Further Analysis of GRB ML0001:

I have modified my untriggered burst search code to look for single GRBs of known start time and relatively unknow direction.

In the process I have confirmed what Julie and Isabel presented at the collaboration meeting and I have also found something else that is very interesting.

I use a square bin, the original bin size was chosen to have the same area as the round bin used by Julie.

The square bin has dimensions 2.8 x 2.8/cos(DEC).  I search on a 0.1 x 0.1 degree map

The first plot shows the number of signal versus RA and DEC. (The background has been subtracted).

Next is the Probability Map (-Log10 Prob vs. RA and DEC).

Then I opened up the angular bin to minimize the probability.  Below is a map of the actual events in the sky.

I then searched in time around the time of the burst.  My original search was +- 100 seconds in 8 second bins.

Below I show the results for +- 1000 seconds around the burst time.

The second burst starts 32 seconds after the original start time and also lasts for 8 seconds.

The probability (pretrial is 17 events with 5.1 expected ~ 2x10-5).

Below I show the distribution of events on the sky for the second burst and then for the two time periods together.

I have also made some maps using Gaussian weighting.  There is no background subtraction here.  I used the weights based on the DELANGLE stuff Andy showed at the meeting.

PDF File for original burst.  This is a color plot.

PDF File for second burst.  This is a color plot.

PDF file for sum of bursts.  This is a color lego plot.

Below I list all the events in the two bursts.

 NEVT JD Time RA DEC NFIT XCORE YCORE 271874 555 50015.55 290.99 54.28 75 -700 -2500 271995 555 50016 291.4 52.99 14 1300 400 272103 555 50016.36 289.01 55 49 -100 -1100 272290 555 50017.08 290.47 54.83 72 -900 -1000 272346 555 50017.27 291.84 55.18 43 1000 1100 272474 555 50017.68 293.64 53.99 109 1800 -500 272515 555 50017.81 290.97 53 40 1600 -200 272555 555 50017.94 290.07 53.62 55 900 -2200 272591 555 50018.1 290.97 55.28 66 500 -800 272625 555 50018.19 291.78 52.94 34 200 500 272828 555 50018.96 288.34 52.83 32 -500 -2800 272904 555 50019.2 290.05 53.37 30 700 -500 272916 555 50019.25 291.25 54.68 36 600 2300 273205 555 50020.27 292.14 54.75 53 900 1900 273334 555 50020.81 292.29 54.37 34 -200 -1900 273343 555 50020.85 292.46 52.59 32 -200 2100 273359 555 50020.92 290.87 55.49 34 400 3200 273413 555 50021.1 289.09 53.05 73 -700 1300 273598 555 50021.81 289.55 52.94 22 -900 1200 273708 555 50022.21 289.13 52.48 157 1400 -1400 274056 555 50023.43 289.4 54.77 65 -1200 1000 274063 555 50023.47 290.48 55.3 91 -200 -400 280729 555 50047.62 290.73 55.02 62 1300 300 280767 555 50047.75 290.29 55.12 21 -1100 100 280849 555 50048.03 291.48 53.75 123 700 2200 281038 555 50048.68 288.44 53.04 65 0 700 281066 555 50048.76 289.69 54.31 35 1800 -600 281151 555 50049.11 289.51 55.55 31 -700 500 281361 555 50049.91 293.5 55.2 145 -1300 1600 281367 555 50049.94 290.41 54 82 -100 -400 281640 555 50050.91 288.87 52.84 89 2200 -1000 281716 555 50051.17 288.6 52.63 45 200 700 281831 555 50051.67 293.06 52.49 31 800 -200 281846 555 50051.73 288.71 55.78 41 100 1900 282026 555 50052.36 289.06 55.24 117 1100 1500 282343 555 50053.52 290.28 52.36 27 -1200 1400 282679 555 50054.78 293.64 55.29 112 -400 -1900 282718 555 50054.91 290.26 55.54 48 100 -2800 282799 555 50055.21 292.58 54 135 1300 1200