GRB150202A: 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 v2.46
    Process Start Time: Tue Feb 17 21:28:04 EST 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger629547
======================================================================

  Trigger: 00629547      Segment: 000

  BAT Trigger Time: 444611415.488   [s; MET]
      Trigger Stop: 444611417.536   [s; MET]
               UTC: 2015-02-02T23:10:02.353060    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 39.2357037817736   Dec: -33.1499202499856  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    10.85
     Image Trigger?:     NO
     Rate S/N Ratio:     18.6815416922694  [ if not an image trigger ]
     Image S/N Ratio:    10.85

  Analysis Position:   [ source = BAT ]
    RA: 39.2357037817736   Dec: -33.1499202499856  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 39.243669948438   Dec: -33.1331291710513  [deg; J2000]  
        { 02h 36m 58.5s , -33d 07' 59.3" }
         +/- 1.61349123068584 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.718884860842111 [arcmin] (formal 1-sigma fit error)
    SNR: 15.3570903038171
 
  Angular difference between the analysis and refined position is 1.084047 arcmin
 
  Partial Coding Fraction: 0.6015625    [ including projection effects ]

  Duration
     T90: 25.472000002861 +/- 4.82001162478996
        Measured from: -0.767999947071075
                   to: 24.7040000557899     [s; relative to TRIGTIME]
     T50: 16.1919999718666 +/- 1.38453165221894
        Measured from: 1.34400004148483
                   to: 17.5360000133514     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 17.3240000009537     
                   to: 18.3240000009537     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -1.59999996423721     
                   to: 26.688000023365     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.327787   0.312433   0.300886   0.126350
           0.033837   0.034922   0.031059   0.026605 [error]
 Peak      0.026404   0.037940   0.045804   0.016577
           0.006616   0.006929   0.006324   0.005304 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   28.288   -1.600   26.688
T90    25.472   -0.768   24.704
T50    16.192    1.344   17.536
Peak    1.000   17.324   18.324
 
 
====== 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      -1.466    -0.194      0.192       -           -               -         2.31e-03     -2.44e-04          2.42e-04      59.440   57
CPL     -1.470    -0.694      0.365     9999.350      N/A           N/A         2.32e-03        N/A               N/A         59.460   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      -1.127     -0.293     0.303       -           -               -         8.50e-03     -1.32e-03          1.32e-03      36.300   57
CPL     -1.130     -0.287     0.313     9999.350    -9999.350      -9999.350      8.52e-03     -1.31e-03          1.03e-02      36.310   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   8.09e-08  1.52e-07  2.20e-07  6.76e-07  6.24e-07  1.13e-06   erg/cm2
      90%_error_low -1.44e-08 -1.64e-08 -3.11e-08 -1.89e-07 -7.35e-08 -2.15e-07   erg/cm2
      90%_error_hi   1.51e-08  1.62e-08  3.08e-08  2.35e-07  7.44e-08  2.53e-07   erg/cm2
Peak flux       PL   2.45e-01  3.08e-01  2.82e-01  4.51e-01  9.89e-01  1.29e+00   ph/cm2/s
      90%_error_low -7.62e-02 -6.07e-02 -5.10e-02 -1.58e-01 -1.59e-01 -2.13e-01   ph/cm2/s
      90%_error_hi   8.50e-02  5.87e-02  4.98e-02  2.09e-01  1.60e-01  2.22e-01   ph/cm2/s
 
Fluence        CPL   8.09e-08  1.49e-07  2.17e-07  7.52e-07  6.29e-07  1.09e-06   erg/cm2
      90%_error_low -1.45e-08    N/A    -2.85e-08 -3.87e-07 -7.86e-08 -2.85e-07   erg/cm2
      90%_error_hi   1.51e-08    N/A     3.34e-08  8.32e-08  6.93e-08  2.45e-07   erg/cm2
Peak flux      CPL   2.45e-01  3.06e-01  2.81e-01  4.48e-01  9.97e-01  1.33e+00   ph/cm2/s
      90%_error_low     N/A   -7.17e-02     N/A       N/A       N/A   -3.05e-01   ph/cm2/s
      90%_error_hi      N/A    7.28e-02     N/A       N/A       N/A    2.05e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   39.2437   -33.1331   0.0124    22.7315    80.1288         1.0887588     15.357 TRIG_00629547                 
 
Foreground time interval of the image:
 -1.600  26.688 (delta_t =  28.288 [sec])
Background time interval of the image:
-239.488  -1.600 (delta_t = 237.888 [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   -1.600 sec. to   26.688 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.46596     ( -0.193657   0.192164 )
Norm@50keV  : 2.31171E-03    ( -0.000243852   0.000241735 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.44 using 59 PHA bins.
# Reduced chi-squared =          1.043 for     57 degrees of freedom 
# Null hypothesis probability =   3.869044e-01
 
Photon flux (15-150 keV)    in 28.29 sec: 0.286038 ( -0.029558  0.02962 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.24083e-07 ( -7.35124e-08  7.43631e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -1.600 sec. to   26.688 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.12082     ( -0.0430359   1.01626 )
Epeak [keV] : 45.8541      (   )
Norm@50keV  : 1.04518E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.42 using 59 PHA bins.
# Reduced chi-squared =          1.061 for     56 degrees of freedom 
# Null hypothesis probability =   3.521629e-01
 
Photon flux (15-150 keV)    in 28.29 sec: 0.286005 ( -0.02958  0.029605 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.28918e-07 ( -7.86009e-08  6.92873e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   17.324 sec. to   18.324 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.12669     ( -0.293238   0.303057 )
Norm@50keV  : 8.49883E-03    ( -0.00132454   0.00132269 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          36.30 using 59 PHA bins.
# Reduced chi-squared =         0.6368 for     57 degrees of freedom 
# Null hypothesis probability =   9.852219e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.988513 ( -0.159235  0.159747 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.81252e-08 ( -1.52516e-08  1.54033e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   17.324 sec. to   18.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.12955     ( -0.288052   0.312678 )
Epeak [keV] : 9999.35      ( -9999.36 -9999.36 )
Norm@50keV  : 8.52336E-03    ( -0.0013262   0.0102838 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          36.31 using 59 PHA bins.
# Reduced chi-squared =         0.6484 for     56 degrees of freedom 
# Null hypothesis probability =   9.809078e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.997393 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.85605e-08 ( -1.88369e-08  1.81409e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 25.472 sec.
Hardness ratio (energy fluence ratio) = 1.44800434912

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

S(15-50 keV)  = 2.3263905e-07
S(50-150 keV) = 3.914588e-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 = 7.182336479167151E-02, IMY = -4.127527821486207E-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:
-239.488000 -1.600000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 26.9186  16.4695    3.0  55.9   10.6   3.8602   3.9 ------	UNKNOWN                       
 28.5016 -27.3399    2.5  17.4   51.9   0.8142   4.6 ------	UNKNOWN                       
344.1786 -84.3851    3.0  47.5  176.6   1.4708   3.8 ------	UNKNOWN                       
308.4789 -77.6262    2.4  47.8 -172.0   1.5870   4.8 ------	UNKNOWN                       

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

Time interval of the image:
-1.600000 26.688000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 81.0199 -65.1211    2.4  47.8  141.0   1.0930   4.8 ------	UNKNOWN                       
 39.2437 -33.1331    0.7  22.7   80.1   1.0889  15.4 ------	UNKNOWN                       
348.4809 -57.4130    2.6  25.1 -156.7   0.2391   4.5 ------	UNKNOWN                       
327.8250 -22.0697    2.2  40.7  -87.3   1.0825   5.4 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
72.412610 962.570600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 91.5591 -67.9235    2.8  45.7  166.1   4.8800   4.1 ------	UNKNOWN                       
124.5196 -75.9087    4.7  56.8  173.8   7.4694   2.5 ------	UNKNOWN                       
 23.4294  -8.2688    2.8  28.8  -23.2   2.1959   4.0 ------	UNKNOWN                       
340.9737 -51.5341    3.3  45.4 -121.3   8.8256   3.5 ------	UNKNOWN