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
  237.6684   -62.0455   0.0100    31.2902   107.4480         1.6282712     19.151 TRIG_00315080                 
 
Foreground time interval of the image:
 -0.672  15.972 (delta_t =  16.644 [sec])
Background time interval of the image:
-299.227  -0.672 (delta_t = 298.555 [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 0.512000
 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 0.512000
 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 0.512000
 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)
 
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   -0.672 sec. to   15.972 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.27144     ( -0.150421   0.149756 )
Norm@50keV  : 6.38708E-03    ( -0.000510119   0.00050991 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.172 for     57 degrees of freedom 
# Null hypothesis probability =   1.758210e-01
 
Photon flux (15-150 keV)    in 16.64 sec: 0.758132 ( -0.062636  0.0628284 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.05776e-06 ( -9.49352e-08  9.56359e-08 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from   -0.672 sec. to   15.972 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.26705     ( -0.504749   0.15119 )
Epeak [keV] : 9989.60      ( -9996.09 -9996.09 )
Norm@50keV  : 6.41497E-03    ( -0.00641487   0.00438222 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.193 for     56 degrees of freedom 
# Null hypothesis probability =   1.529739e-01
 
Photon flux (15-150 keV)    in 16.64 sec: 0.758289 ( -0.063034  0.062302 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.05464e-06 ( -9.64005e-08  9.95971e-08 ) ergs/cm2
 
Band function
 
Time interval is from   -0.672 sec. to   15.972 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -1.02120   ( 1.02128   1.02128 )
beta        : -1.27144    ( -0.149721   0.150486 )
Epeak [keV] : 43.4118      ( -43.3769 -43.3769 )
Norm@50keV   : 1.19554E-02    ( -0.00607542   0.925442 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.215 for     55 degrees of freedom 
# Null hypothesis probability =   1.322636e-01
 
Photon flux (15-150 keV)    in 16.64 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]    : 18.8994  (-2.09352  2.43191)
R^2/D10^2   : 4.02353E-02  (-0.0131757   0.0191754)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =         104.96 using 59 PHA bins.
# Reduced chi-squared =         1.8413 for     57 degrees of freedom 
# Null hypothesis probability =   1.137118e-04
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  4.710e-08   7.413e-09
25- 50  2.257e-07   2.754e-08
50-150  5.918e-07   8.536e-08
15-150  8.645e-07   8.803e-08
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 200.000       (      )
Norm        : 3.13819       (-0.253774     0.253749)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          78.20 using 59 PHA bins.
# Reduced chi-squared =          1.372 for     57 degrees of freedom 
# Null hypothesis probability =   3.266637e-02
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.300e-07   1.385e-08
25- 50  2.501e-07   5.615e-08
50-150  5.485e-07   2.342e-07
15-150  9.286e-07   3.358e-07
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 6.36405        (-1.946      2.35696)
R1^2/D10^2  : 0.946955        (-0.623107      3.08234)
kT2 [keV]   : 29.1199        (-5.76548      10.9714)
R2^2/D10^2  : 8.61364E-03    (-0.00547816   0.00561769)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          67.44 using 59 PHA bins.
# Reduced chi-squared =          1.226 for     55 degrees of freedom 
# Null hypothesis probability =   1.211639e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.112e-07   5.187e-08
25- 50  2.218e-07   6.331e-08
50-150  7.264e-07   2.346e-07
15-150  1.059e-06   3.382e-07
Peak spectrum fit
Power-law model
 
Time interval is from    7.228 sec. to    8.228 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.28604     ( -0.2303   0.230203 )
Norm@50keV  : 1.60441E-02    ( -0.00227505   0.0022705 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.68 using 59 PHA bins.
# Reduced chi-squared =         0.8716 for     57 degrees of freedom 
# Null hypothesis probability =   7.435466e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.90928 ( -0.271443  0.271764 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.5909e-07 ( -2.51359e-08  2.54754e-08 ) ergs/cm2
 
Cutoff power-law model
 
Time interval is from    7.228 sec. to    8.228 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 9.65350E-02     ( -1.49496   1.07645 )
Epeak [keV] : 80.2675      ( -21.6225 237.381 )
Norm@50keV  : 6.35573E-02    ( -0.0636722   0.285769 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          46.06 using 59 PHA bins.
# Reduced chi-squared =         0.8226 for     56 degrees of freedom 
# Null hypothesis probability =   8.256104e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.82989 ( -0.28473  0.28279 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.45913e-07 ( -2.8063e-08  2.8621e-08 ) ergs/cm2
 
Band function
 
Time interval is from    7.228 sec. to    8.228 sec.
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : 0.428370   ( -1.2623   -0.44319 )
beta        : -2.03891    ( 2.04224   0.731124 )
Epeak [keV] : 65.6158      ( -33.2969 113.478 )
Norm@50keV   : 0.127034    ( -0.130155   87.4302 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.42 using 59 PHA bins.
# Reduced chi-squared =         0.8259 for     55 degrees of freedom 
# Null hypothesis probability =   8.179940e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.82557 ( 5.17443  -0.28232 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.47807e-07 ( -1.478e-07  -2.7343e-08 ) ergs/cm2
 
Single BB
 
 
Spectral model blackbody:
------------------------------------------------------------
Parameters  : value    Lower 90%  Upper 90%
kT [keV]    : 16.0757  (-2.33989  2.91238)
R^2/D10^2   : 0.185943  (-0.0809455   0.13232)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.07 using 59 PHA bins.
# Reduced chi-squared =         0.8608 for     57 degrees of freedom 
# Null hypothesis probability =   7.633933e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  9.925e-09   2.580e-09
25- 50  4.193e-08   8.435e-09
50-150  7.588e-08   2.134e-08
15-150  1.277e-07   2.545e-08
Thermal bremsstrahlung (OTTB)
 
 
 
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT [keV]    : 200.000       (      )
Norm        : 7.86750       (-1.11297     1.11293)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          51.52 using 59 PHA bins.
# Reduced chi-squared =         0.9039 for     57 degrees of freedom 
# Null hypothesis probability =   6.799999e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.959e-08   1.109e-08
25- 50  3.769e-08   2.080e-08
50-150  8.265e-08   4.645e-08
15-150  1.399e-07   7.855e-08
Double BB
 
 
 
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters  : value         Lower 90%    Upper 90%
kT1 [keV]   : 12.2327        (-9.90287      4.25584)
R1^2/D10^2  : 0.357130        (-0.198657      73.0028)
kT2 [keV]   : 43.3624        (-43.7683      -46.1659)
R2^2/D10^2  : 3.65401E-03    (-0.00271141   0.182874)
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.51 using 59 PHA bins.
# Reduced chi-squared =         0.8275 for     55 degrees of freedom 
# Null hypothesis probability =   8.154409e-01
 
Energy  Fluence     90% Error
[keV]   [erg/cm2]   [erg/cm2]
15- 25  1.215e-08   7.170e-09
25- 50  4.226e-08   2.586e-08
50-150  9.452e-08   4.819e-08
15-150  1.489e-07   7.724e-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: 1.27144     ( -0.150421   0.149756 )
Norm@50keV  : 6.38708E-03    ( -0.000510119   0.00050991 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.172 for     57 degrees of freedom 
# Null hypothesis probability =   1.758210e-01
 
Photon flux (15-150 keV)    in 16.64 sec: 0.758132 ( -0.062636  0.0628284 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.05776e-06 ( -9.49352e-08  9.56359e-08 ) ergs/cm2
 
Cutoff power-law model
 
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 1.26705     ( -0.504749   0.15119 )
Epeak [keV] : 9989.60      ( -9996.09 -9996.09 )
Norm@50keV  : 6.41497E-03    ( -0.00641487   0.00438222 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.193 for     56 degrees of freedom 
# Null hypothesis probability =   1.529739e-01
 
Photon flux (15-150 keV)    in 16.64 sec: 0.758289 ( -0.063034  0.062302 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.05464e-06 ( -9.64005e-08  9.95971e-08 ) ergs/cm2
 
Band function
 
 
Spectral model in the Band function:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
alpha       : -1.02120   ( 1.02128   1.02128 )
beta        : -1.27144    ( -0.149721   0.150486 )
Epeak [keV] : 43.4118      ( -43.3769 -43.3769 )
Norm@50keV   : 1.19554E-02    ( -0.00607497   0.925442 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          66.80 using 59 PHA bins.
# Reduced chi-squared =          1.215 for     55 degrees of freedom 
# Null hypothesis probability =   1.322636e-01
 
Photon flux (15-150 keV)    in 16.64 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)  = 2.32e-07
S(50-100 keV) = 3.84e-07
 T90 vs. Hardness ratio plot 
 
T90                                   = 15.0959999859333 sec.
Hardness ratio (energy fluence ratio) = 1.65517
 Color vs. Color plot 
 
Count Ratio  (25-50 keV) / (15-25 keV) = 1.4186
Count Ratio (50-100 keV) / (15-25 keV) = 1.31952
 Mask shadow pattern 
 
IMX = -1.822349757174955E-01, IMY = -5.798109609086134E-01
 TIME vs. PHA plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
 TIME vs. DetID plot around the trigger time 
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
 100 us light curve (15-350 keV)
 
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 0.512000
 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:
-299.227410 -0.672000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5503 -40.5555    1.1  28.9  -80.1   3.4765  10.6    1.0	Vela X-1                      
170.3005 -60.6568    0.9   0.8  165.8   2.9838  12.8    2.1	Cen X-3                       
186.8885 -62.6248    3.1   8.4  100.3   0.8204   3.7   10.8	GX 301-2                      
301.8303 -72.6110    3.5  43.5  144.8   2.0913   3.3 ------	UNKNOWN                       
186.6590 -54.3434    2.9  10.4   49.1   0.9035   3.9 ------	UNKNOWN                       
 52.7719 -73.2096    2.9  40.5 -173.0   1.4213   4.1 ------	UNKNOWN                       
 27.4030 -61.2813    3.2  55.6 -175.6   3.5129   3.6 ------	UNKNOWN                       
128.7580 -48.6088    5.4  26.2  -99.6   0.7236   2.1 ------	UNKNOWN                       
 Pre-slew background subtracted image of 15-350 keV band 
Time interval of the image:
-0.672000 15.972000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.7080 -40.6297    4.7  28.8  -79.9  -0.1589  -2.5    9.3	Vela X-1                      
170.3009 -60.4647   14.8   0.6  166.3   0.0349   0.8    9.5	Cen X-3                       
186.3328 -62.7229    5.5   8.2  101.4   0.0982   2.1    9.3	GX 301-2                      
237.6684 -62.0455    0.6  31.3  107.4   1.6283  19.2 ------	UNKNOWN                       
 78.3178 -75.1230    2.4  33.8 -168.7   0.2657   4.8 ------	UNKNOWN                       
135.2435 -24.5822    1.9  42.8  -66.5   1.0832   6.1 ------	UNKNOWN                       
 Post-slew image of 15-350 keV band 
Time interval of the image:
1307.272590 1389.742600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
170.2844 -60.6769    3.9  30.8  -75.7   0.4616   3.0    3.4	Cen X-3                       
187.0053 -62.6356    0.0  22.9  -71.6   0.0449   0.4   12.5	GX 301-2                      
255.8687 -37.7418    7.1  26.8   75.9   0.2227   1.6    8.3	4U 1700-377                   
256.2658 -36.4673    5.0  28.1   75.6   0.3327   2.3    8.6	GX 349+2                      
264.5682 -44.3920   10.5  23.6   96.6   0.1332   1.1    8.3	4U 1735-44                    
275.8636 -30.3524    4.3  40.2   98.4   1.0996   2.7    3.3	H1820-303                     
262.7919 -33.8681    7.7  32.4   83.8   0.2915   1.5   10.0	GX 354-0                      
283.8861 -57.0048    2.5  23.5  141.3   0.4832   4.6 ------	UNKNOWN                       
  1.8708 -52.7524    3.1  57.1 -174.1   1.6574   3.7 ------	UNKNOWN                       
  4.7983 -52.1929    2.7  58.4 -172.5   2.3989   4.3 ------	UNKNOWN                       
Plot creation:
Sun May 31 07:12:44 EDT 2015