GRB080906

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 22:56:04 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger323984
======================================================================

  Trigger: 00323984      Segment: 000

  BAT Trigger Time: 242400799.424   [s; MET]
      Trigger Stop: 242400800.448   [s; MET]
               UTC: 2008-09-06T13:33:16.347220    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 227.890126999499   Dec: -80.4861395765144  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    6.72
     Image Trigger?:     NO
     Rate S/N Ratio:     10.6301458127346  [ if not an image trigger ]
     Image S/N Ratio:    6.72

  Analysis Position:   [ source = BAT ]
    RA: 227.890126999499   Dec: -80.4861395765144  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 228.057031570565   Dec: -80.537933222545  [deg; J2000]  
        { 15h 12m 13.7s , -80d 32' 16.6" }
         +/- 1.62491979375274 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.678895355668262 [arcmin] (formal 1-sigma fit error)
    SNR: 15.203021510086
 
  Angular difference between the analysis and refined position is 3.518845 arcmin
 
  Partial Coding Fraction: 0.59375    [ including projection effects ]

  Duration
     T90: 148.212000012398 +/- 19.610295759031
        Measured from: -67.7319999933243
                   to: 80.4800000190735     [s; relative to TRIGTIME]
     T50: 40.66400000453 +/- 5.79279036844568
        Measured from: 2.69200000166893
                   to: 43.3560000061989     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 8.24000000953674     
                   to: 9.24000000953674     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -104.995999991894     
                   to: 109.555999994278     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.635900   2.296052   1.603514   0.307856
           0.085671   0.087392   0.077216   0.069248 [error]
 Peak      0.032740   0.050433   0.041392   0.006256
           0.006790   0.006956   0.006267   0.005383 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  214.552 -104.996  109.556
T90   148.212  -67.732   80.480
T50    40.664    2.692   43.356
Peak    1.000    8.240    9.240
 
 
====== 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      -1.517    -0.085      0.084       -           -               -         1.80e-03     -8.30e-05          8.27e-05      43.810   57
CPL     -1.391    -0.169      0.325      243.417    -243.417      -243.417      2.08e-03     -3.50e-04          9.14e-04      43.320   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      -1.399     -0.268     0.267       -           -               -         8.40e-03     -1.35e-03          1.35e-03      37.570   57
CPL     -0.398     -1.100     1.558       80.126     -22.165       -80.126      2.67e-02     -2.67e-02          1.25e-01      35.440   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   5.01e-07  9.10e-07  1.27e-06  3.72e-06  3.65e-06  6.40e-06   erg/cm2
      90%_error_low -4.08e-08 -4.42e-08 -7.72e-08 -4.76e-07 -1.84e-07 -5.33e-07   erg/cm2
      90%_error_hi   4.19e-08  4.40e-08  7.70e-08  5.23e-07  1.85e-07  5.72e-07   erg/cm2
Peak flux       PL   3.14e-01  3.35e-01  2.54e-01  3.14e-01  1.02e+00  1.22e+00   ph/cm2/s
      90%_error_low -8.23e-02 -5.78e-02 -5.02e-02 -1.10e-01 -1.64e-01 -1.98e-01   ph/cm2/s
      90%_error_hi   8.88e-02  5.71e-02  4.97e-02  1.42e-01  1.65e-01  2.01e-01   ph/cm2/s
 
Fluence        CPL   4.89e-07  9.21e-07  1.28e-06  3.04e-06  3.61e-06  5.73e-06   erg/cm2
      90%_error_low -4.87e-08 -5.04e-08 -8.03e-08 -1.15e-06 -2.10e-07 -1.16e-06   erg/cm2
      90%_error_hi   4.58e-08  5.15e-08  8.12e-08  1.23e-06  2.08e-07  8.68e-07   erg/cm2
Peak flux      CPL   2.61e-01  3.66e-01  2.73e-01  1.19e-01  9.81e-01  1.02e+00   ph/cm2/s
      90%_error_low -1.02e-01 -6.91e-02 -5.80e-02 -1.19e-01 -1.73e-01 -1.98e-01   ph/cm2/s
      90%_error_hi   1.07e-01  7.26e-02  6.00e-02  2.40e-01  1.72e-01  2.91e-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
  228.0570   -80.5379   0.0127    26.2719  -109.9811         2.5864169     15.203 TRIG_00323984                 
 
Foreground time interval of the image:
-104.996  12.877 (delta_t = 117.873 [sec])
Background time interval of the image:
-239.424 -104.996 (delta_t = 134.428 [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 -104.996 sec. to  109.556 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.51673     ( -0.0845144   0.0843159 )
Norm@50keV  : 1.79826E-03    ( -8.30342e-05   8.27559e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.81 using 59 PHA bins.
# Reduced chi-squared =         0.7686 for     57 degrees of freedom 
# Null hypothesis probability =   9.000920e-01
 
Photon flux (15-150 keV)    in 214.6 sec: 0.225524 ( -0.010597  0.010615 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.65157e-06 ( -1.83884e-07  1.84882e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from -104.996 sec. to  109.556 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.39106     ( -0.169451   0.325186 )
Epeak [keV] : 243.417      ( -243.44 -243.44 )
Norm@50keV  : 2.07822E-03    ( -0.000350043   0.000913732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          43.32 using 59 PHA bins.
# Reduced chi-squared =         0.7736 for     56 degrees of freedom 
# Null hypothesis probability =   8.921391e-01
 
Photon flux (15-150 keV)    in 214.6 sec: 0.223829 ( -0.011341  0.011323 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.61028e-06 ( -2.09882e-07  2.08457e-07 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    8.240 sec. to    9.240 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.39868     ( -0.268493   0.267021 )
Norm@50keV  : 8.39811E-03    ( -0.00135394   0.00134742 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.57 using 59 PHA bins.
# Reduced chi-squared =         0.6590 for     57 degrees of freedom 
# Null hypothesis probability =   9.781528e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.02244 ( -0.164236  0.16457 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.11802e-08 ( -1.43889e-08  1.46142e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    8.240 sec. to    9.240 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.397876     ( -1.09961   1.55835 )
Epeak [keV] : 80.1256      ( -22.1651 -80.1256 )
Norm@50keV  : 2.67223E-02    ( -0.0267223   0.124731 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          35.44 using 59 PHA bins.
# Reduced chi-squared =         0.6329 for     56 degrees of freedom 
# Null hypothesis probability =   9.855320e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.980547 ( -0.172899  0.172283 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.53894e-08 ( -1.554e-08  1.6123e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 148.212 sec.
Hardness ratio (energy fluence ratio) = 1.39794467841

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

S(15-50 keV)  = 1.4109892e-06
S(50-150 keV) = 2.2405937e-06

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 = -1.686745831372712E-01,

Spacecraft aspect plot

Bright

Pre-burst

 Time interval of the image: -239.424000 -104.996000

# RAcent #  [deg] 255.9916 -37.8294 256.3341 -36.6013 263.0254 -24.7936 264.9367 -44.4435 270.1537 -25.0911 270.2622 -25.6393 274.0024 -13.8779 275.8684 -30.3305 285.0354 -24.8154 263.0750 -33.7885 297.6307 -48.9958 46.6900 -48.4586 51.2745 -47.1396

Pre-slew

 Time interval of the image: -104.996000 12.876590

# RAcent #  [deg] 256.0729 -37.7652 256.4493 -36.2660 263.0625 -24.5655 264.8774 -44.4134 270.1596 -25.1014 270.4175 -25.8296 273.9000 -13.9574 275.8411 -30.4818 284.8832 -24.9516 262.9046 -34.0209 277.7664 -11.7825 259.3095 -21.8655 53.3580 -56.6816 261.8082 -47.7604 228.0627 -80.5389

Post-slew

 Time interval of the image: 60.476600 962.575500

# RAcent #  [deg] 170.5644 -60.4682 186.8446 -62.7637 256.0026 -37.8379 256.3435 -36.2691 264.6618 -44.3051 263.0481 -33.7964 280.6092 -43.8186 55.2708 -50.0262 255.2687 -41.6151 83.5260 -66.3066 242.5725 -59.3413 86.3185 -40.5112 114.8976 -63.6684 116.3273 -46.9125 232.4010 -21.7986

IMY = 4.639067118422541E-01 source in the pre-burst/pre-slew/post-slew images

image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 1.0 37.0 -20.8 1.8181 11.6 0.9 4U 1700-377 8.0 37.9 -19.3 0.2279 1.4 11.8 GX 349+2 12.0 45.7 -3.3 0.2090 1.0 3.0 GX 1+4 7.1 27.7 -17.4 -0.2094 -1.6 8.3 4U 1735-44 4.5 42.9 5.1 0.5150 2.6 7.1 GX 5-1 4.1 42.4 4.9 0.5521 2.8 6.6 GRS 1758-258 5.7 52.5 14.5 1.0598 2.1 9.5 GX 17+2 5.4 36.3 9.7 0.3590 2.1 3.7 H1820-303 4.1 39.3 24.9 0.5925 2.8 6.3 HT1900.1-2455 2.7 37.5 -9.2 0.6293 4.2 5.1 GX 354-0 3.3 13.7 37.9 0.4331 3.5 ------ UNKNOWN 3.2 54.2 177.0 1.6905 3.5 ------ UNKNOWN 3.4 57.0 179.3 3.0214 3.4 ------ UNKNOWN background subtracted image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 5.2 37.0 -20.6 -0.4176 -2.2 6.3 4U 1700-377 14.8 38.1 -18.9 0.1487 0.8 9.4 GX 349+2 0.0 45.9 -3.1 0.2564 1.0 11.2 GX 1+4 5.1 27.8 -17.5 0.3356 2.3 6.2 4U 1735-44 7.8 42.9 5.1 -0.3478 -1.5 6.9 GX 5-1 3.8 42.2 5.0 0.6977 3.0 8.1 GRS 1758-258 2.7 52.4 14.3 -2.4471 -4.3 7.8 GX 17+2 11.5 36.1 9.6 -0.2018 -1.0 8.1 H1820-303 10.7 39.2 24.7 -0.2693 -1.1 8.5 HT1900.1-2455 0.0 37.4 -9.6 0.5665 3.3 11.9 GX 354-0 2.9 53.6 19.6 2.9837 4.0 ------ UNKNOWN 2.0 49.7 -5.9 1.8148 5.9 ------ UNKNOWN 2.5 49.6 -172.9 1.3408 4.6 ------ UNKNOWN 2.7 26.5 -25.7 0.5982 4.4 ------ UNKNOWN 0.8 26.3 -110.0 2.5726 15.1 ------ UNKNOWN image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 8.7 25.6 -102.1 0.8453 1.3 11.8 Cen X-3 2.7 21.0 -85.3 2.4737 4.2 5.2 GX 301-2 1.2 43.9 4.4 7.2485 9.7 0.8 4U 1700-377 9.7 45.5 4.5 1.0038 1.2 10.3 GX 349+2 10.3 38.4 15.5 -0.6801 -1.1 9.4 4U 1735-44 3.3 48.6 11.6 3.7430 3.5 3.7 GX 354-0 2.5 40.9 33.1 3.7896 4.6 ------ UNKNOWN 3.3 49.4 158.2 5.2818 3.5 ------ UNKNOWN 2.3 40.1 4.2 3.2594 5.0 ------ UNKNOWN 3.2 31.9 178.3 1.9076 3.6 ------ UNKNOWN 3.7 21.6 -7.5 1.4339 3.1 ------ UNKNOWN 4.3 57.2 -173.8 7.4876 2.7 ------ UNKNOWN 2.4 31.2 -156.0 2.3621 4.8 ------ UNKNOWN 3.0 47.3 -148.1 4.2273 3.9 ------ UNKNOWN 3.8 58.7 -23.2 10.1610 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

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