GRB090531B

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 16:04:42 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger353728
======================================================================

  Trigger: 00353728      Segment: 000

  BAT Trigger Time: 265487760.96   [s; MET]
      Trigger Stop: 265487761.984   [s; MET]
               UTC: 2009-05-31T18:35:56.171780    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 252.064493860549   Dec: -36.0245188355297  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    11.06
     Image Trigger?:     NO
     Rate S/N Ratio:     48.4148737476408  [ if not an image trigger ]
     Image S/N Ratio:    11.06

  Analysis Position:   [ source = BAT ]
    RA: 252.064493860549   Dec: -36.0245188355297  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 252.050663288647   Dec: -36.0371248300275  [deg; J2000]  
        { 16h 48m 12.2s , -36d 02' 13.6" }
         +/- 1.63203383503178 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.668135944031281 [arcmin] (formal 1-sigma fit error)
    SNR: 15.1084385497323
 
  Angular difference between the analysis and refined position is 1.011157 arcmin
 
  Partial Coding Fraction: 1.015625    [ including projection effects ]

  Duration
     T90: 54.9959999918938 +/- 6.13174035585667
        Measured from: 0.439999997615814
                   to: 55.4359999895096     [s; relative to TRIGTIME]
     T50: 39.6159999966621 +/- 13.3353342529601
        Measured from: 1.60400000214577
                   to: 41.2199999988079     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.25     
                   to: 1.25     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.252000004053116     
                   to: 56.1319999992847     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.345998   0.326109   0.291201   0.099008
           0.041058   0.038554   0.032767   0.027373 [error]
 Peak      0.049357   0.071327   0.087462   0.033839
           0.006112   0.006192   0.006156   0.005358 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   55.880    0.252   56.132
T90    54.996    0.440   55.436
T50    39.616    1.604   41.220
Peak    1.000    0.250    1.250
 
 
====== 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      -1.516    -0.215      0.214       -           -               -         1.16e-03     -1.32e-04          1.31e-04      57.410   57
CPL     -1.528    -0.800      0.232     9999.360      N/A           N/A         1.15e-03        N/A               N/A         57.440   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      -0.948     -0.157     0.160       -           -               -         1.52e-02     -1.25e-03          1.24e-03      63.270   57
CPL     -0.879     -0.230     0.346      973.617    -973.617      -973.617      1.62e-02     -2.20e-03          5.27e-03      63.650   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   8.40e-08  1.53e-07  2.14e-07  6.25e-07  6.13e-07  1.08e-06   erg/cm2
      90%_error_low -1.64e-08 -1.78e-08 -3.31e-08 -1.90e-07 -7.70e-08 -2.17e-07   erg/cm2
      90%_error_hi   1.73e-08  1.76e-08  3.27e-08  2.43e-07  7.80e-08  2.61e-07   erg/cm2
Peak flux       PL   3.69e-01  5.16e-01  5.36e-01  1.02e+00  1.74e+00  2.44e+00   ph/cm2/s
      90%_error_low -6.52e-02 -5.54e-02 -4.87e-02 -2.00e-01 -1.45e-01 -2.28e-01   ph/cm2/s
      90%_error_hi   6.99e-02  5.45e-02  4.82e-02  2.32e-01  1.45e-01  2.39e-01   ph/cm2/s
 
Fluence        CPL   8.40e-08  1.49e-07  2.10e-07  7.10e-07  6.19e-07  1.07e-06   erg/cm2
      90%_error_low -1.65e-08 -1.41e-08 -2.98e-08 -3.69e-07 -8.28e-08 -2.81e-07   erg/cm2
      90%_error_hi   1.73e-08  2.12e-08  3.60e-08  4.28e-08  7.23e-08  2.63e-07   erg/cm2
Peak flux      CPL   3.68e-01  5.17e-01  5.34e-01  1.09e+00  1.76e+00  2.44e+00   ph/cm2/s
      90%_error_low     N/A   -5.65e-02 -4.76e-02     N/A   -1.58e-01 -3.58e-01   ph/cm2/s
      90%_error_hi      N/A    2.73e-02  5.02e-02     N/A    1.32e-01  2.14e-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
  252.0507   -36.0371   0.0128    12.5680    11.9314         1.1102854     15.108 TRIG_00353728                 
 
Foreground time interval of the image:
  0.252  56.132 (delta_t =  55.880 [sec])
Background time interval of the image:
-620.859 -588.914 (delta_t =  31.945 [sec])
-239.960   0.252 (delta_t = 240.212 [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    0.252 sec. to   56.132 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.51636     ( -0.214969   0.213755 )
Norm@50keV  : 1.15968E-03    ( -0.000132126   0.000130726 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.41 using 59 PHA bins.
# Reduced chi-squared =          1.007 for     57 degrees of freedom 
# Null hypothesis probability =   4.599344e-01
 
Photon flux (15-150 keV)    in 55.88 sec: 0.145424 ( -0.016303  0.016361 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.13222e-07 ( -7.70222e-08  7.80146e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.252 sec. to   56.132 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.24222     ( -0.0863455   0.946285 )
Epeak [keV] : 88.2551      (   )
Norm@50keV  : 5.03494E-04    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.26 using 59 PHA bins.
# Reduced chi-squared =          1.005 for     56 degrees of freedom 
# Null hypothesis probability =   4.651582e-01
 
Photon flux (15-150 keV)    in 55.88 sec: 0.145410 ( -0.016324  0.016348 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.18709e-07 ( -8.28058e-08  7.22568e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    0.250 sec. to    1.250 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.94778     ( -0.157323   0.160264 )
Norm@50keV  : 1.51740E-02    ( -0.00124851   0.00124428 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.27 using 59 PHA bins.
# Reduced chi-squared =          1.110 for     57 degrees of freedom 
# Null hypothesis probability =   2.647724e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.74321 ( -0.14456  0.14505 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.67244e-07 ( -1.53292e-08  1.54566e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.250 sec. to    1.250 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.941505     ( -0.230062   0.346287 )
Epeak [keV] : 9999.34      ( -9999.36 -9999.36 )
Norm@50keV  : 1.52675E-02    ( -0.00123586   0.00622998 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.30 using 59 PHA bins.
# Reduced chi-squared =          1.130 for     56 degrees of freedom 
# Null hypothesis probability =   2.344573e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.75580 ( -0.15786  0.13173 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.67174e-07 ( -1.53432e-08  1.54593e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 54.996 sec.
Hardness ratio (energy fluence ratio) = 1.39829875367

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

S(15-50 keV)  = 2.3689093e-07
S(50-150 keV) = 3.763261e-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 = 2.181239179977716E-01,

Spacecraft aspect plot

Bright

Pre-burst

 Time interval of the image: -620.859400 -588.914100 -239.960000 0.252000

# RAcent #  [deg] 186.5126 -62.8308 244.9810 -15.6459 256.1170 -37.9571 256.4445 -36.2562 263.0750 -24.7385 264.6794 -44.6523 268.4600  -1.5643 270.3489 -24.9037 270.0844 -25.6986 274.0591 -14.1202 275.9500 -30.3410 285.0799 -24.7402 288.7317  10.9861 263.0026 -33.8071 272.3470   5.1837 298.7033  -3.3383 266.5305 -32.2150 255.7339 -48.7818 318.7937  -9.9223

Pre-slew

 Time interval of the image: 0.252000 56.132000

# RAcent #  [deg] 186.7303 -62.6898 245.0617 -15.4728 256.1125 -37.7552 256.4427 -36.4639 263.1013 -24.5991 264.6794 -44.6523 268.3268  -1.3117 270.4583 -25.0427 270.2567 -25.6778 273.9573 -13.9876 276.1381 -30.3587 285.0517 -24.7115 288.7593  11.0518 262.7950 -33.8584 297.4851  13.1479 252.0507 -36.0371

Post-slew

 Time interval of the image: 167.340600 359.440600

# RAcent #  [deg] 255.9226 -37.6909 256.3846 -36.2588 262.7880 -24.7429 264.8863 -44.3455 270.2751 -25.2474 270.2057 -25.8517 273.9591 -13.9820 275.8730 -30.3687 285.0938 -25.1172 263.0273 -33.8412 266.5544 -32.2027 301.7597   0.7174 347.1660 -60.6274

IMY = -4.609093939030418E-02 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] ['] 5.5 57.2 -24.2 -2.7111 -2.1 5.4 GX 301-2 0.4 25.7 68.6 9.1132 31.5 0.4 Sco X-1 4.9 10.3 -3.2 0.4758 2.3 9.2 4U 1700-377 4.1 9.3 5.0 0.5800 2.8 10.0 GX 349+2 3.4 8.1 100.4 0.6786 3.4 3.6 GX 1+4 0.0 12.5 -50.4 0.8069 3.9 12.4 4U 1735-44 5.7 30.7 127.1 0.6494 2.0 8.7 SW J1753.5-0127 10.6 8.1 148.7 0.2106 1.1 11.1 GX 5-1 13.3 7.2 149.5 0.1738 0.9 12.1 GRS 1758-258 2.2 19.4 145.9 1.1141 5.2 5.9 GX 17+2 1.8 8.3 -157.5 1.3246 6.5 2.0 H1820-303 9.0 17.9 -166.7 -0.2759 -1.3 11.1 HT1900.1-2455 2.9 48.2 153.2 3.2118 4.0 4.6 GRS 1915+105 2.0 3.4 4.9 1.2292 5.6 1.8 GX 354-0 2.5 37.8 132.9 2.2301 4.7 ------ UNKNOWN 2.7 41.8 176.3 1.4520 4.3 ------ UNKNOWN 1.2 0.0 99.8 2.1004 9.8 ------ UNKNOWN 2.4 18.4 -33.5 1.0238 4.9 ------ UNKNOWN 3.8 53.0 -159.3 1.8913 3.0 ------ UNKNOWN background subtracted image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 3.9 57.1 -24.1 -1.1342 -2.9 5.2 GX 301-2 7.5 25.7 69.0 -0.1616 -1.5 11.1 Sco X-1 11.2 10.2 -2.3 -0.0787 -1.0 8.0 4U 1700-377 5.6 9.3 3.9 0.1612 2.1 2.5 GX 349+2 9.4 8.2 101.0 0.0956 1.2 10.1 GX 1+4 0.0 12.5 -50.4 -0.1309 -1.7 12.4 4U 1735-44 51.2 31.0 126.9 -0.0288 -0.2 8.8 SW J1753.5-0127 7.1 8.0 149.8 0.1293 1.6 9.7 GX 5-1 6.5 7.3 150.6 0.1438 1.8 4.6 GRS 1758-258 6.7 19.5 145.4 -0.1435 -1.7 4.1 GX 17+2 5.0 8.4 -157.1 -0.1723 -2.3 11.0 H1820-303 0.0 17.9 -166.8 -0.0926 -1.2 12.6 HT1900.1-2455 4.3 48.2 153.2 -0.7185 -2.7 6.8 GRS 1915+105 4.9 3.5 5.4 -0.1924 -2.4 9.8 GX 354-0 2.4 54.2 161.5 2.3801 4.9 ------ UNKNOWN 0.8 12.6 11.9 1.1104 15.2 ------ UNKNOWN image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 21.5 26.1 59.1 0.1060 0.5 9.7 4U 1700-377 6.9 26.2 62.4 0.3266 1.7 10.2 GX 349+2 0.0 27.7 90.7 0.3869 1.7 12.0 GX 1+4 6.0 18.3 44.3 -0.2768 -1.9 8.8 4U 1735-44 117.7 22.6 101.4 -0.0177 -0.1 10.1 GX 5-1 6.7 22.2 100.3 0.3119 1.7 8.4 GRS 1758-258 6.2 30.4 121.5 0.4468 1.9 4.2 GX 17+2 1.2 15.5 102.5 1.3739 9.2 2.7 H1820-303 0.0 16.5 138.1 0.1274 0.8 12.2 HT1900.1-2455 3.3 22.2 73.2 0.6644 3.5 1.9 GX 354-0 2.2 20.4 81.2 1.0210 5.3 ------ UNKNOWN 2.2 43.3 170.4 1.5141 5.3 ------ UNKNOWN 3.0 39.5 -68.1 2.1671 3.7 ------ 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