GRB090915

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 GROUND-DETECTED GRB DATA PROCESSING REPORT                 
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Sun May 10 03:04:20 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================

  Trigger: 00362785      Segment: 000

  BAT Trigger Time: 274721739.2
               UTC: 2009-09-15T15:35:34.112   [includes UTCF correction]
       Where From?: Ground analysis (best_duration.txt)
  NOTE: BAT trigger time for ground-detected burst is the T100 start time.
 
  Analysis Position:   [ source = GCN ]
    RA: 237.991   Dec: 15.483  [deg; J2000]
 
  Refined Position:   [ source = BAT pre-slew image ]
    RA: 237.991   Dec: 15.483  [deg; J2000]
        { 15h 51m 57.8s , +15d 28' 58.8" }
        +/- 2.95711299957 [arcmin] (estimated 90% radius based on SNR)
    SNR: 6.46408025625
 
 
  Angular difference between the analysis and refined position is 0.000000 arcmin
 
  Partial Coding Fraction: 0.08789062    [ including projection effects ]

  Duration
     T90: 9.60000002384186 +/- 1.6
        Measured from: 0
                   to: 9.6     [s; relative to TRIGTIME]
     T50: 6.40000003576279 +/- 1.6
        Measured from: 1.6
                   to: 8     [s; relative to TRIGTIME]
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    9.600    0.000    9.600
T90     9.600    0.000    9.600
T50     6.400    1.600    8.000
Peak    1.000    3.500    4.500
 
 
====== 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      -1.059    -0.364      0.390       -           -               -         9.84e-03     -2.30e-03          2.27e-03      54.850   57
CPL      1.696    -2.361      5.630       80.704     -17.148       113.381      1.30e-01     -1.30e-01          1.23e+01      50.580   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
 
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      -0.515     -0.904     0.515       -           -               -         9.89e-03     -7.20e-03          6.61e-03      66.910   57
CPL      0.769     -0.769    -0.769      148.455    -148.455      -148.455      2.81e-02     -2.81e-02          1.11e+02      66.520   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   6.51e-08  1.57e-07  3.02e-07  1.42e-06  8.16e-07  1.94e-06   erg/cm2
      90%_error_low -2.76e-08 -4.54e-08 -6.95e-08 -6.04e-07 -1.83e-07 -6.52e-07   erg/cm2
      90%_error_hi   3.35e-08  4.52e-08  6.89e-08  8.69e-07  1.84e-07  8.71e-07   erg/cm2
Peak flux       PL   1.60e-01  2.91e-01  4.07e-01  1.19e+00  1.17e+00  2.05e+00   ph/cm2/s
      90%_error_low -1.60e-01 -2.91e-01 -4.07e-01 -1.19e+00 -1.17e+00 -1.06e+00   ph/cm2/s
      90%_error_hi   3.25e-01  2.87e-01  2.07e-01  3.78e+00  7.27e-01  3.09e+00   ph/cm2/s
 
Fluence        CPL   2.75e-08  1.63e-07  3.74e-07  2.16e-07  7.27e-07  7.80e-07   erg/cm2
      90%_error_low -2.47e-08 -6.46e-08 -9.47e-08 -1.70e-07 -2.01e-07 -2.51e-07   erg/cm2
      90%_error_hi   4.20e-08  5.66e-08  1.01e-07  7.23e-07  2.05e-07  7.09e-07   erg/cm2
Peak flux      CPL   7.40e-02  2.70e-01  4.98e-01  4.00e-01  1.10e+00  1.24e+00   ph/cm2/s
      90%_error_low -7.40e-02 -2.70e-01 -2.87e-01 -4.00e-01 -6.29e-01 -7.73e-01   ph/cm2/s
      90%_error_hi   3.76e-01  3.26e-01  3.28e-01  1.75e+00  7.41e-01  2.24e+00   ph/cm2/s
 
======================================================================

Special notes of this burst

Image

15.0-350.0 keV image (Event data)

#RAcent DECcent POSerr Theta  Phi  Peak_Cts  SNR Name
237.991 15.483 0.000 54.520 -28.267 1.046 6.464 TRIG_00362785
 
Image time interval: 0.000 to 7.824 [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.

Best duration plot

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    0.000 sec. to    7.824 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.05874     ( -0.364644   0.390199 )
Norm@50keV  : 9.84124E-03    ( -0.00230339   0.00226739 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.85 using 59 PHA bins.
# Reduced chi-squared =         0.9624 for     57 degrees of freedom 
# Null hypothesis probability =   5.559899e-01
 
Photon flux (15-150 keV)    in 7.824 sec: 1.13732 ( -0.272072  0.2789 ) ph/cm2/s
Energy fluence (15-150 keV)             : 8.16051e-07 ( -1.82999e-07  1.83647e-07 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.000 sec. to    7.824 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.6965     ( -2.36687   5.62386 )
Epeak [keV] : 80.7036      ( -17.0895 113.44 )
Norm@50keV  : 0.129578    ( -0.130637   12.3317 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.58 using 59 PHA bins.
# Reduced chi-squared =         0.9032 for     56 degrees of freedom 
# Null hypothesis probability =   6.794616e-01
 
Photon flux (15-150 keV)    in 7.824 sec: 0.986664 ( -0.291102  0.302286 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.27309e-07 ( -2.01366e-07  2.05363e-07 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    3.500 sec. to    4.500 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.515155     ( -0.90442   0.515155 )
Norm@50keV  : 9.88590E-03    ( -0.00720468   0.00661275 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.91 using 59 PHA bins.
# Reduced chi-squared =          1.174 for     57 degrees of freedom 
# Null hypothesis probability =   1.734910e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.16798 ( -1.16798  0.72732 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.31817e-07 ( -6.56121e-08  6.56343e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    3.500 sec. to    4.500 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.768697     ( -0.811707   -0.811707 )
Epeak [keV] : 148.455      ( -143.165 -143.165 )
Norm@50keV  : 2.80525E-02    ( -0.031109   110.918 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.52 using 59 PHA bins.
# Reduced chi-squared =          1.188 for     56 degrees of freedom 
# Null hypothesis probability =   1.585994e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.09589 ( -0.6285  0.74064 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.26579e-07 ( -7.47587e-08  6.86346e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 9.6 sec.
Hardness ratio (energy fluence ratio) = 1.92048128925

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

S(15-50 keV)  = 2.2212697e-07
S(50-150 keV) = 5.939297e-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 = 1.23569112544,

Spacecraft aspect plot

Bright

Event

 Time interval of the image: 1.888000 7.823800

# RAcent #  [deg] 244.9701 -15.6278 255.8780 -37.6995 256.5822 -36.4424 262.9847 -24.5973 264.9101 -44.5555 268.3495  -1.4661 270.4445 -25.0417 270.1264 -25.6966 274.1227 -13.8683 276.0595 -30.1904 285.0935 -24.8525 288.8903  10.9199 262.9842 -33.9852 279.2708 -65.1665 234.0497 -54.5511 238.4227 -30.2314 237.9899  15.4815

 Webpage updated on: Wed Nov 25 14:11:02 EST 2015

IMY = 0.664425214753 source in the event data image

data image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 1.5 25.8 -51.1 0.2957 7.7 0.9 Sco X-1 6.6 11.9 -120.2 -0.0566 -1.7 10.1 4U 1700-377 8.3 10.8 -116.0 0.0444 1.4 7.2 GX 349+2 16.0 7.6 -27.1 0.0222 0.7 9.0 GX 1+4 6.0 13.8 -163.8 -0.0588 -1.9 9.6 4U 1735-44 5.6 29.5 8.9 0.0792 2.0 1.4 SW J1753.5-0127 5.1 6.4 30.4 0.0705 2.3 9.0 GX 5-1 7.5 5.6 30.1 0.0480 1.5 9.9 GRS 1758-258 0.0 18.0 28.1 0.0469 1.5 12.2 GX 17+2 0.0 7.2 93.9 0.0477 1.5 12.7 H1820-303 3.3 16.5 80.3 0.1264 3.5 5.1 HT1900.1-2455 7.2 46.5 36.9 0.1748 1.6 5.6 GRS 1915+105 5.1 5.0 -120.8 0.0659 2.2 9.0 GX 354-0 2.6 35.0 179.3 0.1887 4.4 ------ UNKNOWN 2.0 33.6 -136.8 0.2544 5.7 ------ UNKNOWN 2.7 25.2 -88.3 0.1880 4.3 ------ UNKNOWN 1.9 54.5 -28.3 0.8805 6.2 ------ UNKNOWN

Analysis Summary

Notes:

Image

15.0-350.0 keV image (Event data)

Light Curves

Best duration plot

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