04          5.04e-04      56.620   57
CPL     -0.713    -0.347      0.378       73.032      -9.436        18.025      3.08e-02     -1.01e-02          1.69e-02      36.500   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: CPL)
 
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      -1.552     -0.076     0.075       -           -               -         4.23e-02     -2.11e-03          2.11e-03      96.950   57
CPL     -0.107     -0.396     0.438       63.561      -5.519         7.741      2.37e-01     -8.82e-02          1.61e-01      47.930   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-07  2.62e-07  3.52e-07  9.71e-07  1.02e-06  1.73e-06   erg/cm2
      90%_error_low -1.09e-08 -1.20e-08 -2.06e-08 -1.15e-07 -4.97e-08 -1.32e-07   erg/cm2
      90%_error_hi   1.11e-08  1.20e-08  2.05e-08  1.24e-07  4.99e-08  1.40e-07   erg/cm2
Peak flux       PL   1.83e+00  1.78e+00  1.22e+00  1.30e+00  5.35e+00  6.13e+00   ph/cm2/s
      90%_error_low -1.40e-01 -9.07e-02 -7.40e-02 -1.47e-01 -2.64e-01 -3.00e-01   ph/cm2/s
      90%_error_hi   1.43e-01  9.05e-02  7.38e-02  1.58e-01  2.64e-01  3.00e-01   ph/cm2/s
 
Fluence        CPL   1.30e-07  2.85e-07  3.65e-07  3.16e-07  9.57e-07  1.10e-06   erg/cm2
      90%_error_low -1.31e-08 -1.52e-08 -2.32e-08 -1.02e-07 -5.58e-08 -1.14e-07   erg/cm2
      90%_error_hi   1.33e-08  1.55e-08  2.33e-08  1.57e-07  5.61e-08  1.62e-07   erg/cm2
Peak flux      CPL   1.45e+00  2.06e+00  1.35e+00  3.66e-01  5.14e+00  5.22e+00   ph/cm2/s
      90%_error_low -1.65e-01 -1.20e-01 -9.09e-02 -1.05e-01 -2.70e-01 -2.89e-01   ph/cm2/s
      90%_error_hi   1.68e-01  1.22e-01  9.12e-02  1.37e-01  2.70e-01  2.94e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   86.7713    -0.6657   0.0054    20.8755   136.5733         1.6439127     35.349 TRIG_01267921                 
 
Foreground time interval of the image:
 -0.472   9.292 (delta_t =   9.764 [sec])
Background time interval of the image:
-239.584  -0.472 (delta_t = 239.112 [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   -0.472 sec. to    9.292 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.57397     ( -0.0758454   0.0753757 )
Norm@50keV  : 1.11646E-02    ( -0.000505222   0.000504026 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   56.62     using 59 bins.
 Reduced chi-squared = 0.993333
# Null hypothesis probability of 4.89e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 9.764 sec: 1.42342 ( -0.06437  0.06445 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.023e-06 ( -4.96564e-08  4.98681e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.472 sec. to    9.292 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.71284     ( -0.347071   0.377886 )
Epeak [keV] : 73.0320      ( -9.43604 18.0254 )
Norm@50keV  : 3.07548E-02    ( -0.0101361   0.0168979 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   36.50     using 59 bins.
 Reduced chi-squared = 0.651786
# Null hypothesis probability of 9.80e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 9.764 sec: 1.36630 ( -0.06799  0.06802 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.56727e-07 ( -5.58241e-08  5.61296e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    0.472 sec. to    1.472 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.55219     ( -0.075919   0.0752759 )
Norm@50keV  : 4.22709E-02    ( -0.00210958   0.00210506 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   96.95     using 59 bins.
 Reduced chi-squared = 1.70088
# Null hypothesis probability of 7.62e-04 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 5.35478 ( -0.26384  0.264 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.97878e-07 ( -2.12349e-08  2.13111e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.472 sec. to    1.472 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.107495     ( -0.396238   0.43838 )
Epeak [keV] : 63.5609      ( -5.51903 7.74144 )
Norm@50keV  : 0.236986    ( -0.0882412   0.160947 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.93     using 59 bins.
 Reduced chi-squared = 0.855893
# Null hypothesis probability of 7.70e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 5.14442 ( -0.26952  0.2697 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.66817e-07 ( -2.2689e-08  2.29096e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 3.7 sec.
Hardness ratio (energy fluence ratio) = 1.2817105476

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

S(15-50 keV)  = 4.146339e-07
S(50-150 keV) = 5.420901e-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 = -2.769737525344806E-01, IMY = -2.621660003891960E-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:
-239.584000 -0.472000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6024  22.0321    2.3  42.7  122.5   8.0253   5.0    2.0	Crab                          
138.5195  -4.8568    2.6  58.7 -159.1   9.1354   4.3 ------	UNKNOWN                       

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

Time interval of the image:
-0.472000 9.292000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.5964  21.8526    0.0  42.5  122.5  -0.1113  -0.6    9.9	Crab                          
 86.7712  -0.6657    0.3  20.9  136.6   1.6438  35.3 ------	UNKNOWN                       
130.7641   0.3887    2.2  53.7 -168.7   0.6362   5.3 ------	UNKNOWN                       
129.8009 -35.1212    2.7  45.7 -122.6   0.7414   4.4 ------	UNKNOWN                       
132.7786 -30.5116    2.8  48.0 -129.0   0.6564   4.1 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
91.316600 99.755100
100.416000 962.456000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6349  22.0225    0.4  22.9  141.8  35.7807  25.7    0.5	Crab                          
 56.0048   0.5789    2.8  30.8   61.5   8.9820   4.1 ------	UNKNOWN                       
 49.0340 -35.8737    2.9  49.6    9.9   7.4149   4.0 ------	UNKNOWN                       
 57.4677 -30.8473    3.4  41.0    9.1   5.3574   3.4 ------	UNKNOWN                       
123.1835  32.8830    3.2  48.0 -168.6   8.9987   3.6 ------	UNKNOWN                       
 63.6033 -48.6464    3.9  52.0  -11.5   6.8481   2.9 ------	UNKNOWN                       
134.4388   5.7592    3.0  48.0 -129.1  22.2157   3.9 ------	UNKNOWN