GRB230606A: 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: Fri Sep 29 23:46:08 EDT 2023
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1173731
======================================================================

  Trigger: 01173731      Segment: 000

  BAT Trigger Time: 707703308.736   [s; MET]
      Trigger Stop: 707703310.784   [s; MET]
               UTC: 2023-06-06T00:14:37.322360    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 166.816687835473   Dec: 36.4846778033881  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.88
     Image Trigger?:     NO
     Rate S/N Ratio:     9.59166304662544  [ if not an image trigger ]
     Image S/N Ratio:    7.88

  Analysis Position:   [ source = BAT ]
    RA: 166.816687835473   Dec: 36.4846778033881  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 166.776906637782   Dec: 36.5037979692158  [deg; J2000]  
        { 11h 07m 06.5s , +36d 30' 13.7" }
         +/- 2.46745048146596 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.0679767706449 [arcmin] (formal 1-sigma fit error)
    SNR: 8.37073238382393
 
  Angular difference between the analysis and refined position is 2.235634 arcmin
 
  Partial Coding Fraction: 0.1523438    [ including projection effects ]

  Duration
     T90: 16.2560000419617 +/- 1.30701494300898
        Measured from: 0.0880000591278076
                   to: 16.3440001010895     [s; relative to TRIGTIME]
     T50: 13.0080000162125 +/- 10.3557952505818
        Measured from: 1.49600005149841
                   to: 14.5040000677109     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.924000024795532     
                   to: 1.92400002479553     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.263999938964844     
                   to: 16.9680000543594     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.306375   0.483378   0.552017   0.172361
           0.085266   0.091446   0.085416   0.080158 [error]
 Peak      0.044864   0.101783   0.139296   0.033223
           0.021240   0.023325   0.021975   0.020292 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   17.232   -0.264   16.968
T90    16.256    0.088   16.344
T50    13.008    1.496   14.504
Peak    1.000    0.924    1.924
 
 
====== 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      -1.177    -0.298      0.311       -           -               -         6.93e-03     -1.18e-03          1.17e-03      34.380   57
CPL     -0.964    -4.329      0.950      287.272      N/A           N/A         8.58e-03        N/A               N/A         34.420   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      -1.296     -0.353     0.355       -           -               -         2.25e-02     -4.90e-03          4.90e-03      67.030   57
CPL      1.643     -2.252     4.835       73.655     -13.928        47.539      3.68e-01     -3.68e-01          1.84e+01      61.300   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   1.13e-07  2.53e-07  4.47e-07  1.86e-06  1.22e-06  2.67e-06   erg/cm2
      90%_error_low -3.74e-08 -5.39e-08 -8.31e-08 -6.84e-07 -2.12e-07 -7.38e-07   erg/cm2
      90%_error_hi   4.23e-08  5.23e-08  8.14e-08  9.24e-07  2.12e-07  9.35e-07   erg/cm2
Peak flux       PL   7.62e-01  8.66e-01  7.06e-01  9.60e-01  2.69e+00  3.29e+00   ph/cm2/s
      90%_error_low -2.86e-01 -2.25e-01 -1.70e-01 -4.00e-01 -6.15e-01 -7.18e-01   ph/cm2/s
      90%_error_hi   3.35e-01  2.23e-01  1.68e-01  5.33e-01  6.24e-01  7.24e-01   ph/cm2/s
 
Fluence        CPL   1.11e-07  2.53e-07  4.50e-07  1.73e-06  1.22e-06  2.51e-06   erg/cm2
      90%_error_low -5.09e-08 -5.36e-08 -8.48e-08 -1.30e-06 -2.20e-07 -1.28e-06   erg/cm2
      90%_error_hi   3.10e-08  5.70e-08  1.08e-07  6.12e-07  2.14e-07  1.03e-06   erg/cm2
Peak flux      CPL   2.98e-01  8.69e-01  9.15e-01  2.26e-01  2.27e+00  2.31e+00   ph/cm2/s
      90%_error_low -2.98e-01 -3.60e-01 -2.37e-01 -2.26e-01 -6.70e-01 -6.99e-01   ph/cm2/s
      90%_error_hi   4.35e-01  2.93e-01  2.56e-01  4.00e-01  6.96e-01  7.96e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  166.7769    36.5038   0.0230    49.6989  -144.9846         1.7724579      8.371 TRIG_01173731                 
 
Foreground time interval of the image:
 -0.264  16.968 (delta_t =  17.232 [sec])
Background time interval of the image:
-208.835  -0.264 (delta_t = 208.571 [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   -0.264 sec. to   16.968 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.17664     ( -0.298174   0.31082 )
Norm@50keV  : 6.93141E-03    ( -0.0011809   0.00117099 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   34.38     using 59 bins.
 Reduced chi-squared = 0.603158
# Null hypothesis probability of 9.92e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 17.23 sec: 0.811035 ( -0.146431  0.14784 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.21993e-06 ( -2.11827e-07  2.12473e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.264 sec. to   16.968 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.15555     ( -3.13715   2.14147 )
Epeak [keV] : 55.4589      (   )
Norm@50keV  : 1.05589E-03    (     )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   33.30     using 59 bins.
 Reduced chi-squared = 0.594643
# Null hypothesis probability of 9.93e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 17.23 sec: 0.810418 ( -0.156731  0.148253 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.21783e-06 ( -2.19793e-07  2.13621e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    0.924 sec. to    1.924 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.29563     ( -0.352483   0.355852 )
Norm@50keV  : 2.25240E-02    ( -0.0049028   0.00489841 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   67.03     using 59 bins.
 Reduced chi-squared = 1.17596
# Null hypothesis probability of 1.71e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.68525 ( -0.615  0.62367 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.22828e-07 ( -5.05261e-08  5.09068e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.924 sec. to    1.924 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.64305     ( -2.26041   4.82659 )
Epeak [keV] : 73.6551      ( -13.9022 47.5646 )
Norm@50keV  : 0.367729    ( -0.371797   18.3521 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   61.30     using 59 bins.
 Reduced chi-squared = 1.09464
# Null hypothesis probability of 2.92e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.27455 ( -0.66997  0.69601 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.00106e-07 ( -5.29595e-08  5.48587e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 16.256 sec.
Hardness ratio (energy fluence ratio) = 1.76957928546

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

S(15-50 keV)  = 3.653876e-07
S(50-150 keV) = 8.54532e-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 = -9.656927480165931E-01, IMY = 6.765720113939392E-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:
-208.835400 -0.264000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.2692  35.4208   28.9  18.6   44.1  -0.2750  -0.4   10.3	Her X-1                       
299.5501  35.2386    5.6  50.1    7.1   2.5278   2.0    3.0	Cyg X-1                       
308.2022  40.7859    0.0  53.0   -3.5   0.8549   0.7   10.8	Cyg X-3                       
303.2599  29.3670    2.3  56.1   10.9  13.2213   5.0 ------	UNKNOWN                       
263.9029  42.6526    2.3  22.0   15.5   3.1977   4.9 ------	UNKNOWN                       
210.6405  50.6148    3.0  16.2 -131.3   2.2740   3.9 ------	UNKNOWN                       
163.0248  41.3799    2.6  49.7 -137.5  10.7328   4.4 ------	UNKNOWN                       

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

Time interval of the image:
-0.264000 16.968000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3207  35.1792    4.4  18.7   44.6   0.1781   2.6   11.9	Her X-1                       
299.5252  35.1182   10.5  50.2    7.2  -0.1801  -1.1    5.9	Cyg X-1                       
308.3139  40.9493    5.3  53.0   -3.8  -0.3720  -2.2    9.2	Cyg X-3                       
182.4943  22.3064    2.1  47.0 -171.2   0.6598   5.4 ------	UNKNOWN                       
166.7769  36.5038    1.4  49.7 -145.0   1.7727   8.4 ------	UNKNOWN                       
318.8484  71.3689    2.0  46.5  -43.7   1.0780   5.7 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
270.364590 962.386000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.6541  35.4078  191.9  35.4  165.5   0.0996   0.1   10.4	Her X-1                       
268.3816  -1.5543   11.9  40.2   99.8  -3.0200  -1.0    6.2	SW J1753.5-0127               
288.7593  10.7923   14.1  19.2   76.1  -1.1711  -0.8    9.5	GRS 1915+105                  
299.5790  35.2334    1.5   7.2 -102.2   8.3899   7.9    2.0	Cyg X-1                       
308.1887  41.0204    4.6  15.8  -90.4   3.0563   2.5    5.4	Cyg X-3                       
326.1555  38.4885    9.8  26.8  -65.4   1.7547   1.2   10.0	Cyg X-2                       
280.4666   0.8434    3.1  31.6   84.7   8.3882   3.7 ------	UNKNOWN                       
239.3151  44.3668    3.2  47.1  179.3  10.3638   3.6 ------	UNKNOWN                       
229.2214  54.2839    2.7  53.7 -167.9  14.7862   4.3 ------	UNKNOWN