Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Mon Jan 20 11:09:18 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger271019
======================================================================

  Trigger: 00271019      Segment: 000

  BAT Trigger Time: 195895737.92   [s; MET]
      Trigger Stop: 195895738.432   [s; MET]
               UTC: 2007-03-18T07:28:56.088640    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 48.5402261665742   Dec: -42.961988565526  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    10.03
     Image Trigger?:     NO
     Rate S/N Ratio:     17.9443584449264  [ if not an image trigger ]
     Image S/N Ratio:    10.03

  Analysis Position:   [ source = BAT ]
    RA: 48.5402261665742   Dec: -42.961988565526  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 48.4858797791712   Dec: -42.942277109951  [deg; J2000]  
        { 03h 13m 56.6s , -42d 56' 32.2" }
         +/- 0.76802989802986 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.229677613305789 [arcmin] (formal 1-sigma fit error)
    SNR: 44.3469660422778
 
  Angular difference between the analysis and refined position is 2.663609 arcmin
 
  Partial Coding Fraction: 0.8046875    [ including projection effects ]

  Duration
     T90: 130.368000030518 +/- 28.8086031720255
        Measured from: 0.719999998807907
                   to: 131.088000029325     [s; relative to TRIGTIME]
     T50: 35.0720000267029 +/- 4.93464486631663
        Measured from: 5.32800000905991
                   to: 40.4000000357628     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.21200001239777     
                   to: 2.21200001239777     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.00799998641014     
                   to: 171.536000013351     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.015939   1.533896   1.198511   0.375500
           0.060796   0.063851   0.057449   0.052009 [error]
 Peak      0.045642   0.073220   0.064797   0.018952
           0.005715   0.006430   0.005927   0.004918 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  172.544   -1.008  171.536
T90   130.368    0.720  131.088
T50    35.072    5.328   40.400
Peak    1.000    1.212    2.212
 
 
====== 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      -1.376    -0.088      0.088       -           -               -         1.56e-03     -7.45e-05          7.44e-05      43.940   57
CPL     -1.257    -0.163      0.336      330.081    -330.081      -330.081      1.78e-03     -2.82e-04          7.77e-04      43.540   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      -1.325     -0.158     0.158       -           -               -         1.34e-02     -1.26e-03          1.26e-03      64.720   57
CPL     -0.806     -0.576     0.682      118.368     -41.493      -118.368      2.42e-02     -1.13e-02          2.71e-02      62.490   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   3.07e-07  6.08e-07  9.37e-07  3.17e-06  2.62e-06  5.02e-06   erg/cm2
      90%_error_low -2.72e-08 -3.19e-08 -5.73e-08 -4.15e-07 -1.39e-07 -4.55e-07   erg/cm2
      90%_error_hi   2.80e-08  3.17e-08  5.71e-08  4.58e-07  1.40e-07  4.91e-07   erg/cm2
Peak flux       PL   4.66e-01  5.21e-01  4.16e-01  5.50e-01  1.61e+00  1.95e+00   ph/cm2/s
      90%_error_low -7.37e-02 -5.26e-02 -4.84e-02 -1.21e-01 -1.50e-01 -1.91e-01   ph/cm2/s
      90%_error_hi   7.71e-02  5.22e-02  4.80e-02  1.40e-01  1.50e-01  1.94e-01   ph/cm2/s
 
Fluence        CPL   2.99e-07  6.14e-07  9.45e-07  2.64e-06  2.60e-06  4.50e-06   erg/cm2
      90%_error_low -3.31e-08 -3.53e-08 -6.09e-08 -9.89e-07 -1.55e-07 -9.94e-07   erg/cm2
      90%_error_hi   2.80e-08  3.59e-08  6.19e-08  1.07e-06  1.54e-07  6.71e-07   erg/cm2
Peak flux      CPL   4.23e-01  5.46e-01  4.36e-01  3.15e-01  1.57e+00  1.72e+00   ph/cm2/s
      90%_error_low -8.87e-02 -6.07e-02 -5.48e-02 -1.44e-01 -7.77e-02 -2.18e-01   ph/cm2/s
      90%_error_hi   9.10e-02  6.25e-02  5.62e-02  2.81e-01  1.54e-01  3.11e-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
   48.4859   -42.9423   0.0043    21.5540   -57.2923         1.8327941     44.347 TRIG_00271019                 
 
Foreground time interval of the image:
 -1.008   9.981 (delta_t =  10.989 [sec])
Background time interval of the image:
-113.419  -1.008 (delta_t = 112.411 [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   -1.008 sec. to  171.536 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.37558     ( -0.088271   0.0883 )
Norm@50keV  : 1.56413E-03    ( -7.44954e-05   7.43979e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.94 using 59 PHA bins.
# Reduced chi-squared =         0.7709 for     57 degrees of freedom 
# Null hypothesis probability =   8.975208e-01
 
Photon flux (15-150 keV)    in 172.5 sec: 0.189456 ( -0.009282  0.009303 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.62078e-06 ( -1.39305e-07  1.40115e-07 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -1.008 sec. to  171.536 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.25748     ( -0.162714   0.336405 )
Epeak [keV] : 330.081      ( -330.082 -330.082 )
Norm@50keV  : 1.78299E-03    ( -0.000281593   0.00077667 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.54 using 59 PHA bins.
# Reduced chi-squared =         0.7775 for     56 degrees of freedom 
# Null hypothesis probability =   8.875840e-01
 
Photon flux (15-150 keV)    in 172.5 sec: 0.188131 ( -0.009912  0.009909 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.59597e-06 ( -1.54738e-07  1.53944e-07 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from    1.212 sec. to    2.212 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.32538     ( -0.158419   0.157659 )
Norm@50keV  : 1.33950E-02    ( -0.00126467   0.00126086 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.72 using 59 PHA bins.
# Reduced chi-squared =          1.135 for     57 degrees of freedom 
# Null hypothesis probability =   2.252440e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.60579 ( -0.15022  0.15031 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.31583e-07 ( -1.405e-08  1.41843e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    1.212 sec. to    2.212 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.806379     ( -0.575782   0.682046 )
Epeak [keV] : 118.368      ( -41.4931 -118.368 )
Norm@50keV  : 2.42270E-02    ( -0.011324   0.0271302 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.49 using 59 PHA bins.
# Reduced chi-squared =          1.116 for     56 degrees of freedom 
# Null hypothesis probability =   2.566618e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.57472 ( -0.07767  0.15448 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.27022e-07 ( -1.50834e-08  1.51585e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 130.368 sec.
Hardness ratio (energy fluence ratio) = 1.54162957403

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

    S(15-50 keV)  = 9.146828e-07
S(50-150 keV) = 1.706109e-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 = 2.134392873802190E-01, IMY = 3.323675962069452E-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:
-113.419380 -1.008000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.3156 -60.7611    8.7  44.6  130.4   0.6340   1.3    8.3	Cen X-3                       
186.2891 -62.7078    5.6  48.3  139.9   1.0123   2.0   10.8	GX 301-2                      
 75.1735 -39.8467    2.3  19.5    2.3   0.5000   4.9 ------	UNKNOWN                       
 66.2951  -5.3186    2.3  54.1  -12.6   1.4965   5.1 ------	UNKNOWN                       
285.8080 -58.6388    2.7  59.1 -166.2   2.9200   4.3 ------	UNKNOWN                       
320.8343 -53.8954    5.2  54.0 -143.2   1.3839   2.2 ------	UNKNOWN                       
 41.9337 -13.4994    3.1  50.7  -44.5   2.0728   3.7 ------	UNKNOWN

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

    Time interval of the image:
-1.008000 9.980600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.3036 -60.6292   53.7  44.7  130.2  -0.0350  -0.2    0.5	Cen X-3                       
186.6820 -62.8931   10.5  48.3  140.2  -0.1811  -1.1    7.4	GX 301-2                      
113.7662 -63.5245    2.3  20.3  113.9   0.2189   5.1 ------	UNKNOWN                       
238.0174 -66.2490    2.6  54.1  167.1   0.7638   4.5 ------	UNKNOWN                       
 79.4073 -25.3595    2.3  34.3    6.6   0.2355   5.0 ------	UNKNOWN                       
 48.4859 -42.9423    0.3  21.6  -57.3   1.8327  44.4 ------	UNKNOWN                       
297.6359 -55.8728    1.9  59.2 -158.1   1.4249   6.1 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
52.780600 962.163000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
312.7394 -54.8767    3.8  59.0 -166.2   9.6607   3.1 ------	UNKNOWN                       
 44.1302   2.4307    3.0  45.6  -34.3   3.0425   3.8 ------	UNKNOWN                       
 44.4027  11.4008    5.1  54.5  -33.1   5.4171   2.3 ------	UNKNOWN                       
 35.8270   6.3838    3.1  50.7  -44.5   9.5670   3.7 ------	UNKNOWN