GRB090726

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 15:06:44 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger358422
======================================================================

  Trigger: 00358422      Segment: 000

  BAT Trigger Time: 270340952.704   [s; MET]
      Trigger Stop: 270340964.864   [s; MET]
               UTC: 2009-07-26T22:42:27.759160    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 248.818572808623   Dec: 72.8709899504922  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    11.07
     Image Trigger?:     NO
     Rate S/N Ratio:     12.9614813968157  [ if not an image trigger ]
     Image S/N Ratio:    11.07

  Analysis Position:   [ source = BAT ]
    RA: 248.818572808623   Dec: 72.8709899504922  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 248.668069969593   Dec: 72.8654666541818  [deg; J2000]  
        { 16h 34m 40.3s , +72d 51' 55.7" }
         +/- 1.60485878981529 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.601212186275245 [arcmin] (formal 1-sigma fit error)
    SNR: 15.4752331601455
 
  Angular difference between the analysis and refined position is 2.680583 arcmin
 
  Partial Coding Fraction: 0.859375    [ including projection effects ]

  Duration
     T90: 56.6759999394417 +/- 12.1653910790061
        Measured from: -17.0600000023842
                   to: 39.6159999370575     [s; relative to TRIGTIME]
     T50: 20.2399999499321 +/- 10.5583568518411
        Measured from: -2.50800001621246
                   to: 17.7319999337196     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 7.66000002622604     
                   to: 8.66000002622604     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -18.1919999718666     
                   to: 47.244000017643     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.693290   0.621410   0.228138   0.057155
           0.046892   0.048931   0.044944   0.043603 [error]
 Peak      0.022513   0.049390   0.018696   0.009778
           0.006236   0.006584   0.005904   0.005483 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   65.436  -18.192   47.244
T90    56.676  -17.060   39.616
T50    20.240   -2.508   17.732
Peak    1.000    7.660    8.660
 
 
====== 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      -2.288    -0.196      0.184       -           -               -         1.26e-03     -1.72e-04          1.70e-04      56.880   57
CPL     -1.303    -0.816      1.002       26.882      N/A           N/A         5.00e-03        N/A               N/A         52.390   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      -1.791     -0.334     0.313       -           -               -         5.77e-03     -1.34e-03          1.31e-03      69.940   57
CPL      1.622     -2.157     4.169       40.314      -6.509        10.881      6.72e-01     -6.72e-01          2.60e+02      61.810   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   2.22e-07  2.53e-07  2.08e-07  2.85e-07  7.86e-07  9.67e-07   erg/cm2
      90%_error_low -2.63e-08 -2.45e-08 -3.81e-08 -8.95e-08 -8.73e-08 -1.42e-07   erg/cm2
      90%_error_hi   2.67e-08  2.43e-08  3.99e-08  1.15e-07  8.99e-08  1.61e-07   erg/cm2
Peak flux       PL   3.14e-01  2.66e-01  1.54e-01  1.32e-01  7.92e-01  8.66e-01   ph/cm2/s
      90%_error_low -8.26e-02 -5.21e-02 -4.45e-02 -6.05e-02 -1.55e-01 -1.74e-01   ph/cm2/s
      90%_error_hi   8.64e-02  5.21e-02  4.59e-02  8.53e-02  1.55e-01  1.76e-01   ph/cm2/s
 
Fluence        CPL   2.08e-07  2.80e-07  2.01e-07  2.86e-07  7.87e-07  9.61e-07   erg/cm2
      90%_error_low -2.98e-08 -3.28e-08    N/A       N/A    -8.74e-08 -1.36e-07   erg/cm2
      90%_error_hi   2.96e-08  3.36e-08    N/A       N/A     8.99e-08  1.88e-07   erg/cm2
Peak flux      CPL   2.42e-01  3.77e-01  1.09e-01  2.54e-03  7.31e-01  7.31e-01   ph/cm2/s
      90%_error_low -9.75e-02 -8.51e-02 -6.18e-02 -2.54e-03 -1.50e-01 -1.50e-01   ph/cm2/s
      90%_error_hi   1.02e-01  8.70e-02  6.87e-02  2.77e-02  1.53e-01  1.53e-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
  248.6681    72.8655   0.0124    28.5121  -171.9119         1.7255312     15.475 TRIG_00358422                 
 
Foreground time interval of the image:
-18.192  47.244 (delta_t =  65.436 [sec])
Background time interval of the image:
-239.704 -18.192 (delta_t = 221.512 [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  -18.192 sec. to   47.244 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.28768     ( -0.196456   0.18418 )
Norm@50keV  : 1.26004E-03    ( -0.000172481   0.000170153 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.88 using 59 PHA bins.
# Reduced chi-squared =         0.9979 for     57 degrees of freedom 
# Null hypothesis probability =   4.794585e-01
 
Photon flux (15-150 keV)    in 65.44 sec: 0.218729 ( -0.019669  0.019669 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.86379e-07 ( -8.73212e-08  8.99218e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from  -18.192 sec. to   47.244 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.30258     ( -0.816592   1.00145 )
Epeak [keV] : 26.8822      (   )
Norm@50keV  : 5.00431E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.39 using 59 PHA bins.
# Reduced chi-squared =         0.9355 for     56 degrees of freedom 
# Null hypothesis probability =   6.123665e-01
 
Photon flux (15-150 keV)    in 65.44 sec: 0.210768 ( -0.020433  0.020527 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.86523e-07 ( -8.74167e-08  8.98583e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    7.660 sec. to    8.660 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.79112     ( -0.333885   0.313207 )
Norm@50keV  : 5.76548E-03    ( -0.00134129   0.00131337 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.94 using 59 PHA bins.
# Reduced chi-squared =          1.227 for     57 degrees of freedom 
# Null hypothesis probability =   1.165512e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.791795 ( -0.154866  0.154866 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.3097e-08 ( -1.22961e-08  1.27794e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    7.660 sec. to    8.660 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.62201     ( -2.18898   4.13679 )
Epeak [keV] : 40.3137      ( -6.41929 10.9713 )
Norm@50keV  : 0.672492    ( -0.76088   259.66 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.81 using 59 PHA bins.
# Reduced chi-squared =          1.104 for     56 degrees of freedom 
# Null hypothesis probability =   2.765168e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.731221 ( -0.150228  0.15295 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.04837e-08 ( -9.23946e-09  1.15878e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 56.676 sec.
Hardness ratio (energy fluence ratio) = 0.819256822759

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

S(15-50 keV)  = 4.752566e-07
S(50-150 keV) = 3.111345e-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 = -5.378266925416157E-01, IMY = 7.642997650182753E-02

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:
-239.704000 -18.192000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
325.9915  38.2038    4.0  39.9   92.1  -2.1039  -2.9   11.0	Cyg X-2                       
169.6959  59.4686    2.8  46.7 -127.7   2.9144   4.1 ------	UNKNOWN

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

Time interval of the image:
-18.192000 47.244000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
325.9943  38.2364    6.5  39.9   92.1   0.7507   1.8    9.8	Cyg X-2                       
 25.7155  45.0097    2.4  30.0   11.6   0.5565   4.9 ------	UNKNOWN                       
248.6680  72.8654    0.7  28.5 -171.9   1.7257  15.5 ------	UNKNOWN                       
 55.0272  31.0986    2.1  49.3  -18.3   1.1346   5.5 ------	UNKNOWN                       
 54.3301  22.2860    2.4  57.6  -14.6   2.3473   4.9 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
474.596640 962.317100
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
178.5766  71.4714    3.3  17.9   33.9   1.0979   3.5 ------	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