GRB090916

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: Sun Jan 19 14:02:56 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger362818
======================================================================

  Trigger: 00362818      Segment: 000

  BAT Trigger Time: 274777249.216   [s; MET]
      Trigger Stop: 274777249.472   [s; MET]
               UTC: 2009-09-16T07:00:44.126400    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 126.579580098003   Dec: 25.9332286507725  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.61
     Image Trigger?:     NO
     Rate S/N Ratio:     16.3707055437449  [ if not an image trigger ]
     Image S/N Ratio:    7.61

  Analysis Position:   [ source = BAT ]
    RA: 126.579580098003   Dec: 25.9332286507725  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 126.581805863008   Dec: 25.9412643299174  [deg; J2000]  
        { 08h 26m 19.6s , +25d 56' 28.6" }
         +/- 2.72216737789302 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.27283070148402 [arcmin] (formal 1-sigma fit error)
    SNR: 7.27463967585148
 
  Angular difference between the analysis and refined position is 0.496873 arcmin
 
  Partial Coding Fraction: 0.3476562    [ including projection effects ]

  Duration
     T90: 62.4480000138283 +/- 14.7346123240447
        Measured from: 0.135999977588654
                   to: 62.5839999914169     [s; relative to TRIGTIME]
     T50: 39.1840000152588 +/- 16.6127180809248
        Measured from: 3.17599999904633
                   to: 42.3600000143051     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: -0.0360000133514404     
                   to: 0.96399998664856     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.0400000214576721     
                   to: 68.5199999809265     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.405278   0.348867   0.462067   0.115727
           0.081764   0.085634   0.076099   0.067760 [error]
 Peak      0.057950   0.077486   0.068387   0.018180
           0.011092   0.011995   0.011185   0.009093 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   68.560   -0.040   68.520
T90    62.448    0.136   62.584
T50    39.184    3.176   42.360
Peak    1.000   -0.036    0.964
 
 
====== 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      -1.381    -0.327      0.332       -           -               -         1.41e-03     -2.58e-04          2.58e-04      53.570   57
CPL     -1.246    -2.086      1.286      310.230    -310.230      -310.230      1.63e-03     -4.73e-04          4.18e-03      53.600   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      -1.405     -0.278     0.280       -           -               -         1.57e-02     -2.50e-03          2.50e-03      57.740   57
CPL     -1.366     -1.747     0.982      878.440    -878.440      -878.440      1.64e-02     -3.16e-03          -1.64e-02      57.770   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   1.11e-07  2.18e-07  3.35e-07  1.13e-06  9.39e-07  1.79e-06   erg/cm2
      90%_error_low -3.69e-08 -4.69e-08 -7.42e-08 -4.66e-07 -1.82e-07 -5.27e-07   erg/cm2
      90%_error_hi   4.10e-08  4.55e-08  7.23e-08  6.50e-07  1.83e-07  6.71e-07   erg/cm2
Peak flux       PL   5.90e-01  6.28e-01  4.75e-01  5.83e-01  1.91e+00  2.28e+00   ph/cm2/s
      90%_error_low -1.69e-01 -1.17e-01 -9.01e-02 -2.02e-01 -3.21e-01 -3.64e-01   ph/cm2/s
      90%_error_hi   1.84e-01  1.14e-01  8.83e-02  2.58e-01  3.22e-01  3.66e-01   ph/cm2/s
 
Fluence        CPL   1.10e-07  2.20e-07  3.36e-07  1.11e-06  9.38e-07  1.61e-06   erg/cm2
      90%_error_low -4.17e-08 -4.79e-08 -7.43e-08 -8.56e-07 -1.89e-07 -7.14e-07   erg/cm2
      90%_error_hi   2.95e-08  5.08e-08  8.77e-08  3.60e-07  1.73e-07  1.16e-06   erg/cm2
Peak flux      CPL   5.93e-01  6.27e-01  4.73e-01  5.98e-01  1.92e+00  2.29e+00   ph/cm2/s
      90%_error_low -1.96e-01 -1.15e-01 -8.83e-02     N/A   -3.27e-01 -3.88e-01   ph/cm2/s
      90%_error_hi   1.09e-01  1.28e-01  5.27e-02     N/A    3.23e-01  3.42e-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
  126.5818    25.9413   0.0264    48.1543   -11.2567         1.3361193      7.275 TRIG_00362818                 
 
Foreground time interval of the image:
 -0.040  68.520 (delta_t =  68.560 [sec])
Background time interval of the image:
-228.115  -0.040 (delta_t = 228.075 [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:

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   -0.040 sec. to   68.520 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.38111     ( -0.326937   0.33223 )
Norm@50keV  : 1.41099E-03    ( -0.000258271   0.000258265 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.57 using 59 PHA bins.
# Reduced chi-squared =         0.9398 for     57 degrees of freedom 
# Null hypothesis probability =   6.046438e-01
 
Photon flux (15-150 keV)    in 68.56 sec: 0.171113 ( -0.033526  0.033771 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.38538e-07 ( -1.82401e-07  1.83301e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.040 sec. to   68.520 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.3776     ( -2.0744   1.2971 )
Epeak [keV] : 9994.99      ( -9994.51 -9994.51 )
Norm@50keV  : 1.41632E-03    ( -0.000259238   0.00439447 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.57 using 59 PHA bins.
# Reduced chi-squared =         0.9566 for     56 degrees of freedom 
# Null hypothesis probability =   5.675058e-01
 
Photon flux (15-150 keV)    in 68.56 sec: 0.171117 ( -0.034982  0.033719 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.38449e-07 ( -1.88726e-07  1.72619e-07 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from   -0.036 sec. to    0.964 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.4046     ( -0.277919   0.280438 )
Norm@50keV  : 1.57039E-02    ( -0.00250349   0.00249888 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.74 using 59 PHA bins.
# Reduced chi-squared =          1.013 for     57 degrees of freedom 
# Null hypothesis probability =   4.476255e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.91449 ( -0.32058  0.32234 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.51618e-07 ( -2.59282e-08  2.60749e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.036 sec. to    0.964 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.40149     ( -1.7462   0.983157 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 1.57606E-02    ( -0.00251156   -0.0157609 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.74 using 59 PHA bins.
# Reduced chi-squared =          1.031 for     56 degrees of freedom 
# Null hypothesis probability =   4.105856e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.91696 ( -0.32727  0.32258 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.51813e-07 ( 0  0 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 62.448 sec.
Hardness ratio (energy fluence ratio) = 1.53574869273

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

S(15-50 keV)  = 3.289038e-07
S(50-150 keV) = 6.096383e-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 = 1.095162537365787E+00, IMY = 2.179748825138327E-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:
-228.115410 -0.040000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5118  35.4727   13.0  53.2  164.8   0.8780   0.9    8.3	Her X-1                       
175.7302  65.8599    2.9  15.5   79.6   0.7134   4.0 ------	UNKNOWN                       
226.1916  50.5981    2.5  28.0  160.6   0.9284   4.6 ------	UNKNOWN                       
145.9188  42.1892    2.7  25.6   -7.1   0.8095   4.2 ------	UNKNOWN

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

Time interval of the image:
-0.040000 68.520000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5940  35.3256   47.3  53.4  164.9  -0.1001  -0.2    6.8	Her X-1                       
126.5818  25.9413    1.6  48.2  -11.3   1.3357   7.3 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
-336.216000 962.909800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5316  35.4380  124.4  53.3  164.8   0.3838   0.1    6.8	Her X-1                       
 93.6445  56.9637    3.3  48.6   41.7   8.6165   3.6 ------	UNKNOWN                       
219.5155  46.5745    2.3  25.3  172.4   3.2544   5.0 ------	UNKNOWN                       
114.7405  28.6317    2.7  53.8    0.7   8.5761   4.2 ------	UNKNOWN                       
123.3364  31.6095    2.7  46.3   -3.0   5.4919   4.3 ------	UNKNOWN                       
235.0452  18.8056    3.2  52.8 -165.1   7.4810   3.6 ------	UNKNOWN                       
122.8730  18.3583    3.8  56.1  -14.5   7.5602   3.1 ------	UNKNOWN

Analysis Summary

Notes:

Image

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

Light Curves

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:

Time averaged spectrum fit using the average DRM

Power-law model

Cutoff power-law model

1-s peak spectrum fit

Power-law model

Cutoff power-law model

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

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

Mask shadow pattern

Spacecraft aspect plot

Bright source in the pre-burst/pre-slew/post-slew images

Pre-burst image of 15-350 keV band

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

Post-slew image of 15-350 keV band

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