GRB150811A

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 Aug 30 18:08:19 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger651882
======================================================================

  Trigger: 00651882      Segment: 000

  BAT Trigger Time: 460958784   [s; MET]
      Trigger Stop: 460958848   [s; MET]
               UTC: 2015-08-11T04:06:09.022920    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 291.370844486993   Dec: -15.4381283909325  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    10.67
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    10.67

  Analysis Position:   [ source = BAT ]
    RA: 291.370844486993   Dec: -15.4381283909325  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 291.345175381785   Dec: -15.4375489483609  [deg; J2000]  
        { 19h 25m 22.8s , -15d 26' 15.2" }
         +/- 1.94642539453502 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.955325865879976 [arcmin] (formal 1-sigma fit error)
    SNR: 11.746854162161
 
  Angular difference between the analysis and refined position is 1.484985 arcmin
 
  Partial Coding Fraction: 0.6796875    [ including projection effects ]

  Duration
     T90: 31.5199999213219 +/- 7.31887482514508
        Measured from: 4.63200002908707
                   to: 36.1519999504089     [s; relative to TRIGTIME]
     T50: 16.3719999790192 +/- 4.58665973285042
        Measured from: 6.81599998474121
                   to: 23.1879999637604     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 5.00800001621246     
                   to: 6.00800001621246     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 1.50800001621246     
                   to: 39.1840000152588     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.399911   0.350962   0.177710   0.047599
           0.043803   0.042855   0.035459   0.029779 [error]
 Peak      0.035260   0.023839   0.004236   0.007794
           0.007388   0.007240   0.005969   0.004816 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   37.676    1.508   39.184
T90    31.520    4.632   36.152
T50    16.372    6.816   23.188
Peak    1.000    5.008    6.008
 
 
====== 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      -2.133    -0.276      0.254       -           -               -         1.37e-03     -2.52e-04          2.44e-04      64.320   57
CPL     -1.943    -0.059      1.004       12.492     -11.507       -12.492      1.77e-03     -7.44e-04          2.84e-04      64.280   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      -2.264     -0.657     0.542       -           -               -         3.53e-03     -1.55e-03          1.51e-03      69.780   57
CPL     -1.080     -1.036     4.250       26.277      N/A           N/A         2.12e-02        N/A               N/A         69.430   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   1.20e-07  1.50e-07  1.37e-07  2.18e-07  4.82e-07  6.26e-07   erg/cm2
      90%_error_low -2.15e-08 -2.04e-08 -3.36e-08 -8.95e-08 -7.68e-08 -1.34e-07   erg/cm2
      90%_error_hi   2.20e-08  2.02e-08  3.49e-08  1.24e-07  7.90e-08  1.60e-07   erg/cm2
Peak flux       PL   3.04e-01  1.96e-01  8.15e-02  4.62e-02  6.05e-01  6.28e-01   ph/cm2/s
      90%_error_low -1.10e-01 -6.12e-02 -4.28e-02 -4.62e-02 -1.75e-01 -1.84e-01   ph/cm2/s
      90%_error_hi   1.14e-01  5.94e-02  4.87e-02  6.61e-02  1.75e-01  1.86e-01   ph/cm2/s
 
Fluence        CPL   1.20e-07  1.52e-07  1.36e-07  1.62e-07  4.75e-07  5.47e-07   erg/cm2
      90%_error_low -1.35e-08 -5.19e-08 -3.72e-08 -1.05e-07 -8.71e-08    N/A      erg/cm2
      90%_error_hi   1.84e-08  1.95e-08  3.46e-08  2.24e-07  8.63e-08    N/A      erg/cm2
Peak flux      CPL   3.04e-01  2.02e-01  7.59e-02  2.11e-02  6.00e-01  6.09e-01   ph/cm2/s
      90%_error_low -5.57e-02 -5.98e-02 -3.92e-02     N/A       N/A       N/A     ph/cm2/s
      90%_error_hi   1.08e-01  5.99e-02  5.31e-02     N/A       N/A       N/A     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
  291.3452   -15.4375   0.0163    26.5224   148.2921         1.0188307     11.747 TRIG_00651882                 
 
Foreground time interval of the image:
  1.508  39.184 (delta_t =  37.676 [sec])
Background time interval of the image:
-657.799 -641.960 (delta_t =  15.839 [sec])
-239.000   1.508 (delta_t = 240.508 [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    1.508 sec. to   39.184 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.13329     ( -0.276406   0.254418 )
Norm@50keV  : 1.37258E-03    ( -0.000251992   0.000243695 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.32 using 59 PHA bins.
# Reduced chi-squared =          1.128 for     57 degrees of freedom 
# Null hypothesis probability =   2.357457e-01
 
Photon flux (15-150 keV)    in 37.68 sec: 0.219579 ( -0.028788  0.028793 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.82281e-07 ( -7.67813e-08  7.89746e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    1.508 sec. to   39.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.98917     ( -0.0135251   1.04969 )
Epeak [keV] : 3.08674      ( -2.10237 -3.08674 )
Norm@50keV  : 1.66785E-03    ( -0.000643069   0.00038526 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.26 using 59 PHA bins.
# Reduced chi-squared =          1.148 for     56 degrees of freedom 
# Null hypothesis probability =   2.096082e-01
 
Photon flux (15-150 keV)    in 37.68 sec: 0.219480 ( -0.028718  0.028989 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.749e-07 ( -8.7106e-08  8.6343e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    5.008 sec. to    6.008 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.26352     ( -0.656778   0.541795 )
Norm@50keV  : 3.52993E-03    ( -0.00154539   0.00150508 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.78 using 59 PHA bins.
# Reduced chi-squared =          1.224 for     57 degrees of freedom 
# Null hypothesis probability =   1.191376e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.604680 ( -0.17525  0.175296 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.35243e-08 ( -1.18193e-08  1.28343e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    5.008 sec. to    6.008 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.07978     ( -1.0393   4.2468 )
Epeak [keV] : 26.2770      (   )
Norm@50keV  : 2.11528E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.43 using 59 PHA bins.
# Reduced chi-squared =          1.240 for     56 degrees of freedom 
# Null hypothesis probability =   1.072432e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.600323 (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 31.52 sec.
Hardness ratio (energy fluence ratio) = 0.91177964254

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

S(15-50 keV)  = 2.705635e-07
S(50-150 keV) = 2.1171969e-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 = -4.245781518859776E-01,

Spacecraft aspect plot

Bright

Pre-burst

 Time interval of the image: -657.799400 -641.960400 -239.000000 1.508000

# RAcent #  [deg] 244.9992 -15.6510 254.5157  35.4567 255.9517 -37.7334 256.3361 -36.4331 262.9965 -24.7174 268.5477  -1.3859 270.1884 -24.9991 270.2972 -25.7354 274.0012 -14.0690 275.8025 -30.3269 285.1496 -24.8359 288.7380  11.1417 299.6061  35.1940 308.1187  40.9487 326.2391  38.4064 263.0898 -33.7659 321.2322  60.7343 262.6145  -9.1646 279.0023  44.1678 243.5150 -28.2896 254.0192  24.1111 UNKNOWN UNKNOWN

Pre-slew

 Time interval of the image: 1.508000 39.184000

# RAcent #  [deg] 244.8666 -15.6987 254.5094  35.3664 255.9669 -37.7533 256.3771 -36.4592 262.9217 -24.6582 268.3891  -1.4645 270.1323 -25.1134 270.3764 -25.8373 273.8257 -14.0956 275.9144 -30.4012 285.1486 -24.9936 288.8297  10.7634 299.5573 308.2117  40.8769 326.2145  38.4018 263.0281 -33.9642 303.4457 -32.0951 291.3452 -15.4376 271.1877  51.9901

Post-slew

 Time interval of the image: 127.900600 963.029200

# RAcent #  [deg] 255.8812 -37.7257 256.4468 -36.2771 263.1924 -24.6528 264.8536 -44.4751 268.3433  -1.4557 270.1927 -25.0520 270.3452 -25.7400 273.9912 -13.9876 275.9446 -30.3562 285.1664 -24.9456 288.8840  10.9689 299.5912  35.2151 263.0091 -33.8820 329.5509 -42.2013 301.0617 -21.4815 289.6131 -69.4596 287.2265  39.6041 263.1813   6.9679

IMY = -2.623057113130498E-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] ['] 0.8 50.8 -146.9 9.5036 13.9 1.3 Sco X-1 5.7 39.5 -72.2 1.3814 2.0 7.4 Her X-1 45.4 57.6 -175.6 -0.3224 -0.3 6.8 4U 1700-377 7.0 56.4 -174.9 1.6671 1.6 4.8 GX 349+2 17.1 43.6 -171.2 -0.2704 -0.7 1.8 GX 1+4 6.2 23.6 -146.5 0.4557 1.8 11.5 SW J1753.5-0127 17.9 40.3 -179.6 0.2168 0.6 7.1 GX 5-1 7.7 40.9 179.7 0.5322 1.5 0.5 GRS 1758-258 2.8 29.0 -175.5 1.0405 4.1 2.0 GX 17+2 8.8 43.1 170.3 0.5524 1.3 6.8 H1820-303 19.3 36.0 159.5 0.2309 0.6 8.0 HT1900.1-2455 15.1 0.2 -35.5 -0.1596 -0.8 12.3 GRS 1915+105 0.5 26.2 -5.7 4.9906 21.9 0.9 Cyg X-1 1.3 34.5 0.1 2.6351 9.1 0.4 Cyg X-3 56.1 43.2 18.0 -0.0884 -0.2 6.0 Cyg X-2 3.4 51.0 -178.5 2.0911 3.4 6.5 GX 354-0 3.8 55.2 -7.5 2.3562 3.0 ------ UNKNOWN 2.3 32.9 -152.9 1.2740 4.9 ------ UNKNOWN 2.4 34.3 -38.6 1.3946 4.7 ------ UNKNOWN 4.2 58.8 -159.1 4.2232 2.8 ------ UNKNOWN 2.8 35.5 -89.7 2.3269 4.2 ------ UNKNOWN background subtracted image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 4.5 51.0 -146.9 -0.5187 -2.6 7.4 Sco X-1 4.6 39.5 -72.3 -0.4625 -2.5 2.9 Her X-1 5.0 57.6 -175.6 0.9451 2.3 5.5 4U 1700-377 7.9 56.4 -175.0 -0.4729 -1.5 3.6 GX 349+2 3.6 43.6 -171.1 0.3566 3.2 7.1 GX 1+4 18.8 23.8 -146.4 -0.0435 -0.6 1.5 SW J1753.5-0127 88.7 40.4 -179.6 0.0135 0.1 8.5 GX 5-1 6.7 40.9 179.6 0.1846 1.7 6.9 GRS 1758-258 2.8 29.1 -175.2 -0.3120 -4.1 11.1 GX 17+2 5.9 43.2 170.1 -0.2540 -1.9 2.1 H1820-303 6.3 36.1 159.4 -0.2045 -1.8 7.5 HT1900.1-2455 6.0 0.2 136.9 -0.1205 -1.9 11.1 GRS 1915+105 35.2354 465.7 26.2 -5.9 0.0018 0.0 2.6 Cyg X-1 6.9 34.5 0.3 -0.1358 -1.7 6.5 Cyg X-3 5.4 43.2 18.0 -0.2781 -2.1 5.2 Cyg X-2 11.4 51.2 -178.6 0.1855 1.0 8.0 GX 354-0 2.6 45.3 136.3 1.2407 4.5 ------ UNKNOWN 1.0 26.5 148.3 1.0188 11.7 ------ UNKNOWN 2.4 43.4 -41.8 0.6550 4.9 ------ UNKNOWN image of 15-350 keV band DECcent POSerr Theta Phi PeakCts SNR AngSep Name [deg] ['] [deg] [deg] ['] 17.9 38.4 -136.0 -0.7941 -0.6 8.7 4U 1700-377 7.8 37.4 -134.2 1.7370 1.5 8.8 GX 349+2 0.0 28.0 -117.4 -2.6238 -2.6 11.4 GX 1+4 56.9 36.7 -151.4 -0.1885 -0.2 5.0 4U 1735-44 26.4 26.7 -64.2 0.3999 0.4 1.5 SW J1753.5-0127 3.9 22.0 -122.9 2.1989 3.0 5.2 GX 5-1 2.7 22.2 -124.8 3.1398 4.2 2.3 GRS 1758-258 2.2 16.9 -91.0 3.6413 5.2 3.1 GX 17+2 1.9 20.6 -142.9 4.3527 6.2 1.2 H1820-303 4.3 11.2 -153.3 1.8312 2.7 7.3 HT1900.1-2455 8.7 26.5 -9.1 0.9762 1.3 5.2 GRS 1915+105 1.4 51.2 5.0 14.5869 8.2 0.8 Cyg X-1 4.3 31.5 -134.7 2.3961 2.7 3.0 GX 354-0 3.1 42.3 133.5 9.7188 3.8 ------ UNKNOWN 2.9 11.0 121.2 2.9696 4.0 ------ UNKNOWN 5.0 54.1 177.1 7.4143 2.3 ------ UNKNOWN 3.4 55.2 -7.5 7.7025 3.4 ------ UNKNOWN 2.4 35.8 -56.9 5.1447 4.7 ------ 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