GRB240411B: 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 15:35:14 EDT 2024
             Host Name: batproc1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1221183
======================================================================

  Trigger: 01221183      Segment: 000

  BAT Trigger Time: 734542407.104   [s; MET]
      Trigger Stop: 734542409.152   [s; MET]
               UTC: 2024-04-11T15:32:53.852800    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 231.561347866817   Dec: -2.15328247773132  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.94
     Image Trigger?:     NO
     Rate S/N Ratio:     11.3578166916005  [ if not an image trigger ]
     Image S/N Ratio:    7.94

  Analysis Position:   [ source = BAT ]
    RA: 231.561347866817   Dec: -2.15328247773132  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 231.562744335981   Dec: -2.17330455475162  [deg; J2000]  
        { 15h 26m 15.1s , -02d 10' 23.9" }
         +/- 3.64153683129493 [arcmin] (estimated 90% radius based on SNR)
         +/- 2.49761370978574 [arcmin] (formal 1-sigma fit error)
    SNR: 4.80046253346946
 
  Angular difference between the analysis and refined position is 1.204239 arcmin
 
  Partial Coding Fraction: 0.53125    [ including projection effects ]

  Duration
     T90: 33.2640000581741 +/- 1.44222047183285
        Measured from: 0.287999987602234
                   to: 33.5520000457764     [s; relative to TRIGTIME]
     T50: 29.824000120163 +/- 21.1709505863068
        Measured from: 1.58399999141693
                   to: 31.4080001115799     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 32.8680000305176     
                   to: 33.8680000305176     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.368000030517578     
                   to: 33.9200000762939     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.224902   0.322142   0.183404   0.127799
           0.060563   0.062961   0.053051   0.045138 [error]
 Peak      0.035573   0.041587   0.036791   0.011644
           0.011978   0.011664   0.010331   0.007827 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   34.288   -0.368   33.920
T90    33.264    0.288   33.552
T50    29.824    1.584   31.408
Peak    1.000   32.868   33.868
 
 
====== 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      -1.675    -0.427      0.417       -           -               -         1.53e-03     -3.77e-04          3.63e-04      41.500   57
CPL     -1.695    -0.410      0.522     9999.360    -9999.350      -9999.360      1.52e-03     -3.61e-04          3.28e-03      41.520   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      -1.603     -0.499     0.494       -           -               -         7.40e-03     -2.27e-03          2.24e-03      57.760   57
CPL     -0.688     -1.544     3.162       68.115     -68.115       -68.115      2.26e-02     -2.26e-02          1.12e+00      57.170   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   7.91e-08  1.31e-07  1.64e-07  4.07e-07  4.88e-07  7.81e-07   erg/cm2
      90%_error_low -2.85e-08 -3.02e-08 -5.30e-08 -2.20e-07 -1.23e-07 -2.78e-07   erg/cm2
      90%_error_hi   3.03e-08  2.98e-08  5.24e-08  3.53e-07  1.25e-07  3.80e-07   erg/cm2
Peak flux       PL   3.36e-01  3.18e-01  2.10e-01  2.14e-01  9.52e-01  1.08e+00   ph/cm2/s
      90%_error_low -1.55e-01 -1.04e-01 -7.71e-02 -1.23e-01 -2.95e-01 -3.22e-01   ph/cm2/s
      90%_error_hi   1.77e-01  1.01e-01  7.60e-02  1.90e-01  2.98e-01  3.22e-01   ph/cm2/s
 
Fluence        CPL   7.15e-08  1.00e-07  1.08e-07  2.66e-07  3.50e-07  5.44e-07   erg/cm2
      90%_error_low -4.06e-08 -5.36e-08 -5.36e-08 -1.39e-07 -1.79e-07 -2.88e-07   erg/cm2
      90%_error_hi   3.76e-08  3.29e-08  2.70e-08  8.90e-08  9.50e-08  2.13e-07   erg/cm2
Peak flux      CPL   2.95e-01  3.52e-01  2.22e-01  8.34e-02  9.27e-01  9.52e-01   ph/cm2/s
      90%_error_low -1.77e-01 -1.25e-01 -1.39e-01 -8.34e-02 -3.01e-01 -3.21e-01   ph/cm2/s
      90%_error_hi   1.98e-01  1.39e-01  9.24e-02  1.84e-01  3.03e-01  3.78e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  231.5627    -2.1733   0.0400    40.1461     0.0783         0.5030698      4.800 TRIG_01221183                 
 
Foreground time interval of the image:
 -0.368  27.397 (delta_t =  27.765 [sec])
Background time interval of the image:
-114.603  -0.368 (delta_t = 114.235 [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   -0.368 sec. to   33.920 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.67542     ( -0.427243   0.417198 )
Norm@50keV  : 1.53227E-03    ( -0.000376666   0.000363158 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   41.50     using 59 bins.
 Reduced chi-squared = 0.72807
# Null hypothesis probability of 9.39e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 34.29 sec: 0.201794 ( -0.04627  0.046391 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.87549e-07 ( -1.23158e-07  1.25193e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.368 sec. to   33.920 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.69492     ( -0.414632   0.516787 )
Epeak [keV] : 9999.36      ( -9999.35 -9999.36 )
Norm@50keV  : 1.51642E-03    ( -0.000373949   0.00326873 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   41.52     using 59 bins.
 Reduced chi-squared = 0.741429
# Null hypothesis probability of 9.26e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 34.29 sec: 0.202286 ( -0.047357  0.046409 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.50331e-07 ( -1.78972e-07  9.50152e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   32.868 sec. to   33.868 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.60287     ( -0.498937   0.493998 )
Norm@50keV  : 7.40114E-03    ( -0.00226659   0.00224491 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   57.76     using 59 bins.
 Reduced chi-squared = 1.01333
# Null hypothesis probability of 4.47e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 0.951976 ( -0.295299  0.297704 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.92006e-08 ( -2.19464e-08  2.22886e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   32.868 sec. to   33.868 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.687966     ( -1.54355   3.16176 )
Epeak [keV] : 68.1151      ( -68.1137 -68.1137 )
Norm@50keV  : 2.26059E-02    ( -0.0226071   1.12428 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   57.17     using 59 bins.
 Reduced chi-squared = 1.02089
# Null hypothesis probability of 4.31e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 1 sec: 0.927039 ( -0.300572  0.303051 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.50609e-08 ( -2.36228e-08  2.41936e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 33.264 sec.
Hardness ratio (energy fluence ratio) = 1.25233366557

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

S(15-50 keV)  = 2.0974433e-07
S(50-150 keV) = 2.778024e-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 = 8.434542707590268E-01, IMY = -1.152957767770145E-03

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:
-114.603400 -0.368000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
195.5788 -29.5613    3.0  32.1   77.5   1.7356   3.9 ------	UNKNOWN                       
200.7481 -16.2291    3.1  20.6   58.4   0.9483   3.8 ------	UNKNOWN                       
239.2581 -13.3309    2.1  49.7   13.6   2.9552   5.4 ------	UNKNOWN                       
242.4405  10.0951    2.5  51.0  -17.2   2.4280   4.6 ------	UNKNOWN                       
220.7686  17.4338    2.5  32.3  -35.8   1.2241   4.6 ------	UNKNOWN                       
166.6011  40.3002    2.1  44.2 -123.6   4.3618   5.4 ------	UNKNOWN                       
158.9416  40.4358    2.3  48.2 -129.5   5.5212   5.0 ------	UNKNOWN                       

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

Time interval of the image:
-0.368000 27.396590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']

Post-slew image of 15-350 keV band

Time interval of the image:
158.596600 562.196600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9744 -15.6256    0.8  18.9  -30.4  11.4755  14.9    0.9	Sco X-1                       
254.3602  35.3113   36.6  43.1 -139.1  -0.4879  -0.3    5.1	Her X-1                       
256.0642 -37.8928    6.6  42.2  -15.8   2.0598   1.7    4.7	4U 1700-377                   
256.2600 -36.3588    8.5  41.1  -17.5   1.5766   1.4    9.3	GX 349+2                      
263.0097 -24.7863    5.2  37.8  -37.2   2.5368   2.2    2.4	GX 1+4                        
264.8672 -44.4022    5.8  51.5  -16.8  -3.8006  -2.0    6.0	4U 1735-44                    
268.3308  -1.4877    7.1  36.7  -77.1   2.6160   1.6    3.1	SW J1753.5-0127               
270.2034 -24.9679    7.2  43.7  -41.8   2.4013   1.6    8.0	GX 5-1                        
270.1981 -25.8951   19.1  44.1  -40.6   0.9406   0.6   10.7	GRS 1758-258                  
273.9887 -14.0585   34.7  43.6  -58.4  -1.0415  -0.3    1.7	GX 17+2                       
275.9124 -30.2678    5.8  50.5  -38.2   5.4560   2.0    6.0	H1820-303                     
262.9609 -33.9971    7.9  43.3  -25.8  -1.8815  -1.5    9.8	GX 354-0                      
201.8198 -15.2651    2.6  32.1   77.5   7.1460   4.4 ------	UNKNOWN                       
200.3989  23.0677    2.9  39.5  144.8   7.8024   3.9 ------	UNKNOWN                       
253.0844 -47.4406    2.4  49.0   -5.9   6.4088   4.7 ------	UNKNOWN