GRB240419B: 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 15:24:36 EDT 2024
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1223072
======================================================================

  Trigger: 01223072      Segment: 000

  BAT Trigger Time: 735222205.632   [s; MET]
      Trigger Stop: 735222209.728   [s; MET]
               UTC: 2024-04-19T12:22:52.334300    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 325.876862975223   Dec: 4.23355449629783  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.25
     Image Trigger?:     NO
     Rate S/N Ratio:     8.48528137423857  [ if not an image trigger ]
     Image S/N Ratio:    8.25

  Analysis Position:   [ source = BAT ]
    RA: 325.876862975223   Dec: 4.23355449629783  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 325.891340787182   Dec: 4.23239703192644  [deg; J2000]  
        { 21h 43m 33.9s , +04d 13' 56.6" }
         +/- 1.4564373462282 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.605752933416152 [arcmin] (formal 1-sigma fit error)
    SNR: 17.7764227735703
 
  Angular difference between the analysis and refined position is 0.869078 arcmin
 
  Partial Coding Fraction: 0.4335938    [ including projection effects ]

  Duration
     T90: 144.551999926567 +/- 12.2242134366755
        Measured from: -10.3679999113083
                   to: 134.184000015259     [s; relative to TRIGTIME]
     T50: 104.975999951363 +/- 4.82916479206583
        Measured from: 11.5960000753403
                   to: 116.572000026703     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 116.284000039101     
                   to: 117.284000039101     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -24.6200000047684     
                   to: 161.080000042915     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     2.541661   2.938325   1.780743   0.471992
           0.108164   0.111593   0.095662   0.081224 [error]
 Peak      0.073467   0.108203   0.068959   0.020285
           0.006970   0.007341   0.006433   0.004845 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  185.700  -24.620  161.080
T90   144.552  -10.368  134.184
T50   104.976   11.596  116.572
Peak    1.000  116.284  117.284
 
 
====== 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      -1.799    -0.087      0.086       -           -               -         2.57e-03     -1.27e-04          1.26e-04      44.270   57
CPL     -1.633    -0.236      0.344      104.956     -42.698      -104.956      3.14e-03     -6.73e-04          1.57e-03      43.500   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      -1.586     -0.141     0.138       -           -               -         1.62e-02     -1.40e-03          1.39e-03      56.030   57
CPL     -0.826     -0.617     0.727       73.529     -16.501       103.300      4.06e-02     -2.10e-02          5.60e-02      51.500   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   8.08e-07  1.24e-06  1.42e-06  3.13e-06  4.40e-06  6.60e-06   erg/cm2
      90%_error_low -6.18e-08 -5.77e-08 -9.52e-08 -4.24e-07 -2.21e-07 -5.07e-07   erg/cm2
      90%_error_hi   6.32e-08  5.76e-08  9.53e-08  4.68e-07  2.22e-07  5.39e-07   erg/cm2
Peak flux       PL   7.25e-01  6.94e-01  4.62e-01  4.79e-01  2.08e+00  2.36e+00   ph/cm2/s
      90%_error_low -9.32e-02 -5.76e-02 -5.09e-02 -9.80e-02 -1.68e-01 -1.94e-01   ph/cm2/s
      90%_error_hi   9.66e-02  5.74e-02  5.07e-02  1.12e-01  1.68e-01  1.94e-01   ph/cm2/s
 
Fluence        CPL   7.88e-07  1.26e-06  1.43e-06  2.38e-06  4.33e-06  5.86e-06   erg/cm2
      90%_error_low -7.29e-08 -6.94e-08 -9.78e-08 -9.48e-07 -2.56e-07 -9.85e-07   erg/cm2
      90%_error_hi   7.37e-08  7.07e-08  9.86e-08  8.77e-07  2.50e-07  9.58e-07   erg/cm2
Peak flux      CPL   6.44e-01  7.48e-01  4.82e-01  2.09e-01  2.01e+00  2.08e+00   ph/cm2/s
      90%_error_low -1.14e-01 -7.26e-02 -5.71e-02 -1.01e-01 -1.78e-01 -2.10e-01   ph/cm2/s
      90%_error_hi   1.16e-01  7.49e-02  5.78e-02  1.97e-01  1.77e-01  2.52e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  325.8913     4.2324   0.0108    39.9619    11.8350         4.1081163     17.776 TRIG_01223072                 
 
Foreground time interval of the image:
-24.620  49.869 (delta_t =  74.489 [sec])
Background time interval of the image:
-79.931 -24.620 (delta_t =  55.311 [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  -24.620 sec. to  161.080 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.79909     ( -0.0867423   0.0857981 )
Norm@50keV  : 2.57317E-03    ( -0.000126587   0.00012584 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   44.27     using 59 bins.
 Reduced chi-squared = 0.776667
# Null hypothesis probability of 8.91e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 185.7 sec: 0.354469 ( -0.01688  0.016915 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.39979e-06 ( -2.20602e-07  2.21806e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -24.620 sec. to  161.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.63334     ( -0.235639   0.343946 )
Epeak [keV] : 104.956      ( -42.6992 -104.957 )
Norm@50keV  : 3.14206E-03    ( -0.000673442   0.00157133 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   43.50     using 59 bins.
 Reduced chi-squared = 0.776786
# Null hypothesis probability of 8.89e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 185.7 sec: 0.351013 ( -0.018115  0.01812 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.33283e-06 ( -2.55909e-07  2.49772e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from  116.284 sec. to  117.284 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.58624     ( -0.14122   0.138439 )
Norm@50keV  : 1.62217E-02    ( -0.00139728   0.00138554 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   56.03     using 59 bins.
 Reduced chi-squared = 0.982982
# Null hypothesis probability of 5.11e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.07584 ( -0.16821  0.16832 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.51988e-07 ( -1.41148e-08  1.42805e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  116.284 sec. to  117.284 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.825574     ( -0.617601   0.727336 )
Epeak [keV] : 73.5289      ( -16.4939 103.308 )
Norm@50keV  : 4.06429E-02    ( -0.0210435   0.0559821 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   51.50     using 59 bins.
 Reduced chi-squared = 0.919643
# Null hypothesis probability of 6.46e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.01023 ( -0.17756  0.17654 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.42702e-07 ( -1.58784e-08  1.61234e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 144.552 sec.
Hardness ratio (energy fluence ratio) = 1.14947623243

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

S(15-50 keV)  = 2.0469159e-06
S(50-150 keV) = 2.3529025e-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 = 8.201534568808309E-01, IMY = -1.718620511270201E-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:
-79.931400 -24.620000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5286  35.1882    1.7  35.5   78.3   1.8217   6.7    3.1	Cyg X-1                       
308.0528  40.8775    5.0  27.4   85.0   0.4017   2.3    5.2	Cyg X-3                       
326.1010  38.2495    6.0  14.3   69.0  -0.2039  -1.9    5.5	Cyg X-2                       
 73.5927  66.3009    2.2  53.2 -167.6   1.4418   5.2 ------	UNKNOWN                       
354.3809  15.1999    2.4  26.8  -39.5   0.5435   4.9 ------	UNKNOWN                       

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

Time interval of the image:
-24.620000 49.868600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.8047  35.1015    0.0  35.3   78.0   0.4089   1.2   12.1	Cyg X-1                       
307.9345  40.8052    0.0  27.5   84.9  -0.3010  -1.3   11.9	Cyg X-3                       
326.1204  38.2628    4.1  14.3   69.0   0.4388   2.9    4.3	Cyg X-2                       
325.8914   4.2324    0.6  40.0   11.8   4.1082  17.8 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
136.068600 789.368600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
288.6883  11.0373    6.8  37.4  113.6  -4.0901  -1.7    8.5	GRS 1915+105                  
299.5946  35.2141    0.7  39.4  156.2  21.7101  15.5    0.8	Cyg X-1                       
308.1266  40.9169    5.6  40.0  169.9   2.8280   2.0    2.3	Cyg X-3                       
326.1665  38.4720    8.7  34.3 -168.7  -1.2450  -1.3    9.0	Cyg X-2                       
307.5750 -38.1965    3.0  45.7   31.1   7.4645   3.8 ------	UNKNOWN                       
340.1664  62.5746    3.1  59.3 -161.5  22.6625   3.7 ------	UNKNOWN                       
  3.2929  38.1649    3.1  48.1 -129.1  14.4155   3.7 ------	UNKNOWN