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
247.8734 2.1866 0.0072 55.6708 5.6150 8.8356351 26.685 TRIG_00113120
Foreground time interval of the image:
-5.908 25.317 (delta_t = 31.225 [sec])
Background time interval of the image:
-299.784 -5.908 (delta_t = 293.876 [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
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
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 -5.908 sec. to 27.804 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38848 ( -0.075386 0.0750222 )
Norm@50keV : 2.47658E-02 ( -0.00108759 0.00108622 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.44 using 59 PHA bins.
# Reduced chi-squared = 0.9726 for 57 degrees of freedom
# Null hypothesis probability = 5.339768e-01
Photon flux (15-150 keV) in 33.71 sec: 3.00823 ( -0.146908 0.147425 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.08615e-06 ( -3.60852e-07 3.61007e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -5.908 sec. to 27.804 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.17321 ( -0.323698 0.247606 )
Epeak [keV] : 223.345 ( -100.176 -223.345 )
Norm@50keV : 3.08743E-02 ( -0.00675415 0.0117449 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.00 using 59 PHA bins.
# Reduced chi-squared = 0.9642 for 56 degrees of freedom
# Null hypothesis probability = 5.511284e-01
Photon flux (15-150 keV) in 33.71 sec: 2.97556 ( -0.15307 0.15378 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.0425e-06 ( -3.70271e-07 3.68922e-07 ) ergs/cm2
Band function
Time interval is from -5.908 sec. to 27.804 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.797942 ( -0.499478 5.6845 )
beta : -1.54109 ( 1.54111 0.165905 )
Epeak [keV] : 97.4759 ( -48.6883 249.05 )
Norm@50keV : 4.90517E-02 ( -0.0227474 0.27115 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.90 using 59 PHA bins.
# Reduced chi-squared = 0.9436 for 55 degrees of freedom
# Null hypothesis probability = 5.939359e-01
Photon flux (15-150 keV) in 33.71 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] : 18.5471 ( )
R^2/D10^2 : 0.169928 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 161.66 using 59 PHA bins.
# Reduced chi-squared = 2.8362 for 57 degrees of freedom
# Null hypothesis probability = 5.912850e-12
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.906e-07 3.573e-08
25- 50 1.847e-06 1.222e-07
50-150 4.645e-06 3.219e-07
15-150 6.882e-06 3.405e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 12.7817 (-0.559984 0.559784)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.11 using 59 PHA bins.
# Reduced chi-squared = 1.300 for 57 degrees of freedom
# Null hypothesis probability = 6.342631e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.073e-06 5.781e-08
25- 50 2.065e-06 1.094e-07
50-150 4.528e-06 2.309e-07
15-150 7.666e-06 3.826e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 10.6305 (-1.93346 1.95019)
R1^2/D10^2 : 0.804723 (-0.295535 0.62242)
kT2 [keV] : 44.4928 (-12.7469 48.0527)
R2^2/D10^2 : 6.75737E-03 (-0.00551527 0.00774135)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.20 using 59 PHA bins.
# Reduced chi-squared = 1.058 for 55 degrees of freedom
# Null hypothesis probability = 3.583286e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.895e-07 9.692e-08
25- 50 2.097e-06 2.719e-07
50-150 5.160e-06 1.709e-06
15-150 7.946e-06 1.953e-06
Peak spectrum fit
Power-law model
Time interval is from 24.272 sec. to 25.272 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.14311 ( -0.130507 0.128882 )
Norm@50keV : 0.107262 ( -0.00911817 0.00909533 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.50 using 59 PHA bins.
# Reduced chi-squared = 1.254 for 57 degrees of freedom
# Null hypothesis probability = 9.364115e-02
Photon flux (15-150 keV) in 1 sec: 12.4988 ( -1.10996 1.11333 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.10651e-06 ( -9.56281e-08 9.57241e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.272 sec. to 25.272 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 6.65530E-02 ( -0.693575 0.598546 )
Epeak [keV] : 107.979 ( -21.1666 59.3578 )
Norm@50keV : 0.312041 ( -0.136705 0.286788 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.17 using 59 PHA bins.
# Reduced chi-squared = 1.092 for 56 degrees of freedom
# Null hypothesis probability = 2.958049e-01
Photon flux (15-150 keV) in 1 sec: 12.1734 ( -1.1151 1.1211 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0988e-06 ( -9.9528e-08 9.894e-08 ) ergs/cm2
Band function
Time interval is from 24.272 sec. to 25.272 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.209136 ( -0.835188 -0.210476 )
beta : -1.84627 ( 1.84497 0.505867 )
Epeak [keV] : 91.7014 ( -44.8651 66.1007 )
Norm@50keV : 0.435657 ( -0.255635 330.19 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.87 using 59 PHA bins.
# Reduced chi-squared = 1.107 for 55 degrees of freedom
# Null hypothesis probability = 2.729120e-01
Photon flux (15-150 keV) in 1 sec: 12.0585 ( -5.0585 -1.1376 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.08799e-06 ( -1.08798e-06 -9.7975e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 21.0782 (-1.90723 2.14499)
R^2/D10^2 : 0.530892 (-0.146833 0.196439)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.80 using 59 PHA bins.
# Reduced chi-squared = 1.260 for 57 degrees of freedom
# Null hypothesis probability = 8.960786e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.449e-08 7.570e-09
25- 50 2.292e-07 2.835e-08
50-150 7.593e-07 9.425e-08
15-150 1.033e-06 1.023e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 53.1228 (-4.57862 4.57781)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 96.45 using 59 PHA bins.
# Reduced chi-squared = 1.692 for 57 degrees of freedom
# Null hypothesis probability = 8.544737e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.322e-07 1.220e-08
25- 50 2.544e-07 3.745e-08
50-150 5.579e-07 1.991e-07
15-150 9.445e-07 2.042e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 10.6270 (-5.12869 7.12927)
R1^2/D10^2 : 2.18142 (-1.38662 11.9779)
kT2 [keV] : 30.0310 (-7.43025 -30.1599)
R2^2/D10^2 : 0.126117 (-0.122415 0.259271)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.06 using 59 PHA bins.
# Reduced chi-squared = 1.110 for 55 degrees of freedom
# Null hypothesis probability = 2.672013e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.886e-08 3.793e-08
25- 50 2.478e-07 1.291e-07
50-150 7.845e-07 4.079e-07
15-150 1.101e-06 5.615e-07
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: 1.36293 ( -0.0871607 0.0865284 )
Norm@50keV : 2.11941E-02 ( -0.00108522 0.00108332 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.70 using 59 PHA bins.
# Reduced chi-squared = 1.170 for 57 degrees of freedom
# Null hypothesis probability = 1.780468e-01
Photon flux (15-150 keV) in 31.22 sec: 2.56018 ( -0.144888 0.145446 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.444e-06 ( -3.34816e-07 3.35019e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.09909 ( -0.384681 0.300281 )
Epeak [keV] : 197.442 ( -84.2461 -197.455 )
Norm@50keV : 2.78162E-02 ( -0.00718797 0.0130844 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.13 using 59 PHA bins.
# Reduced chi-squared = 1.163 for 56 degrees of freedom
# Null hypothesis probability = 1.889658e-01
Photon flux (15-150 keV) in 31.22 sec: 2.52872 ( -0.15022 0.15094 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.40022e-06 ( -3.44606e-07 3.43077e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.683360 ( -0.552657 0.677082 )
beta : -1.55751 ( 1.55433 0.199281 )
Epeak [keV] : 94.4014 ( -45.5686 180.056 )
Norm@50keV : 4.61673E-02 ( -0.0250616 6.259 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.65 using 59 PHA bins.
# Reduced chi-squared = 1.139 for 55 degrees of freedom
# Null hypothesis probability = 2.234525e-01
Photon flux (15-150 keV) in 31.22 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) = 1.89e-06
S(50-100 keV) = 2.89e-06
T90 vs. Hardness ratio plot
T90 = 32.0920000076294 sec.
Hardness ratio (energy fluence ratio) = 1.5291
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.69068
Count Ratio (50-100 keV) / (15-25 keV) = 1.67572
Mask shadow pattern
IMX = 1.457314487497005E+00, IMY = -1.432755237830371E-01
TIME vs. PHA plot around the trigger time
TIME vs. DetID plot around the trigger time
100 us light curve (15-350 keV)
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:
-299.784000 -5.908000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.5448 35.2573 8.9 53.7 -35.9 -1.2636 -1.3 6.7 Her X-1
151.8041 11.6414 2.5 41.8 165.3 1.3466 4.6 ------ UNKNOWN
137.4834 12.9771 2.6 54.6 173.1 3.2350 4.4 ------ UNKNOWN
183.1822 16.8375 3.0 11.7 148.0 0.5427 3.9 ------ UNKNOWN
224.1733 12.9728 2.5 29.9 5.1 0.8096 4.6 ------ UNKNOWN
242.5756 11.5984 4.3 47.2 -2.9 0.8371 2.7 ------ UNKNOWN
168.7902 61.8461 2.4 43.5 -114.6 3.5621 4.8 ------ UNKNOWN
161.2027 60.4952 3.1 44.8 -119.9 2.6957 3.7 ------ UNKNOWN
193.2879 63.1356 3.9 41.1 -98.2 2.6871 3.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-5.908000 25.316590
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.6236 35.3185 14.4 53.8 -35.9 -0.1995 -0.8 8.3 Her X-1
153.5100 -3.8473 2.3 47.5 144.6 0.9587 5.1 ------ UNKNOWN
247.8733 2.1866 0.5 55.7 5.6 8.8301 23.5 ------ UNKNOWN
217.5194 30.6845 2.6 22.5 -35.0 0.2369 4.5 ------ UNKNOWN
143.7368 54.6930 2.0 49.7 -133.3 1.4040 5.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
112.516600 302.320400
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9857 -15.6385 0.2 18.0 16.2 11.0520 71.8 0.4 Sco X-1
254.4404 35.3673 5.6 33.7 -163.2 -0.4122 -2.0 1.7 Her X-1
255.9869 -37.8450 165.7 40.7 -2.7 0.0176 0.1 0.1 4U 1700-377
256.4679 -36.4674 3.7 39.5 -3.7 0.7201 3.1 3.1 GX 349+2
263.0291 -24.5901 7.4 30.5 -20.7 0.2874 1.6 9.4 GX 1+4
264.6068 -44.4751 4.8 49.0 -8.6 0.8120 2.4 6.0 4U 1735-44
268.5305 -1.5718 0.0 21.0 -72.7 0.0946 0.5 12.1 SW J1753.5-0127
270.3015 -25.0984 2.7 34.9 -30.0 0.8393 4.2 1.5 GX 5-1
270.2950 -25.7206 3.6 35.3 -29.3 0.6668 3.2 1.4 GRS 1758-258
274.1235 -13.9727 6.7 30.6 -50.3 0.3824 1.7 7.8 GX 17+2
276.0191 -30.4674 5.8 42.2 -30.0 -0.5518 -2.0 7.7 H1820-303
284.9467 -24.8135 8.8 44.9 -43.6 0.5542 1.3 8.1 HT1900.1-2455
262.8444 -33.8346 6.2 38.7 -12.9 0.3855 1.9 7.2 GX 354-0
273.6578 5.2964 3.0 25.9 -90.5 0.8545 3.8 ------ UNKNOWN
264.7583 60.1315 4.5 59.4 -163.2 3.7391 2.6 ------ UNKNOWN
290.3975 -19.6874 3.2 47.1 -53.1 2.6502 3.6 ------ UNKNOWN
Plot creation:
Sun May 31 17:09:02 EDT 2015