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
  250.1661    68.2247   0.0074    30.8365  -168.0504         2.2375506     25.994 TRIG_00557354                 
 
Foreground time interval of the image:
 -0.444  36.469 (delta_t =  36.913 [sec])
Background time interval of the image:
-330.931 -315.946 (delta_t =  14.986 [sec])
-239.632  -0.444 (delta_t = 239.188 [sec])
Lightcurves
Notes:
- 1) The mask-weighted light curves are using the flight position.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 5) Time of each bin is in the middle of the bin.
 1 s binning
 From T0-310 s to T0+310 s 
 
 From T100_start - 20 s to T100_end + 30 s 
 
 Full time interval 
 
 64 ms binning
 Full time interval 
 
 From T100_start to T100_end 
 
 From T0-5 sec to T0+5 sec 
 
 16 ms binning
 From T100_start-5 s to T100_start+5 s 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 8 ms binning
 From T100_start-3 s to T100_start+3 s
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 2 ms binning
 From T100_start-1 s to T100_start+1 s
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 SN=5 or 10 sec. binning (whichever binning is satisfied first)
 
 SN=5 or 10 sec. binning (T < 200 sec) 
 
 Quad-rate summed light curves (from T0-300s to T0+1000s)
 
 The mask-weighted light curves based on cleaned DPHs 
 
Spectral Evolution
 
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   -0.444 sec. to   95.768 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.62848     ( -0.142904   0.144571 )
Norm@50keV  : 1.71904E-03    ( -0.000139227   0.000137782 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.41 using 59 PHA bins.
# Reduced chi-squared =         0.9896 for     57 degrees of freedom 
# Null hypothesis probability =   4.973221e-01
 
Photon flux (15-150 keV)    in 96.21 sec: 0.222897 ( -0.0171512  0.0171897 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.54165e-06 ( -1.34041e-07  1.35361e-07 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from   -0.444 sec. to   95.768 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.39051     ( -0.153593   0.138413 )
Epeak [keV] : 137.740      ( -9999.35 -9999.36 )
Norm@50keV  : 7.00505E-04    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          54.46 using 59 PHA bins.
# Reduced chi-squared =         0.9725 for     56 degrees of freedom 
# Null hypothesis probability =   5.334147e-01
 
Photon flux (15-150 keV)    in 96.21 sec: 0.223272 ( -0.01772  0.016845 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.54288e-06 ( -1.3531e-07  1.27873e-07 ) ergs/cm2
 
Band function
 
Time interval is from   -0.444 sec. to   95.768 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 4.84248   ( -4.84248   -4.84248 )
beta        : -1.65812    ( -0.157968   0.151116 )
Epeak [keV] : 20.0077      ( -20.0077 4.89659 )
Norm@50keV   : 615.887    ( -46.259   1.09507e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.14 using 59 PHA bins.
# Reduced chi-squared =          1.021 for     55 degrees of freedom 
# Null hypothesis probability =   4.318186e-01
 
Photon flux (15-150 keV)    in 96.21 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 
Single BB
 
 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 12.2522  (  )
R^2/D10^2   : 4.82806E-02  (   )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =         119.12 using 59 PHA bins.
# Reduced chi-squared =         2.0899 for     57 degrees of freedom 
# Null hypothesis probability =   2.781312e-06
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.477e-07   2.136e-08
25- 50  4.762e-07   5.215e-08
50-150  4.358e-07   8.673e-08
15-150  1.060e-06   1.091e-07
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 180.090       (-62.9034      -178.727)
Norm        : 0.898193       (-0.0724232     0.087131)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.57 using 59 PHA bins.
# Reduced chi-squared =          1.063 for     57 degrees of freedom 
# Null hypothesis probability =   3.483481e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.179e-07   4.435e-08
25- 50  4.140e-07   1.430e-07
50-150  8.768e-07   4.463e-07
15-150  1.509e-06   7.038e-07
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 7.71139        (-1.17426      1.2403)
R1^2/D10^2  : 0.212801        (-0.0870975      0.170161)
kT2 [keV]   : 46.6966        (-15.4531      53.2469)
R2^2/D10^2  : 4.58943E-04    (-0.000381427   0.000995781)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.24 using 59 PHA bins.
# Reduced chi-squared =         0.9498 for     55 degrees of freedom 
# Null hypothesis probability =   5.808759e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  2.250e-07   4.320e-08
25- 50  4.297e-07   8.404e-08
50-150  9.799e-07   4.704e-07
15-150  1.635e-06   5.626e-07
Peak spectrum fit
Power-law model
 
Time interval is from   14.392 sec. to   15.392 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.31784     ( -0.427064   0.409536 )
Norm@50keV  : 6.40191E-03    ( -0.00143698   0.00143343 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.41 using 59 PHA bins.
# Reduced chi-squared =          1.025 for     57 degrees of freedom 
# Null hypothesis probability =   4.233681e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.766330 ( -0.176306  0.176986 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.29917e-08 ( -1.56844e-08  1.59809e-08 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from   14.392 sec. to   15.392 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.32660     ( -0.440716   0.401152 )
Epeak [keV] : 9999.35      ( -9999.36 -9999.36 )
Norm@50keV  : 6.39253E-03    ( -0.00144154   0.0218949 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.42 using 59 PHA bins.
# Reduced chi-squared =          1.043 for     56 degrees of freedom 
# Null hypothesis probability =   3.865780e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.768816 ( -0.177583  0.174404 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.31138e-08 ( -1.58622e-08  1.55112e-08 ) ergs/cm2
 
Band function
 
Time interval is from   14.392 sec. to   15.392 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 4.64018   ( -4.64018   -4.64018 )
beta        : -1.65480    ( -0.809592   0.602277 )
Epeak [keV] : 34.6587      ( -34.6587 39.5019 )
Norm@50keV   : 53.1275    ( -11.7918   3.34417e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.82 using 59 PHA bins.
# Reduced chi-squared =          1.051 for     55 degrees of freedom 
# Null hypothesis probability =   3.715239e-01
 
Photon flux (15-150 keV)    in 1 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 
Single BB
 
 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 13.5036  (-3.44874  5.91816)
R^2/D10^2   : 0.125556  (-0.0899733   0.232796)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          64.34 using 59 PHA bins.
# Reduced chi-squared =          1.129 for     57 degrees of freedom 
# Null hypothesis probability =   2.353304e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.849e-09   2.398e-09
25- 50  1.739e-08   8.661e-09
50-150  2.048e-08   1.155e-08
15-150  4.272e-08   1.883e-08
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 199.356       (-100.217      -199.36)
Norm        : 3.16667       (-0.714394     0.716187)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.68 using 59 PHA bins.
# Reduced chi-squared =          1.047 for     57 degrees of freedom 
# Null hypothesis probability =   3.784026e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  7.885e-09   4.802e-09
25- 50  1.517e-08   9.010e-09
50-150  3.327e-08   1.962e-08
15-150  5.632e-08   3.322e-08
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 9.75282        (-2.31225      2.31707)
R1^2/D10^2  : 0.331178        (-0.194181      0.342279)
kT2 [keV]   : 198.933        (-199.072      -199.072)
R2^2/D10^2  : 1.34744E-04    (-5.8605e-05   0.00155105)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.32 using 59 PHA bins.
# Reduced chi-squared =         0.9695 for     55 degrees of freedom 
# Null hypothesis probability =   5.388819e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  6.530e-09   3.783e-09
25- 50  1.671e-08   9.475e-09
50-150  4.298e-08   9.350e-09
15-150  6.622e-08   2.209e-08
Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)
Power-law model
 
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.39971     ( -0.114794   0.114439 )
Norm@50keV  : 3.86762E-03    ( -0.000241733   0.000241359 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.23 using 59 PHA bins.
# Reduced chi-squared =         0.8286 for     57 degrees of freedom 
# Null hypothesis probability =   8.185254e-01
 
Photon flux (15-150 keV)    in 36.91 sec: 0.470973 ( -0.0305355  0.0306144 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.37946e-06 ( -9.50038e-08  9.54843e-08 ) ergs/cm2
 
Cutoff power-law model
 
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.40044     ( -0.28783   0.112518 )
Epeak [keV] : 9999.26      ( -9999.35 -9999.35 )
Norm@50keV  : 3.87559E-03    ( -0.000241856   0.00139296 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.25 using 59 PHA bins.
# Reduced chi-squared =         0.8438 for     56 degrees of freedom 
# Null hypothesis probability =   7.910390e-01
 
Photon flux (15-150 keV)    in 36.91 sec: 0.470782 ( -0.030484  0.030588 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.37859e-06 ( -9.14371e-08  9.41463e-08 ) ergs/cm2
 
Band function
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 3.95618   ( -3.95691   -3.95691 )
beta        : -1.42118    ( -0.123719   0.121413 )
Epeak [keV] : 22.2146      ( -22.2134 107 )
Norm@50keV   : 114.378    ( -114.419   259715 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.82 using 59 PHA bins.
# Reduced chi-squared =         0.8512 for     55 degrees of freedom 
# Null hypothesis probability =   7.758098e-01
 
Photon flux (15-150 keV)    in 36.91 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 
 S(25-50 keV) vs. S(50-100 keV) plot 
 
S(25-50 keV)  = 4.05e-07
S(50-100 keV) = 5.24e-07
 T90 vs. Hardness ratio plot 
 
T90                                   = 76.2839999198914 sec.
Hardness ratio (energy fluence ratio) = 1.29383
 Color vs. Color plot 
 
Count Ratio  (25-50 keV) / (15-25 keV) = 1.21011
Count Ratio (50-100 keV) / (15-25 keV) = 0.758603
 Mask shadow pattern 
 
IMX = -5.840468575128441E-01, IMY = 1.236059627389259E-01
 TIME vs. PHA plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 TIME vs. DetID plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 100 us light curve (15-350 keV)
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 4.096000
 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:
-330.931340 -315.945500
-239.632000 -0.444000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.6033  35.4564    4.8  40.7  136.4   1.4890   2.4    9.9	Her X-1                       
299.6290  35.2064    1.7  18.3   70.9   1.7270   6.7    1.9	Cyg X-1                       
308.0904  40.9532    1.0  11.6   48.0   2.7311  11.7    0.9	Cyg X-3                       
326.1694  38.3489    7.3  19.1    0.2   0.3194   1.6    1.6	Cyg X-2                       
278.1197  48.4392    2.2  19.1  138.9   1.1697   5.3 ------	UNKNOWN                       
351.1074  42.2062    2.9  30.6  -38.3   1.0776   3.9 ------	UNKNOWN                       
179.5616  74.9184    2.4  48.0 -146.4   2.5340   4.8 ------	UNKNOWN                       
 Pre-slew background subtracted image of 15-350 keV band 
Time interval of the image:
-0.444000 36.468590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3079  35.2292    0.0  41.0  136.4   0.5892   2.5   10.0	Her X-1                       
299.6766  35.3340    3.3  18.2   70.9  -0.3213  -3.5    9.0	Cyg X-1                       
308.0717  41.0419    5.8  11.5   48.0  -0.1586  -2.0    5.6	Cyg X-3                       
325.9866  38.4012   21.5  19.0    0.5  -0.0427  -0.5    9.9	Cyg X-2                       
219.7454  60.3890    2.2  45.5 -174.3   0.7381   5.2 ------	UNKNOWN                       
250.1662  68.2247    0.4  30.8 -168.1   2.2372  26.0 ------	UNKNOWN                       
352.7754  26.7998    2.5  42.2  -20.7   0.5280   4.6 ------	UNKNOWN                       
 Post-slew image of 15-350 keV band 
Time interval of the image:
88.468600 238.460700
239.368000 450.568620
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.6122  35.3444    5.9  33.0   85.6   1.1820   1.9    7.6	Her X-1                       
299.6877  35.1268    6.6  43.0   26.5   0.9544   1.8    6.6	Cyg X-1                       
308.1110  40.9460    1.4  40.8   13.7   3.6155   8.2    0.4	Cyg X-3                       
326.0442  38.3572    7.4  49.7   -1.6   0.8394   1.6    6.4	Cyg X-2                       
176.4744  32.3259    4.5  54.2 -179.2   2.7179   2.6 ------	UNKNOWN                       
140.5822  50.7846    2.9  50.1 -138.5   4.8375   4.0 ------	UNKNOWN                       
 23.8928  62.8774    3.1  44.8  -59.8   4.9401   3.8 ------	UNKNOWN                       
 71.4606  70.9739    3.8  40.8  -88.3   4.2438   3.1 ------	UNKNOWN                       
Plot creation:
Sat May 30 16:39:12 EDT 2015