Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.47
    Process Start Time: Mon May 18 14:43:00 EDT 2020
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger957271
======================================================================

  Trigger: 00957271      Segment: 000

  BAT Trigger Time: 603790633.6   [s; MET]
      Trigger Stop: 603790633.856   [s; MET]
               UTC: 2020-02-19T07:36:49.139100    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 342.644409036627   Dec: -59.1083992201985  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    13.23
     Image Trigger?:     NO
     Rate S/N Ratio:     97.4320275884681  [ if not an image trigger ]
     Image S/N Ratio:    13.23

  Analysis Position:   [ source = BAT ]
    RA: 342.644409036627   Dec: -59.1083992201985  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 342.594694865084   Dec: -59.1012457317369  [deg; J2000]  
        { 22h 50m 22.7s , -59d 06' 04.5" }
         +/- 2.3689526956136 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.07910232751214 [arcmin] (formal 1-sigma fit error)
    SNR: 8.8723328216173
 
  Angular difference between the analysis and refined position is 1.590605 arcmin
 
  Partial Coding Fraction: 0.9921875    [ including projection effects ]

  Duration
     T90: 288 +/- 50.5964425626941
        Measured from: -15.6000000238419
                   to: 272.399999976158     [s; relative to TRIGTIME]
     T50: 144 +/- 50.5964425626941
        Measured from: 0.399999976158142
                   to: 144.399999976158     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -8.10000002384186     
                   to: -7.10000002384186     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -15.6000000238419     
                   to: 304.399999976158     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.481958   0.818164   0.553697   0.172386
           0.101575   0.103531   0.089510   0.078650 [error]
 Peak     -0.004904   0.006953  -0.005834   0.000983
           0.005995   0.005853   0.005085   0.004551 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  320.000  -15.600  304.400
T90   288.000  -15.600  272.400
T50   144.000    0.400  144.400
Peak    1.000   -8.100   -7.100
 
 
====== 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      -1.444    -0.255      0.252       -           -               -         4.11e-04     -6.11e-05          6.06e-05      59.820   57
CPL     -0.796    -0.923      1.516       92.272     -35.404       -92.272      8.75e-04     -5.12e-04          4.09e-03      58.890   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      -1.500      1.500     1.500       -           -               -         0.00e+00     0.00e+00          8.04e-04      73.520   57
CPL     -1.000      1.000     1.000       80.000     -80.000       -80.000      0.00e+00        N/A               N/A         73.520   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   1.59e-07  3.03e-07  4.45e-07  1.40e-06  1.26e-06  2.31e-06   erg/cm2
      90%_error_low -3.78e-08 -4.60e-08 -8.58e-08 -5.00e-07 -2.06e-07 -5.80e-07   erg/cm2
      90%_error_hi   4.02e-08  4.55e-08  8.51e-08  6.61e-07  2.10e-07  7.13e-07   erg/cm2
Peak flux       PL   3.62e-10  5.82e-10  8.99e-08  1.70e-05  4.47e-09  3.91e-06   ph/cm2/s
      90%_error_low -3.62e-10 -5.82e-10 -8.99e-08 -1.70e-05 -4.47e-09 -3.91e-06   ph/cm2/s
      90%_error_hi   5.31e-02  3.41e-02  2.72e-02  3.66e-01  1.02e-01  3.79e-01   ph/cm2/s
 
Fluence        CPL   1.43e-07  3.23e-07  4.61e-07  5.68e-07  1.19e-06  1.50e-06   erg/cm2
      90%_error_low -4.84e-08 -5.76e-08 -9.34e-08 -4.30e-07 -2.36e-07 -4.95e-07   erg/cm2
      90%_error_hi   4.89e-08  6.16e-08  9.58e-08  9.98e-07  2.38e-07  1.26e-06   erg/cm2
Peak flux      CPL   1.87e-02  4.71e-02  7.16e-04  4.03e-09  5.96e-02  6.17e-02   ph/cm2/s
      90%_error_low -1.87e-02 -4.71e-02 -7.16e-04     N/A   -5.96e-02 -6.17e-02   ph/cm2/s
      90%_error_hi   5.67e-02  6.16e-02  2.46e-02     N/A    1.06e-01  1.04e-01   ph/cm2/s
 
======================================================================
  • Special notes of this burst




    Image

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

    #   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
      342.5947   -59.1012   0.0218    17.4796    -0.9238         0.5972333      8.872 TRIG_00957271                 
     
    Foreground time interval of the image:
    -15.600  15.501 (delta_t =  31.101 [sec])
    Background time interval of the image:
    -116.099 -15.600 (delta_t = 100.499 [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

    Bokeh Plot

    Other quick-look light curves:




    Spectra

    Notes:

    Time averaged spectrum fit using the average DRM

    Power-law model
    Time interval is from  -15.600 sec. to  304.400 sec.
    XSPEC12>exit
     XSPEC: quit
     
     
    Photon index: -1.44423     ( -0.254625   0.251554 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 1.44423     ( -0.251554   0.254625 )
    Norm@50keV  : 4.10939E-04    ( -6.1078e-05   6.06002e-05 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 320 sec: 5.05716E-02 ( -0.0073815  0.0073931 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.25988e-06 ( -2.06465e-07  2.09721e-07 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from  -15.600 sec. to  304.400 sec.
     XSPEC: quit
     
     
    Photon index: -0.795898     ( -0.923494   1.51618 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.795898     ( -1.51618   0.923494 )
    Epeak [keV] : 92.2716      ( -35.3773 -92.2445 )
    Norm@50keV  : 8.74891E-04    ( -0.000512772   0.00408932 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 320 sec: 4.90771E-02 ( -0.007987  0.0078622 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.19498e-06 ( -2.36329e-07  2.38165e-07 ) ergs/cm2
     
    

    1-s peak spectrum fit

    Power-law model
    Time interval is from   -8.100 sec. to   -7.100 sec.
    XSPEC12>exit
     XSPEC: quit
     
     
    Photon index: -1.5     ( 1.5   1.5 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 1.50000     ( -1.5   -1.5 )
    Norm@50keV  : 0.0    ( 0   0.000803549 )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 1 sec: 4.47484E-09 ( -4.47484e-09  0.10162 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.00231e-30 ( 1  8.78658e-09 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from   -8.100 sec. to   -7.100 sec.
     XSPEC: quit
     
     
    Photon index: -1     ( 1   1 )
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 1.00000     ( -1   -1 )
    Epeak [keV] : 80.0000      ( -80 -80 )
    Norm@50keV  : 0.0    (     )
    ------------------------------------------------------------
     
    Photon flux (15-150 keV)    in 1 sec: 5.95983E-02 ( -0.0595983  0.106183 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 1.0074e-30 ( 1  7.97793e-09 ) ergs/cm2
     
    

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot

    T90                                   = 288.0 sec.
    Hardness ratio (energy fluence ratio) = 1.46997522427
    

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

    S(15-50 keV)  = 4.62362e-07
    S(50-150 keV) = 7.975111e-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 = 3.148667134259973E-01, IMY = 5.077342664083662E-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:
    -116.099370 -15.600000
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    255.9839 -37.8465    1.2  39.8  160.5   2.4722   9.7    0.2	4U 1700-377                   
    256.5427 -36.3191    7.0  40.6  162.7   0.4390   1.7    8.1	GX 349+2                      
    263.1956 -24.8126    0.0  46.0  179.7  -0.0159  -0.1   10.9	GX 1+4                        
    264.6734 -44.5274   11.8  30.5  159.6   0.1735   1.0    5.5	4U 1735-44                    
    270.4072 -25.1816  338.2  42.2 -172.7  -0.0075  -0.0    9.1	GX 5-1                        
    270.3988 -25.7777    5.3  41.7 -173.2   0.4648   2.2    5.6	GRS 1758-258                  
    273.9916 -14.0713    4.7  50.4 -161.3   0.8903   2.4    2.3	GX 17+2                       
    276.0750 -30.4165    4.1  35.1 -170.4   0.4569   2.8    8.3	H1820-303                     
    284.9486 -24.7951    9.8  36.4 -153.9  -0.1979  -1.2    8.9	HT1900.1-2455                 
    263.0852 -33.7369    3.6  39.0  171.6  -0.6735  -3.2    7.6	GX 354-0                      
     18.1480 -80.1137    2.5  31.2   48.5   0.8795   4.5 ------	UNKNOWN                       
    333.7285 -46.6250    2.7  17.6  -47.0   0.5455   4.3 ------	UNKNOWN                       
    264.4000 -12.0755    2.5  56.4 -170.6   2.8563   4.7 ------	UNKNOWN                       
    295.1485  -7.9692    2.6  49.7 -133.0   3.0398   4.5 ------	UNKNOWN                       
    

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

    Time interval of the image:
    -15.600000 15.500590
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    255.8468 -37.7380    9.2  40.0  160.5   0.1501   1.2    9.2	4U 1700-377                   
    256.5041 -36.5610    5.4  40.4  162.4   0.2606   2.1    8.9	GX 349+2                      
    262.9388 -24.6819    5.3  46.3  179.5  -0.3300  -2.2    5.4	GX 1+4                        
    264.8801 -44.5201    8.1  30.4  159.8  -0.1210  -1.4    7.2	4U 1735-44                    
    270.1528 -25.1129   10.9  42.4 -173.0  -0.1148  -1.1    7.4	GX 5-1                        
    270.4376 -25.7112   22.4  41.7 -173.1  -0.0567  -0.5    7.5	GRS 1758-258                  
    274.1466 -14.0107    3.7  50.4 -161.1  -0.5591  -3.1    8.3	GX 17+2                       
    275.7169 -30.3239   94.4  35.3 -170.7   0.0117   0.1   11.1	H1820-303                     
    284.9016 -24.8373   36.2  36.3 -154.0   0.0303   0.3    8.9	HT1900.1-2455                 
    262.8258 -33.8324   36.4  39.0  171.2   0.0344   0.3    8.1	GX 354-0                      
     46.2839 -54.2479    2.2  50.2   17.3   1.0545   5.2 ------	UNKNOWN                       
    342.5943 -59.1018    1.3  17.5   -0.9   0.5988   8.9 ------	UNKNOWN                       
    357.6837 -21.8645    2.2  49.0  -48.1   1.5445   5.2 ------	UNKNOWN                       
    

    Post-slew image of 15-350 keV band

    Time interval of the image:
    56.700590 962.448000
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    255.9485 -37.8477    3.3  56.6  174.7  11.3776   3.5    1.8	4U 1700-377                   
    264.9785 -44.5042    0.0  47.2  175.7   2.7241   1.7   10.6	4U 1735-44                    
    276.1613 -30.3641    0.0  52.4 -163.5  -1.2591  -0.7   12.2	H1820-303                     
    285.0631 -24.9402    5.0  52.3 -151.4   4.6301   2.3    1.9	HT1900.1-2455                 
    262.9451 -33.9184    4.8  56.3 -177.1  -7.5956  -2.4    5.5	GX 354-0                      
    255.2001 -38.1348    2.3  56.8  173.9  16.1175   5.1 ------	UNKNOWN                       
    279.6192 -51.7113    3.7  35.1  177.6   2.8342   3.2 ------	UNKNOWN                       
    264.0837 -32.5222    2.7  56.8 -175.2  12.4080   4.3 ------	UNKNOWN                       
    299.0252 -28.8309    3.2  42.3 -139.9   4.2953   3.6 ------	UNKNOWN                       
    303.3843 -20.1779    2.3  48.0 -129.1  14.2438   5.0 ------	UNKNOWN