GRB231230A: 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 Mar  9 14:13:41 EST 2024
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1205319
======================================================================

  Trigger: 01205319      Segment: 000

  BAT Trigger Time: 725592581.376   [s; MET]
      Trigger Stop: 725592584.448   [s; MET]
               UTC: 2023-12-30T01:29:08.738220    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 245.197505172734   Dec: 58.1197216671146  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.14
     Image Trigger?:     NO
     Rate S/N Ratio:     25.9807621135332  [ if not an image trigger ]
     Image S/N Ratio:    9.14

  Analysis Position:   [ source = BAT ]
    RA: 245.197505172734   Dec: 58.1197216671146  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 245.222209460033   Dec: 58.1319349239161  [deg; J2000]  
        { 16h 20m 53.3s , +58d 07' 55.0" }
         +/- 1.1261470279977 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.435356904789673 [arcmin] (formal 1-sigma fit error)
    SNR: 25.6691271590809
 
  Angular difference between the analysis and refined position is 1.072208 arcmin
 
  Partial Coding Fraction: 0.3554688    [ including projection effects ]

  Duration
     T90: 15.2400000095367 +/- 0.9222234150588
        Measured from: 1.12799990177155
                   to: 16.3679999113083     [s; relative to TRIGTIME]
     T50: 7.74799990653992 +/- 1.40020569319693
        Measured from: 5.51999998092651
                   to: 13.2679998874664     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 7.63599991798401     
                   to: 8.63599991798401     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.251999974250793     
                   to: 17.2639999389648     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.558266   0.995242   1.039707   0.295158
           0.050440   0.055867   0.050415   0.042873 [error]
 Peak      0.037110   0.094308   0.100093   0.037481
           0.012327   0.014561   0.012939   0.010700 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   17.012    0.252   17.264
T90    15.240    1.128   16.368
T50     7.748    5.520   13.268
Peak    1.000    7.636    8.636
 
 
====== 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      -1.277    -0.095      0.096       -           -               -         1.27e-02     -7.04e-04          7.03e-04      41.720   57
CPL     -0.888    -0.378      0.416      162.298     -55.861      1805.852      1.90e-02     -5.99e-03          9.85e-03      38.670   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      -1.257     -0.241     0.248       -           -               -         1.90e-02     -2.91e-03          2.90e-03      47.210   57
CPL     -0.348     -1.002     1.475      102.234    -102.234      -102.234      4.96e-02     -4.96e-02          1.75e-01      45.220   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   2.24e-07  4.71e-07  7.77e-07  2.90e-06  2.14e-06  4.38e-06   erg/cm2
      90%_error_low -2.40e-08 -3.12e-08 -4.87e-08 -3.86e-07 -1.24e-07 -4.16e-07   erg/cm2
      90%_error_hi   2.49e-08  3.10e-08  4.85e-08  4.25e-07  1.24e-07  4.46e-07   erg/cm2
Peak flux       PL   6.19e-01  7.20e-01  6.02e-01  8.51e-01  2.25e+00  2.79e+00   ph/cm2/s
      90%_error_low -1.72e-01 -1.35e-01 -9.92e-02 -2.53e-01 -3.65e-01 -4.26e-01   ph/cm2/s
      90%_error_hi   1.89e-01  1.32e-01  9.81e-02  3.07e-01  3.68e-01  4.28e-01   ph/cm2/s
 
Fluence        CPL   2.04e-07  4.84e-07  8.11e-07  1.80e-06  2.11e-06  3.30e-06   erg/cm2
      90%_error_low -3.02e-08 -3.44e-08 -5.89e-08 -6.31e-07 -1.30e-07 -6.31e-07   erg/cm2
      90%_error_hi   3.10e-08  3.49e-08  5.98e-08  1.06e-06  1.29e-07  1.05e-06   erg/cm2
Peak flux      CPL   4.98e-01  7.66e-01  6.75e-01  4.11e-01  2.19e+00  2.35e+00   ph/cm2/s
      90%_error_low -2.09e-01 -1.53e-01 -1.31e-01 -2.43e-01 -3.74e-01 -4.62e-01   ph/cm2/s
      90%_error_hi   2.34e-01  1.59e-01  1.35e-01  5.50e-01  3.76e-01  6.62e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  245.2222    58.1319   0.0074    45.7784  -152.6068         3.0612679     25.669 TRIG_01205319                 
 
Foreground time interval of the image:
  0.252  17.264 (delta_t =  17.012 [sec])
Background time interval of the image:
-239.376   0.252 (delta_t = 239.628 [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    0.252 sec. to   17.264 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.27724     ( -0.0945992   0.0955486 )
Norm@50keV  : 1.26752E-02    ( -0.000704192   0.00070336 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   41.72     using 59 bins.
 Reduced chi-squared = 0.73193
# Null hypothesis probability of 9.36e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 17.01 sec: 1.50604 ( -0.08971  0.08997 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.14292e-06 ( -1.24069e-07  1.24304e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.252 sec. to   17.264 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.888209     ( -0.378134   0.416189 )
Epeak [keV] : 162.298      ( -55.8615 1805.85 )
Norm@50keV  : 1.90098E-02    ( -0.00598626   0.00985355 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   38.67     using 59 bins.
 Reduced chi-squared = 0.690536
# Null hypothesis probability of 9.63e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 17.01 sec: 1.47977 ( -0.09323  0.09348 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.11035e-06 ( -1.29757e-07  1.29223e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    7.636 sec. to    8.636 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.25692     ( -0.240893   0.248183 )
Norm@50keV  : 1.89766E-02    ( -0.00290896   0.00290174 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   47.21     using 59 bins.
 Reduced chi-squared = 0.828246
# Null hypothesis probability of 8.19e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.24699 ( -0.36542  0.36753 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.89596e-07 ( -2.98574e-08  2.99118e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    7.636 sec. to    8.636 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.348376     ( -1.00171   1.47532 )
Epeak [keV] : 102.234      ( -102.234 -102.234 )
Norm@50keV  : 4.95795E-02    ( -0.0495796   0.175344 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   45.22     using 59 bins.
 Reduced chi-squared = 0.8075
# Null hypothesis probability of 8.48e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 2.18744 ( -0.37376  0.37569 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.8482e-07 ( -3.17077e-08  3.11234e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 15.24 sec.
Hardness ratio (energy fluence ratio) = 1.65036500862

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

S(15-50 keV)  = 6.943761e-07
S(50-150 keV) = 1.448544e-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 = -9.123296062587759E-01, IMY = 4.727695310907867E-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:
-239.376000 0.252000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
149.6276  27.4243    3.1  32.2   77.4   2.9041   3.8 ------	UNKNOWN                       
185.7151  12.0491    2.8  21.5   -9.6   1.5196   4.1 ------	UNKNOWN                       

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

Time interval of the image:
0.252000 17.264000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
126.6530  72.5296    2.4  49.3  148.3   1.1498   4.9 ------	UNKNOWN                       
245.2222  58.1319    0.4  45.8 -152.6   3.0611  25.6 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
126.124610 962.695700
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.4576  35.3424  108.5  23.6  -78.4   0.1406   0.1    0.0	Her X-1                       
299.5716  35.2236    1.4  42.2 -140.7  17.2011   8.5    1.6	Cyg X-1                       
308.1447  41.0549    3.1  42.4 -153.9   7.1467   3.8    6.3	Cyg X-3                       
326.2854  38.2895    4.8  53.9 -165.3  -7.9303  -2.4    5.7	Cyg X-2                       
172.9260  67.3621    3.0  32.2   77.5   9.6128   3.9 ------	UNKNOWN                       
293.4868  85.8685    2.1  29.3  127.2   9.0592   5.4 ------	UNKNOWN                       
240.0722  70.9455    2.4  13.0  113.6   5.5726   4.8 ------	UNKNOWN                       
203.8846  24.4512    2.4  44.5   -0.3  10.0829   4.9 ------	UNKNOWN