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
276.1951 37.6025 0.0042 17.9957 -34.0834 1.7417863 46.281 TRIG_00176818
Foreground time interval of the image:
-0.652 10.029 (delta_t = 10.681 [sec])
Background time interval of the image:
-299.072 -0.652 (delta_t = 298.420 [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 -0.652 sec. to 17.576 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.62126 ( -0.0643743 0.0647158 )
Norm@50keV : 7.50084E-03 ( -0.000277474 0.000276868 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.41 using 59 PHA bins.
# Reduced chi-squared = 1.112 for 57 degrees of freedom
# Null hypothesis probability = 2.607037e-01
Photon flux (15-150 keV) in 18.23 sec: 0.970352 ( -0.0362263 0.0362822 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.27563e-06 ( -5.02242e-08 5.0414e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.652 sec. to 17.576 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.881577 ( -0.30215 0.282746 )
Epeak [keV] : 73.8796 ( -9.11195 16.9346 )
Norm@50keV : 1.78009E-02 ( -0.00491235 0.00738219 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.34 using 59 PHA bins.
# Reduced chi-squared = 0.7381 for 56 degrees of freedom
# Null hypothesis probability = 9.285129e-01
Photon flux (15-150 keV) in 18.23 sec: 0.929336 ( -0.038973 0.039042 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.19737e-06 ( -5.76269e-08 5.79131e-08 ) ergs/cm2
Band function
Time interval is from -0.652 sec. to 17.576 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.11535 ( -2.49145 3.47311 )
beta : -1.84522 ( 1.83818 0.113997 )
Epeak [keV] : 37.6002 ( -5.24208 32.2267 )
Norm@50keV : 0.412293 ( -0.409881 127.572 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.92 using 59 PHA bins.
# Reduced chi-squared = 0.7076 for 55 degrees of freedom
# Null hypothesis probability = 9.504935e-01
Photon flux (15-150 keV) in 18.23 sec: 0.928267 ( 6.07173 -0.038922 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.40401e-15 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.9190 ( )
R^2/D10^2 : 0.138221 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 150.76 using 59 PHA bins.
# Reduced chi-squared = 2.6450 for 57 degrees of freedom
# Null hypothesis probability = 2.092630e-10
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.032e-07 6.645e-09
25- 50 3.815e-07 1.695e-08
50-150 4.852e-07 3.518e-08
15-150 9.699e-07 4.166e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 160.478 (-28.7209 32.5644)
Norm : 3.97335 (-0.160454 0.193431)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.49 using 59 PHA bins.
# Reduced chi-squared = 0.8156 for 57 degrees of freedom
# Null hypothesis probability = 8.385876e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.849e-07 1.199e-08
25- 50 3.460e-07 2.570e-08
50-150 7.018e-07 1.814e-07
15-150 1.233e-06 2.082e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.25581 (-0.915932 1.00939)
R1^2/D10^2 : 0.852356 (-0.280539 0.466499)
kT2 [keV] : 22.8226 (-2.65373 3.85184)
R2^2/D10^2 : 1.73439E-02 (-0.00797822 0.0112591)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.21 using 59 PHA bins.
# Reduced chi-squared = 0.6583 for 55 degrees of freedom
# Null hypothesis probability = 9.763853e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.662e-07 2.021e-08
25- 50 3.616e-07 3.883e-08
50-150 6.674e-07 1.185e-07
15-150 1.195e-06 1.612e-07
Peak spectrum fit
Power-law model
Time interval is from 4.312 sec. to 5.312 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37543 ( -0.129848 0.130281 )
Norm@50keV : 1.45642E-02 ( -0.00116344 0.00116075 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.85 using 59 PHA bins.
# Reduced chi-squared = 0.9446 for 57 degrees of freedom
# Null hypothesis probability = 5.941915e-01
Photon flux (15-150 keV) in 1 sec: 1.76401 ( -0.140245 0.140344 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.41454e-07 ( -1.25641e-08 1.26615e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.312 sec. to 5.312 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.522307 ( -0.661791 0.569944 )
Epeak [keV] : 86.0074 ( -18.9695 71.902 )
Norm@50keV : 3.95963E-02 ( -0.0189837 0.04493 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.90 using 59 PHA bins.
# Reduced chi-squared = 0.8375 for 56 degrees of freedom
# Null hypothesis probability = 8.017045e-01
Photon flux (15-150 keV) in 1 sec: 1.71017 ( -0.1452 0.14502 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.328e-07 ( -1.3921e-08 1.4012e-08 ) ergs/cm2
Band function
Time interval is from 4.312 sec. to 5.312 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.211763 ( -0.809349 0.206543 )
beta : -1.94063 ( 1.9388 0.499019 )
Epeak [keV] : 70.3460 ( -38.5539 66.3794 )
Norm@50keV : 6.06933E-02 ( -0.0196426 133.971 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.27 using 59 PHA bins.
# Reduced chi-squared = 0.8412 for 55 degrees of freedom
# Null hypothesis probability = 7.930419e-01
Photon flux (15-150 keV) in 1 sec: 1.70847 ( 5.29153 -0.14463 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.33731e-07 ( -1.33724e-07 -1.3821e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 15.4894 (-1.39288 1.56517)
R^2/D10^2 : 0.189112 (-0.0537752 0.0731403)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.29 using 59 PHA bins.
# Reduced chi-squared = 1.145 for 57 degrees of freedom
# Null hypothesis probability = 2.108647e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.445e-09 1.304e-09
25- 50 3.863e-08 3.995e-09
50-150 6.396e-08 9.850e-09
15-150 1.120e-07 1.147e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 7.25012 (-0.573256 0.573259)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.55 using 59 PHA bins.
# Reduced chi-squared = 0.9570 for 57 degrees of freedom
# Null hypothesis probability = 5.676339e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.815e-08 1.680e-09
25- 50 3.491e-08 6.450e-09
50-150 7.656e-08 3.083e-08
15-150 1.296e-07 3.470e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.93606 (-3.09813 3.27847)
R1^2/D10^2 : 0.735815 (-0.396454 1.62394)
kT2 [keV] : 27.4375 (-8.20815 40.3109)
R2^2/D10^2 : 1.83807E-02 (-0.0170282 0.0567465)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.51 using 59 PHA bins.
# Reduced chi-squared = 0.8457 for 55 degrees of freedom
# Null hypothesis probability = 7.853986e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.368e-08 5.377e-09
25- 50 3.750e-08 1.590e-08
50-150 8.314e-08 4.064e-08
15-150 1.343e-07 5.593e-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: 1.50835 ( -0.0615194 0.0617002 )
Norm@50keV : 1.06784E-02 ( -0.000375699 0.000375362 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.11 using 59 PHA bins.
# Reduced chi-squared = 1.213 for 57 degrees of freedom
# Null hypothesis probability = 1.304224e-01
Photon flux (15-150 keV) in 10.68 sec: 1.33610 ( -0.0484469 0.0485229 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.08043e-06 ( -4.10992e-08 4.12307e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.662359 ( -0.302042 0.283001 )
Epeak [keV] : 80.4228 ( -9.3003 16.0611 )
Norm@50keV : 2.77705E-02 ( -0.00745354 0.0110318 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.78 using 59 PHA bins.
# Reduced chi-squared = 0.7103 for 56 degrees of freedom
# Null hypothesis probability = 9.502915e-01
Photon flux (15-150 keV) in 10.68 sec: 1.27282 ( -0.05209 0.0522 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.01299e-06 ( -4.65552e-08 4.66951e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.579745 ( -0.339234 0.641756 )
beta : -2.26999 ( 2.27404 0.44613 )
Epeak [keV] : 75.9793 ( -21.1901 18.3537 )
Norm@50keV : 3.09434E-02 ( -0.0100392 0.0466471 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.26 using 59 PHA bins.
# Reduced chi-squared = 0.7139 for 55 degrees of freedom
# Null hypothesis probability = 9.461214e-01
Photon flux (15-150 keV) in 10.68 sec: 1.27055 ( 5.72945 -0.05199 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.01381e-06 ( -1.01373e-06 -4.66161e-08 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 3.34e-07
S(50-100 keV) = 4.34e-07
T90 vs. Hardness ratio plot
T90 = 13.2120000123978 sec.
Hardness ratio (energy fluence ratio) = 1.2994
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.48538
Count Ratio (50-100 keV) / (15-25 keV) = 0.985722
Mask shadow pattern
IMX = 2.690370798467176E-01, IMY = 1.820379872454307E-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:
-299.072000 -0.652000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.3310 35.1879 0.0 34.0 -16.1 -0.3124 -1.2 11.2 Her X-1
288.8336 10.9480 1.8 36.2 -88.1 3.7315 6.5 2.1 GRS 1915+105
299.5871 35.1991 0.2 11.3 -111.5 13.9365 68.6 0.2 Cyg X-1
308.0550 40.8911 2.2 9.4 -160.9 1.0635 5.2 4.5 Cyg X-3
326.1285 38.4589 4.0 22.4 177.6 0.6274 2.9 8.5 Cyg X-2
317.3283 32.1986 2.5 20.8 -156.7 0.9655 4.6 ------ UNKNOWN
268.4826 11.9729 2.7 42.2 -57.7 2.8238 4.3 ------ UNKNOWN
324.7872 0.3522 2.8 51.9 -138.3 4.8418 4.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.652000 10.028600
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.3898 35.1992 25.7 34.0 -16.1 -0.0205 -0.4 9.2 Her X-1
288.9143 10.8850 11.4 36.2 -88.3 -0.0891 -1.0 7.7 GRS 1915+105
299.7305 35.3277 16.2 11.2 -112.2 0.0267 0.7 10.2 Cyg X-1
308.1111 41.0295 3.7 9.3 -161.7 0.1152 3.1 4.6 Cyg X-3
326.2214 38.3440 6.3 22.6 177.8 -0.0740 -1.8 2.7 Cyg X-2
276.1951 37.6025 0.2 18.0 -34.1 1.7418 46.3 ------ UNKNOWN
242.8969 22.5658 2.2 49.7 -21.9 0.4308 5.2 ------ UNKNOWN
236.2190 15.9283 1.9 58.8 -22.4 1.4478 6.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
54.828600 302.991400
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.4621 35.3507 92.4 17.6 16.5 -0.0216 -0.1 0.5 Her X-1
268.2952 -1.3360 6.3 39.6 -60.3 0.8829 1.8 8.2 SW J1753.5-0127
288.7988 10.9677 1.0 28.9 -99.0 3.4256 12.1 1.3 GRS 1915+105
299.5860 35.1937 0.2 18.9 -162.5 11.2391 66.4 0.5 Cyg X-1
308.1127 40.9461 3.2 24.8 179.5 0.7006 3.7 0.4 Cyg X-3
325.9715 38.2417 7.6 38.8 -179.5 -0.4081 -1.5 10.6 Cyg X-2
251.2310 51.9083 2.7 22.6 64.5 0.9082 4.3 ------ UNKNOWN
249.3029 36.5424 2.2 21.4 22.7 0.9277 5.2 ------ UNKNOWN
334.2533 16.9821 2.5 54.6 -157.3 2.9918 4.6 ------ UNKNOWN
270.1099 -5.6797 2.4 43.7 -64.0 3.8503 4.7 ------ UNKNOWN
Plot creation:
Sun May 31 14:39:25 EDT 2015