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
275.8715 -23.6671 0.0056 26.7661 145.9096 3.5045242 34.098 TRIG_00506070
Foreground time interval of the image:
-17.692 12.853 (delta_t = 30.545 [sec])
Background time interval of the image:
-90.947 -17.692 (delta_t = 73.255 [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)
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 -17.692 sec. to 17.592 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.72544 ( -0.0800795 0.0808684 )
Norm@50keV : 6.33391E-03 ( -0.000292197 0.000290962 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.87 using 59 PHA bins.
# Reduced chi-squared = 1.261 for 57 degrees of freedom
# Null hypothesis probability = 8.877223e-02
Photon flux (15-150 keV) in 35.28 sec: 0.848829 ( -0.0381793 0.0382542 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.06512e-06 ( -9.92479e-08 9.98114e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -17.692 sec. to 17.592 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.932667 ( -0.401157 0.366054 )
Epeak [keV] : 63.7034 ( -8.09739 16.3854 )
Norm@50keV : 1.63147E-02 ( -0.00568675 0.0099153 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.81 using 59 PHA bins.
# Reduced chi-squared = 1.014 for 56 degrees of freedom
# Null hypothesis probability = 4.447187e-01
Photon flux (15-150 keV) in 35.28 sec: 0.808199 ( -0.041863 0.041992 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.91786e-06 ( -1.17006e-07 1.18308e-07 ) ergs/cm2
Band function
Time interval is from -17.692 sec. to 17.592 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.932596 ( -0.309516 0.3854 )
beta : -10.0000 ( 10 3.55271e-15 )
Epeak [keV] : 63.6908 ( -7.08962 16.3813 )
Norm@50keV : 1.63151E-02 ( -0.00569578 0.00992825 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.81 using 59 PHA bins.
# Reduced chi-squared = 1.033 for 55 degrees of freedom
# Null hypothesis probability = 4.074876e-01
Photon flux (15-150 keV) in 35.28 sec: 0.810592 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93994e-06 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 12.7709 ( )
R^2/D10^2 : 0.161165 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 122.28 using 59 PHA bins.
# Reduced chi-squared = 2.1453 for 57 degrees of freedom
# Null hypothesis probability = 1.153999e-06
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.967e-07 1.568e-08
25- 50 6.644e-07 3.528e-08
50-150 6.779e-07 6.562e-08
15-150 1.539e-06 7.903e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 114.058 (-17.6902 31.5213)
Norm : 3.66753 (-0.233288 0.200174)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.44 using 59 PHA bins.
# Reduced chi-squared = 1.043 for 57 degrees of freedom
# Null hypothesis probability = 3.869293e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.376e-07 2.729e-08
25- 50 5.986e-07 3.510e-08
50-150 1.041e-06 2.829e-07
15-150 1.978e-06 3.006e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.86550 (-1.3464 1.29582)
R1^2/D10^2 : 0.619306 (-0.220745 0.466227)
kT2 [keV] : 23.7322 (-4.5261 7.90262)
R2^2/D10^2 : 1.10796E-02 (-0.00738326 0.0109911)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.20 using 59 PHA bins.
# Reduced chi-squared = 1.040 for 55 degrees of freedom
# Null hypothesis probability = 3.935382e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.806e-07 4.359e-08
25- 50 6.269e-07 1.118e-07
50-150 1.013e-06 3.369e-07
15-150 1.920e-06 4.556e-07
Peak spectrum fit
Power-law model
Time interval is from -1.464 sec. to -0.464 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.70637 ( -0.158409 0.162656 )
Norm@50keV : 1.82041E-02 ( -0.00184915 0.00182709 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.02 using 59 PHA bins.
# Reduced chi-squared = 1.141 for 57 degrees of freedom
# Null hypothesis probability = 2.175120e-01
Photon flux (15-150 keV) in 1 sec: 2.42310 ( -0.223874 0.224034 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.68465e-07 ( -1.78342e-08 1.80743e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.464 sec. to -0.464 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.904608 ( -0.795597 0.666636 )
Epeak [keV] : 62.1412 ( -13.4945 76.8419 )
Norm@50keV : 4.95835E-02 ( -0.0276122 0.083864 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.68 using 59 PHA bins.
# Reduced chi-squared = 1.084 for 56 degrees of freedom
# Null hypothesis probability = 3.110134e-01
Photon flux (15-150 keV) in 1 sec: 2.34457 ( -0.23275 0.23283 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56799e-07 ( -1.9784e-08 2.0357e-08 ) ergs/cm2
Band function
Time interval is from -1.464 sec. to -0.464 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.904554 ( -0.531782 0.929643 )
beta : -10.0000 ( 10 3.55271e-15 )
Epeak [keV] : 62.1287 ( -12.8193 76.8386 )
Norm@50keV : 4.95845E-02 ( -0.0276109 0.0837895 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.68 using 59 PHA bins.
# Reduced chi-squared = 1.103 for 55 degrees of freedom
# Null hypothesis probability = 2.786198e-01
Photon flux (15-150 keV) in 1 sec: 2.35719 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.618e-07 ( -1.61793e-07 -1.9185e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 12.2338 (-1.28715 1.46553)
R^2/D10^2 : 0.555491 (-0.188943 0.2805)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 78.35 using 59 PHA bins.
# Reduced chi-squared = 1.375 for 57 degrees of freedom
# Null hypothesis probability = 3.185513e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.761e-08 2.880e-09
25- 50 5.668e-08 6.135e-09
50-150 5.166e-08 1.074e-08
15-150 1.259e-07 1.435e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 122.995 (-38.3446 67.9797)
Norm : 10.2632 (-1.13054 1.4235)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.51 using 59 PHA bins.
# Reduced chi-squared = 1.079 for 57 degrees of freedom
# Null hypothesis probability = 3.178736e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.670e-08 3.225e-09
25- 50 4.798e-08 6.360e-09
50-150 8.666e-08 3.764e-08
15-150 1.613e-07 4.285e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.92033 (-2.20587 2.44035)
R1^2/D10^2 : 2.73209 (-1.61663 6.97349)
kT2 [keV] : 21.3417 (-5.70103 15.3193)
R2^2/D10^2 : 5.11658E-02 (-0.0445341 0.136343)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.20 using 59 PHA bins.
# Reduced chi-squared = 1.095 for 55 degrees of freedom
# Null hypothesis probability = 2.930264e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.514e-08 1.166e-08
25- 50 5.051e-08 1.879e-08
50-150 8.157e-08 4.433e-08
15-150 1.572e-07 7.006e-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: 1.70396 ( -0.0766365 0.0773607 )
Norm@50keV : 7.17286E-03 ( -0.00031702 0.000315779 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.42 using 59 PHA bins.
# Reduced chi-squared = 1.253 for 57 degrees of freedom
# Null hypothesis probability = 9.476280e-02
Photon flux (15-150 keV) in 30.54 sec: 0.953963 ( -0.0415057 0.0415852 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.02758e-06 ( -9.37941e-08 9.4281e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.876144 ( -0.380085 0.349111 )
Epeak [keV] : 64.7391 ( -7.76794 14.6116 )
Norm@50keV : 1.91541E-02 ( -0.00639297 0.0107735 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.16 using 59 PHA bins.
# Reduced chi-squared = 0.9493 for 56 degrees of freedom
# Null hypothesis probability = 5.829798e-01
Photon flux (15-150 keV) in 30.54 sec: 0.906814 ( -0.045225 0.045368 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.88067e-06 ( -1.09196e-07 1.10381e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.876068 ( -0.259759 0.475211 )
beta : -10.0000 ( 10 3.55271e-15 )
Epeak [keV] : 64.7259 ( -7.76701 14.6102 )
Norm@50keV : 1.91550E-02 ( -0.00640147 0.0107852 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.16 using 59 PHA bins.
# Reduced chi-squared = 0.9666 for 55 degrees of freedom
# Null hypothesis probability = 5.451714e-01
Photon flux (15-150 keV) in 30.54 sec: 0.911852 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.90252e-06 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 5.65e-07
S(50-100 keV) = 6.83e-07
T90 vs. Hardness ratio plot
T90 = 22.8199999928474 sec.
Hardness ratio (energy fluence ratio) = 1.20885
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.41067
Count Ratio (50-100 keV) / (15-25 keV) = 0.82212
Mask shadow pattern
IMX = -4.177162113801573E-01, IMY = -2.827130661494183E-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:
-90.947410 -17.692000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9799 -15.6363 0.5 15.2 -125.8 2.6745 22.2 0.2 Sco X-1
254.2928 35.4181 7.1 40.4 7.5 -0.3167 -1.6 9.3 Her X-1
256.1081 -37.6793 0.0 32.7 -170.5 0.0521 0.3 11.4 4U 1700-377
256.2660 -36.3971 8.0 31.4 -170.8 0.2146 1.4 8.3 GX 349+2
263.1290 -24.5691 0.0 20.8 171.1 -0.1462 -1.1 12.4 GX 1+4
264.9482 -44.5689 0.0 40.4 179.8 0.1322 0.6 11.3 4U 1735-44
268.4496 -1.5226 6.2 12.9 84.6 0.2461 1.8 6.5 SW J1753.5-0127
270.1277 -25.0788 10.1 24.3 157.1 -0.1597 -1.1 8.5 GX 5-1
270.4532 -25.7328 10.8 25.0 157.4 0.1552 1.1 8.2 GRS 1758-258
273.8852 -14.2038 5.9 19.9 128.6 -0.2729 -2.0 12.3 GX 17+2
276.0905 -30.4031 22.5 31.7 155.3 0.0918 0.5 8.8 H1820-303
284.9022 -25.0045 12.8 34.2 138.5 -0.2063 -0.9 8.9 HT1900.1-2455
288.8648 10.9537 9.1 36.4 73.6 -0.4469 -1.3 3.9 GRS 1915+105
262.9233 -33.8455 5.0 29.6 177.9 0.3325 2.3 3.3 GX 354-0
276.0843 31.8441 3.4 41.5 35.8 0.8993 3.4 ------ UNKNOWN
232.6684 38.9634 2.1 48.9 -14.4 1.3782 5.4 ------ UNKNOWN
213.1725 19.6776 3.3 48.8 -48.6 2.3275 3.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-17.692000 12.852580
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
245.0054 -15.4897 14.5 15.1 -125.4 -0.0676 -0.8 9.2 Sco X-1
254.6371 35.2126 0.0 40.2 7.9 -0.0449 -0.3 11.7 Her X-1
256.1365 -37.9782 5.6 33.0 -170.5 0.2000 2.1 10.7 4U 1700-377
256.4991 -36.3826 9.9 31.4 -171.1 0.1114 1.2 3.9 GX 349+2
263.1914 -24.8634 0.0 21.1 171.2 0.1735 2.0 12.2 GX 1+4
264.6835 -44.5028 25.2 40.3 -179.9 -0.0577 -0.5 4.1 4U 1735-44
268.5229 -1.4651 5.8 13.0 84.4 -0.1750 -2.0 9.3 SW J1753.5-0127
270.4196 -24.9855 15.7 24.3 156.4 0.0658 0.7 9.3 GX 5-1
270.2947 -25.7354 4.6 24.9 157.7 0.2256 2.5 0.6 GRS 1758-258
273.8875 -14.2151 0.0 19.9 128.6 0.1415 1.5 12.7 GX 17+2
275.9301 -30.3766 1399.6 31.6 155.5 -0.0010 -0.0 0.6 H1820-303
285.0577 -24.8391 21.1 34.2 138.1 0.0772 0.5 5.0 HT1900.1-2455
288.9256 11.0783 0.0 36.5 73.4 -0.1503 -0.7 10.9 GRS 1915+105
263.1705 -33.9525 273.4 29.7 177.6 -0.0039 -0.0 11.5 GX 354-0
275.8715 -23.6671 0.3 26.8 145.9 3.5056 34.1 ------ UNKNOWN
265.0294 -55.7953 2.4 51.3 -176.8 1.0029 4.8 ------ UNKNOWN
214.0132 7.5224 2.6 43.7 -64.0 1.5668 4.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
62.452580 962.582000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
244.9815 -15.6409 0.4 30.1 -77.9 30.7569 32.0 0.1 Sco X-1
255.8236 -37.6748 0.0 22.1 -131.6 0.3615 0.6 12.8 4U 1700-377
256.3770 -36.4866 2.7 21.1 -129.5 2.6723 4.2 4.7 GX 349+2
262.8520 -24.5934 17.7 11.9 -94.8 0.4280 0.7 12.5 GX 1+4
264.8711 -44.3649 2.8 22.6 -156.8 2.5701 4.1 7.5 4U 1735-44
268.3597 -1.4376 2.8 23.4 -16.8 2.4635 4.2 1.0 SW J1753.5-0127
270.4089 -25.0826 4.2 5.2 -104.8 1.6880 2.8 6.8 GX 5-1
270.3364 -25.7461 3.5 5.4 -111.4 2.0629 3.4 1.8 GRS 1758-258
274.0711 -14.0471 3.5 9.8 -7.9 2.1445 3.3 3.9 GX 17+2
275.9640 -30.3358 2.5 6.7 -178.3 2.6939 4.6 2.8 H1820-303
285.0340 -24.9199 39.4 8.4 102.9 -0.1846 -0.3 0.1 HT1900.1-2455
288.8039 11.0215 4.5 36.9 23.9 2.5668 2.5 4.6 GRS 1915+105
262.9250 -33.8098 2.2 15.2 -132.4 2.9800 5.3 3.5 GX 354-0
327.4935 -52.5729 3.7 48.4 142.8 9.7641 3.1 ------ UNKNOWN
271.8947 8.6343 4.4 32.5 -4.9 2.0476 2.6 ------ UNKNOWN
265.8207 -80.5282 3.8 57.0 -175.6 10.2972 3.0 ------ UNKNOWN
255.2399 -41.6542 1.2 24.9 -138.9 6.1754 9.6 ------ UNKNOWN
Plot creation:
Sat May 30 21:20:39 EDT 2015