GRB090423

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 17:21:17 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger350184
======================================================================

  Trigger: 00350184      Segment: 000

  BAT Trigger Time: 262166124.032   [s; MET]
      Trigger Stop: 262166125.056   [s; MET]
               UTC: 2009-04-23T07:55:19.349660    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 148.894774542363   Dec: 18.160243227552  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.16
     Image Trigger?:     NO
     Rate S/N Ratio:     11.2694276695846  [ if not an image trigger ]
     Image S/N Ratio:    8.16

  Analysis Position:   [ source = BAT ]
    RA: 148.894774542363   Dec: 18.160243227552  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 148.889545872   Dec: 18.1659867564125  [deg; J2000]  
        { 09h 55m 33.5s , +18d 09' 57.6" }
         +/- 1.06308019948789 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.351888802339676 [arcmin] (formal 1-sigma fit error)
    SNR: 27.8719214680514
 
  Angular difference between the analysis and refined position is 0.455647 arcmin
 
  Partial Coding Fraction: 0.921875    [ including projection effects ]

  Duration
     T90: 10.3039999902248 +/- 1.05554725375129
        Measured from: 0.30799999833107
                   to: 10.6119999885559     [s; relative to TRIGTIME]
     T50: 4.84000000357628 +/- 0.4
        Measured from: 2.99599999189377
                   to: 7.83599999547005     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 3.61599999666214     
                   to: 4.61599999666214     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.668000012636185     
                   to: 11.7400000095367     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.369549   0.513486   0.272211   0.034315
           0.019339   0.020579   0.017684   0.014653 [error]
 Peak      0.061842   0.084085   0.052852   0.006485
           0.005985   0.006447   0.005645   0.004337 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   12.408   -0.668   11.740
T90    10.304    0.308   10.612
T50     4.840    2.996    7.836
Peak    1.000    3.616    4.616
 
 
====== 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: CPL)
 
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      -1.808    -0.093      0.091       -           -               -         6.00e-03     -3.44e-04          3.42e-04      63.750   57
CPL     -0.765    -0.442      0.497       53.230      -5.830         9.472      2.21e-02     -9.26e-03          1.90e-02      45.100   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      -1.649     -0.155     0.151       -           -               -         1.33e-02     -1.29e-03          1.27e-03      44.360   57
CPL     -1.224     -0.498     0.664       85.977     -30.084       -85.977      2.25e-02     -9.98e-03          2.79e-02      42.800   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   1.27e-07  1.94e-07  2.21e-07  4.82e-07  6.85e-07  1.02e-06   erg/cm2
      90%_error_low -1.02e-08 -1.00e-08 -1.70e-08 -7.20e-08 -3.99e-08 -8.89e-08   erg/cm2
      90%_error_hi   1.04e-08  1.00e-08  1.71e-08  7.99e-08  4.02e-08  9.49e-08   erg/cm2
Peak flux       PL   6.33e-01  5.84e-01  3.72e-01  3.65e-01  1.74e+00  1.95e+00   ph/cm2/s
      90%_error_low -8.70e-02 -5.25e-02 -4.61e-02 -8.23e-02 -1.54e-01 -1.75e-01   ph/cm2/s
      90%_error_hi   8.99e-02  5.24e-02  4.59e-02  9.54e-02  1.54e-01  1.76e-01   ph/cm2/s
 
Fluence        CPL   1.11e-07  2.15e-07  2.20e-07  1.18e-07  6.24e-07  6.64e-07   erg/cm2
      90%_error_low -1.20e-08 -1.35e-08 -2.03e-08 -4.84e-08 -4.53e-08 -6.60e-08   erg/cm2
      90%_error_hi   1.21e-08  1.38e-08  1.98e-08  8.18e-08  4.63e-08  9.12e-08   erg/cm2
Peak flux      CPL   5.97e-01  6.12e-01  3.82e-01  2.18e-01  1.72e+00  1.81e+00   ph/cm2/s
      90%_error_low -1.01e-01 -6.49e-02 -4.97e-02 -1.10e-01 -1.59e-01 -2.00e-01   ph/cm2/s
      90%_error_hi   1.02e-01  6.72e-02  5.07e-02  1.79e-01  1.58e-01  2.56e-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
  148.8895    18.1660   0.0069    25.0329  -172.0965         1.1413986     27.872 TRIG_00350184                 
 
Foreground time interval of the image:
 -0.668  10.669 (delta_t =  11.337 [sec])
Background time interval of the image:
-30.331  -0.668 (delta_t =  29.663 [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   -0.668 sec. to   11.740 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.80835     ( -0.0928842   0.0913861 )
Norm@50keV  : 6.00078E-03    ( -0.000344025   0.000341766 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.75 using 59 PHA bins.
# Reduced chi-squared =          1.118 for     57 degrees of freedom 
# Null hypothesis probability =   2.510726e-01
 
Photon flux (15-150 keV)    in 12.41 sec: 0.829629 ( -0.043693  0.043738 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.85491e-07 ( -3.99086e-08  4.02e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.668 sec. to   11.740 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.764922     ( -0.442235   0.496928 )
Epeak [keV] : 53.2296      ( -5.82968 9.47164 )
Norm@50keV  : 2.20761E-02    ( -0.00926473   0.0189616 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.10 using 59 PHA bins.
# Reduced chi-squared =         0.8054 for     56 degrees of freedom 
# Null hypothesis probability =   8.510667e-01
 
Photon flux (15-150 keV)    in 12.41 sec: 0.789227 ( -0.046427  0.046502 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.24485e-07 ( -4.52672e-08  4.62514e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    3.616 sec. to    4.616 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.64895     ( -0.155164   0.151241 )
Norm@50keV  : 1.33376E-02    ( -0.00128587   0.00127092 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.36 using 59 PHA bins.
# Reduced chi-squared =         0.7783 for     57 degrees of freedom 
# Null hypothesis probability =   8.888824e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.74103 ( -0.15437  0.15444 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.24077e-07 ( -1.26706e-08  1.28219e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    3.616 sec. to    4.616 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.22392     ( -0.498235   0.66405 )
Epeak [keV] : 85.9769      ( -30.0838 -85.9769 )
Norm@50keV  : 2.25041E-02    ( -0.00998011   0.0278535 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.80 using 59 PHA bins.
# Reduced chi-squared =         0.7643 for     56 degrees of freedom 
# Null hypothesis probability =   9.026979e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.71509 ( -0.15859  0.15842 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.19903e-07 ( -1.40118e-08  1.40307e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 10.304 sec.
Hardness ratio (energy fluence ratio) = 1.02004707455

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

S(15-50 keV)  = 3.264334e-07
S(50-150 keV) = 2.9804464e-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 = -4.625712549329783E-01, IMY = 6.421546464279676E-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:
-30.331400 -0.668000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']

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

Time interval of the image:
-0.668000 10.668590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
173.3315  -7.9001    2.5  46.6  136.4   0.7632   4.7 ------	UNKNOWN                       
148.8895  18.1660    0.4  25.0 -172.1   1.1413  27.9 ------	UNKNOWN

Post-slew image of 15-350 keV band

Time interval of the image:
56.668600 718.368600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
171.8137 -15.3837    2.8  40.4  122.8   4.2765   4.1 ------	UNKNOWN                       
199.9093  44.4618    2.6  49.8   24.7   6.2192   4.4 ------	UNKNOWN                       
143.8336 -35.9680    2.2  54.4  163.2  10.2847   5.3 ------	UNKNOWN                       
133.7167 -21.6997    2.6  42.6  179.3   2.5525   4.5 ------	UNKNOWN                       
116.6207 -17.2765    3.3  47.6 -158.2   2.4617   3.5 ------	UNKNOWN                       
109.0433  53.8552    3.8  47.0  -53.0   5.6618   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