GRB220302A: 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: Sun Oct 23 23:39:57 EDT 2022
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1094950
======================================================================

  Trigger: 01094950      Segment: 000

  BAT Trigger Time: 667899648.192   [s; MET]
      Trigger Stop: 667899652.288   [s; MET]
               UTC: 2022-03-02T07:40:19.483320    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 301.431936947381   Dec: 49.3889348270439  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.47
     Image Trigger?:     NO
     Rate S/N Ratio:     9.79795897113271  [ if not an image trigger ]
     Image S/N Ratio:    7.47

  Analysis Position:   [ source = BAT ]
    RA: 301.431936947381   Dec: 49.3889348270439  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 301.398540470341   Dec: 49.4074921603604  [deg; J2000]  
        { 20h 05m 35.6s , +49d 24' 27.0" }
         +/- 2.73845148288855 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.22395091858171 [arcmin] (formal 1-sigma fit error)
    SNR: 7.2129208136069
 
  Angular difference between the analysis and refined position is 1.714737 arcmin
 
  Partial Coding Fraction: 0.4453125    [ including projection effects ]

  Duration
     T90: 6.59200000762939 +/- 2.09326531433751
        Measured from: -1.56000006198883
                   to: 5.03199994564056     [s; relative to TRIGTIME]
     T50: 2.73600006103516 +/- 1.3268428140899
        Measured from: 0.615999937057495
                   to: 3.35199999809265     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.363999962806702     
                   to: 1.3639999628067     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.86400008201599     
                   to: 5.38399994373322     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.176902   0.154039   0.183094   0.030558
           0.035265   0.036764   0.032858   0.029864 [error]
 Peak      0.043073   0.038558   0.056087   0.021156
           0.013544   0.014177   0.013025   0.010980 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    7.248   -1.864    5.384
T90     6.592   -1.560    5.032
T50     2.736    0.616    3.352
Peak    1.000    0.364    1.364
 
 
====== 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: 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      -1.409    -0.361      0.362       -           -               -         5.21e-03     -1.04e-03          1.04e-03      49.180   57
CPL     -1.347    -3.087      1.336      556.909    -556.909      -556.909      5.58e-03     -1.39e-03          -5.58e-03      49.210   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      -1.322     -0.461     0.485       -           -               -         1.08e-02     -2.82e-03          2.83e-03      44.130   57
CPL     -1.326     -0.457     0.495     9999.350    -9999.350      -9999.350      1.08e-02     -2.81e-03          2.86e-03      44.140   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   4.43e-08  8.61e-08  1.30e-07  4.23e-07  3.64e-07  6.83e-07   erg/cm2
      90%_error_low -1.54e-08 -1.92e-08 -3.27e-08 -1.94e-07 -7.89e-08 -2.23e-07   erg/cm2
      90%_error_hi   1.70e-08  1.86e-08  3.19e-08  2.82e-07  7.96e-08  2.94e-07   erg/cm2
Peak flux       PL   3.75e-01  4.20e-01  3.36e-01  4.46e-01  1.30e+00  1.58e+00   ph/cm2/s
      90%_error_low -1.78e-01 -1.36e-01 -1.01e-01 -2.30e-01 -3.61e-01 -4.15e-01   ph/cm2/s
      90%_error_hi   2.06e-01  1.30e-01  9.79e-02  3.42e-01  3.64e-01  4.17e-01   ph/cm2/s
 
Fluence        CPL   4.54e-08  8.58e-08  1.29e-07  4.33e-07  3.65e-07  6.42e-07   erg/cm2
      90%_error_low -1.98e-08 -1.89e-08 -3.23e-08 -3.44e-07 -7.58e-08 -3.07e-07   erg/cm2
      90%_error_hi   1.83e-08  2.14e-08  3.69e-08  1.42e-07  6.75e-08  3.20e-07   erg/cm2
Peak flux      CPL   3.93e-01  4.11e-01  3.27e-01  4.43e-01  1.31e+00  1.66e+00   ph/cm2/s
      90%_error_low     N/A       N/A   -3.27e-01     N/A       N/A   -1.66e+00   ph/cm2/s
      90%_error_hi      N/A       N/A    1.46e-01     N/A       N/A    4.46e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  301.3985    49.4075   0.0267    41.3484   -21.8456         0.5387006      7.213 TRIG_01094950                 
 
Foreground time interval of the image:
 -1.864   5.384 (delta_t =   7.248 [sec])
Background time interval of the image:
-239.192  -1.864 (delta_t = 237.328 [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   -1.864 sec. to    5.384 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.40921     ( -0.360645   0.361643 )
Norm@50keV  : 5.21334E-03    ( -0.00103793   0.00103505 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   49.18     using 59 bins.
 Reduced chi-squared = 0.862807
# Null hypothesis probability of 7.60e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 7.248 sec: 0.636239 ( -0.131284  0.132025 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.64484e-07 ( -7.89032e-08  7.96439e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -1.864 sec. to    5.384 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.40635     ( -3.01609   1.40669 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 5.23176E-03    ( -0.00104327   -0.00523179 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   49.18     using 59 bins.
 Reduced chi-squared = 0.878214
# Null hypothesis probability of 7.29e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 7.248 sec: 0.639194 ( -0.145695  0.136288 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.65038e-07 ( -7.58054e-08  6.75136e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    0.364 sec. to    1.364 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.3224     ( -0.461171   0.484881 )
Norm@50keV  : 1.08146E-02    ( -0.00282423   0.00282662 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   44.13     using 59 bins.
 Reduced chi-squared = 0.774211
# Null hypothesis probability of 8.94e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 1.29570 ( -0.361279  0.36386 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.06309e-07 ( -2.94048e-08  2.95536e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.364 sec. to    1.364 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.32582     ( -0.458369   0.493864 )
Epeak [keV] : 9999.35      ( -9999.36 -9999.36 )
Norm@50keV  : 1.08375E-02    ( -0.00283563   0.00283616 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   44.14     using 59 bins.
 Reduced chi-squared = 0.788214
# Null hypothesis probability of 8.74e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 1.30568 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.06574e-07 ( -3.08524e-08  2.55312e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = N/A sec.
Hardness ratio (energy fluence ratio) = N/A

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

S(15-50 keV)  = N/A
S(50-150 keV) = N/A

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 = 8.168240404729624E-01, IMY = 3.274607089242439E-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:
-239.192000 -1.864000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5900  35.1928    1.5  53.3  -32.4  13.0518   7.6    0.5	Cyg X-1                       
308.1752  40.8870    5.1  44.8  -35.3   1.6849   2.3    4.9	Cyg X-3                       
326.3636  38.1659    0.0  38.6  -54.7  -0.6885  -1.0   13.0	Cyg X-2                       
105.7542  59.6679    2.5  39.9  102.1   4.4357   4.5 ------	UNKNOWN                       
144.4215  73.1973    3.8  40.1   70.9   3.5548   3.1 ------	UNKNOWN                       

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

Time interval of the image:
-1.864000 5.384000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5327  35.1982    4.3  53.4  -32.4  -0.5719  -2.6    2.8	Cyg X-1                       
308.1377  40.8638    6.0  44.8  -35.2  -0.1799  -1.9    5.5	Cyg X-3                       
326.0590  38.3661    2.9  38.5  -54.2   0.3172   4.1    5.9	Cyg X-2                       
301.3990  49.4077    1.6  41.3  -21.8   0.5382   7.2 ------	UNKNOWN                       
342.2822  37.9208    2.3  32.1  -73.3   0.3430   5.1 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
621.108630 962.876000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6418  22.0035    0.8  36.0  126.6  11.5168  13.7    0.8	Crab                          
348.1361  42.0443    2.5  43.4  -50.4   5.1995   4.6 ------	UNKNOWN