Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Sun Jan 12 05:06:49 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger550906
======================================================================

  Trigger: 00550906      Segment: 000

  BAT Trigger Time: 384883701.376   [s; MET]
      Trigger Stop: 384883701.504   [s; MET]
               UTC: 2013-03-13T16:08:11.057240    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 236.42303778442   Dec: -0.361783296507332  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.95
     Image Trigger?:     NO
     Rate S/N Ratio:     12.9228479833201  [ if not an image trigger ]
     Image S/N Ratio:    7.95

  Analysis Position:   [ source = BAT ]
    RA: 236.42303778442   Dec: -0.361783296507332  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 236.437591682223   Dec: -0.360699108529194  [deg; J2000]  
        { 15h 45m 45.0s , -00d 21' 38.5" }
         +/- 2.39180430748566 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.09537422327281 [arcmin] (formal 1-sigma fit error)
    SNR: 8.75148486701875
 
  Angular difference between the analysis and refined position is 0.875636 arcmin
 
  Partial Coding Fraction: 0.828125    [ including projection effects ]

  Duration
     T90: 0.171999931335449 +/- 0.0357770801763245
        Measured from: 0.0200000405311584
                   to: 0.191999971866608     [s; relative to TRIGTIME]
     T50: 0.0839999318122864 +/- 0.0393954323691675
        Measured from: 0.0440000295639038
                   to: 0.12799996137619     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.38400000333786     
                   to: 0.61599999666214     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.0120000243186951     
                   to: 0.216000020503998     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.015219   0.015743   0.015893   0.004812
           0.003270   0.003082   0.002879   0.002173 [error]
 Peak      0.015763   0.019607   0.018934   0.005267
           0.006515   0.005975   0.005202   0.004325 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.204    0.012    0.216
T90     0.172    0.020    0.192
T50     0.084    0.044    0.128
Peak    1.000   -0.384    0.616
 
 
====== 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      -1.508    -0.351      0.339       -           -               -         1.53e-02     -3.03e-03          2.98e-03      68.200   57
CPL     -1.355    -1.502      1.519      209.683    -209.683      -209.683      1.82e-02     -1.82e-02          8.33e-02      68.160   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      -1.282     -0.507     0.517       -           -               -         3.92e-03     -1.14e-03          1.14e-03      49.150   57
CPL      0.229     -1.879     4.383       81.674     -30.346       -81.674      1.88e-02     -1.88e-02          9.66e-01      47.930   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   4.00e-09  7.32e-09  1.03e-08  3.03e-08  2.95e-08  5.20e-08   erg/cm2
      90%_error_low -1.22e-09 -1.44e-09 -2.70e-09 -1.40e-08 -6.37e-09 -1.67e-08   erg/cm2
      90%_error_hi   1.33e-09  1.42e-09  2.67e-09  2.05e-08  6.50e-09  2.20e-08   erg/cm2
Peak flux       PL   1.31e-01  1.50e-01  1.24e-01  1.70e-01  4.67e-01  5.75e-01   ph/cm2/s
      90%_error_low -6.42e-02 -5.13e-02 -4.20e-02 -9.51e-02 -1.40e-01 -1.70e-01   ph/cm2/s
      90%_error_hi   7.79e-02  5.01e-02  4.12e-02  1.51e-01  1.41e-01  1.75e-01   ph/cm2/s
 
Fluence        CPL   3.74e-09  5.23e-09  5.66e-09  1.41e-08  1.83e-08  2.86e-08   erg/cm2
      90%_error_low -1.00e-09 -2.30e-09 -2.24e-09 -6.22e-09 -7.58e-09 -1.25e-08   erg/cm2
      90%_error_hi   5.60e-10  1.69e-09  1.37e-09  4.62e-09  4.81e-09  1.05e-08   erg/cm2
Peak flux      CPL   8.83e-02  1.59e-01  1.41e-01  5.63e-02  4.29e-01  4.45e-01   ph/cm2/s
      90%_error_low -7.41e-02 -6.49e-02 -5.09e-02 -5.63e-02 -1.52e-01 -1.66e-01   ph/cm2/s
      90%_error_hi   9.97e-02  6.09e-02  5.53e-02  1.60e-01  1.53e-01  2.29e-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
  236.4376    -0.3607   0.0219    20.8065   -50.5674         0.0474488      8.751 TRIG_00550906                 
 
Foreground time interval of the image:
  0.012   0.216 (delta_t =   0.204 [sec])
Background time interval of the image:
-239.376   0.012 (delta_t = 239.388 [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    0.012 sec. to    0.216 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.50836     ( -0.350597   0.338699 )
Norm@50keV  : 1.52537E-02    ( -0.0030302   0.00297764 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.20 using 59 PHA bins.
# Reduced chi-squared =          1.197 for     57 degrees of freedom 
# Null hypothesis probability =   1.470537e-01
 
Photon flux (15-150 keV)    in 0.204 sec: 1.90863 ( -0.36347  0.36439 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.94835e-08 ( -6.36711e-09  6.50221e-09 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.012 sec. to    0.216 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.35453     ( -1.50275   1.51782 )
Epeak [keV] : 209.683      ( -210.031 -210.031 )
Norm@50keV  : 1.82421E-02    ( -0.018267   0.0832349 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.16 using 59 PHA bins.
# Reduced chi-squared =          1.217 for     56 degrees of freedom 
# Null hypothesis probability =   1.277756e-01
 
Photon flux (15-150 keV)    in 0.204 sec: 1.89530 ( -0.37958  0.36834 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.83324e-08 ( -7.57917e-09  4.80846e-09 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from   -0.384 sec. to    0.616 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.28194     ( -0.506561   0.516997 )
Norm@50keV  : 3.92435E-03    ( -0.00113948   0.00113917 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.15 using 59 PHA bins.
# Reduced chi-squared =         0.8623 for     57 degrees of freedom 
# Null hypothesis probability =   7.606453e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.466672 ( -0.139839  0.141333 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.89574e-08 ( -1.21996e-08  1.2492e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from   -0.384 sec. to    0.616 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.228918     ( -1.87867   4.38295 )
Epeak [keV] : 81.6745      ( -30.3469 -81.675 )
Norm@50keV  : 1.88157E-02    ( -0.018816   0.966343 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.93 using 59 PHA bins.
# Reduced chi-squared =         0.8559 for     56 degrees of freedom 
# Null hypothesis probability =   7.698997e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.429430 ( -0.151893  0.153017 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.57808e-08 ( -1.25492e-08  1.34538e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 0.1719999 sec.
Hardness ratio (energy fluence ratio) = 1.40607968897

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

    S(15-50 keV)  = 1.1325866e-08
S(50-150 keV) = 1.8157536e-08

    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 = 2.413613012851211E-01, IMY = 2.934972487999810E-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 0.012000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9914 -15.6290    0.3  36.8  -35.4  11.0677  38.5    1.0	Sco X-1                       
254.4862  35.3010    2.1  41.7 -122.3   3.0056   5.6    2.9	Her X-1                       
256.4363 -36.4226   28.2  58.6  -24.6  -0.5161  -0.4    0.1	GX 349+2                      
217.9715 -12.7768    2.3  22.6   11.7   1.0604   5.1 ------	UNKNOWN                       
194.6483  64.3165    5.0  56.9  179.2   3.0634   2.3 ------	UNKNOWN                       
235.2787 -31.0277    3.1  44.0  -10.1   1.2410   3.7 ------	UNKNOWN                       
237.6448  20.0085    2.9  21.3 -109.6   0.8942   3.9 ------	UNKNOWN                       
249.2227 -23.5676    2.9  45.1  -30.7   1.4218   4.0 ------	UNKNOWN

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

    Time interval of the image:
0.012000 0.216000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
245.1278 -15.7412    0.0  36.9  -35.4  -0.0056  -0.7   10.5	Sco X-1                       
254.3811  35.3833    3.9  41.6 -122.5  -0.0420  -3.0    4.5	Her X-1                       
256.3819 -36.4673    4.6  58.6  -24.5   0.0865   2.5    3.7	GX 349+2                      
177.0559  52.3907    2.8  54.0  161.3   0.1164   4.2 ------	UNKNOWN                       
226.3771 -46.3851    2.3  56.7    4.4   0.1388   5.0 ------	UNKNOWN                       
192.8818  63.6299    2.4  56.7  177.9   0.1321   4.8 ------	UNKNOWN                       
225.9512   2.2044    2.3  10.8  -34.6   0.0249   5.0 ------	UNKNOWN                       
236.4376  -0.3607    1.3  20.8  -50.6   0.0475   8.8 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
62.124600 962.701900
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
244.9760 -15.6333    0.2  17.5  -31.7  45.2120  77.1    0.5	Sco X-1                       
254.4550  35.3534    1.6  39.5 -159.6   7.1087   7.4    0.7	Her X-1                       
255.8338 -37.9453   67.8  41.6  -26.3   0.1745   0.2    9.4	4U 1700-377                   
256.3859 -36.3945    5.4  40.5  -28.1   2.0797   2.1    2.9	GX 349+2                      
263.1583 -24.7722   81.9  35.6  -47.7   0.1298   0.1    8.3	GX 1+4                        
264.6692 -44.4777    4.4  50.7  -28.9   4.0693   2.6    3.6	4U 1735-44                    
268.2504  -1.4948    3.4  31.9  -90.8   3.5107   3.4    7.5	SW J1753.5-0127               
270.4358 -24.9733    7.8  41.1  -53.6   2.2056   1.5   10.4	GX 5-1                        
270.4246 -25.5863    5.9  41.4  -52.8   3.1063   2.0   11.5	GRS 1758-258                  
274.0094 -13.9156    4.3  39.6  -71.4   4.7146   2.7    7.3	GX 17+2                       
275.8374 -30.2636    5.8  47.9  -50.7   5.8541   2.0    7.7	H1820-303                     
263.0014 -33.8951    2.5  41.8  -36.9   5.1748   4.7    3.7	GX 354-0                      
269.7316  51.1748    3.8  58.8 -159.3  14.8451   3.1 ------	UNKNOWN                       
272.5304 -33.9715    2.7  47.7  -44.4   8.6622   4.2 ------	UNKNOWN                       
275.6183 -37.8963    2.4  52.0  -42.3  15.7233   4.8 ------	UNKNOWN