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