Markarian 501 Search Update
(Another Preliminary Work for Collaborators Only!)
4 Feb 1998
The Result:

Nearly all the data collected from turn on (Feb 8,1997) through August 1997
has been stipped from the Milagrito raw data.  In total, 197 tapes were processed.
The stripped Markarian 501 data occupies 14 high density DLT tapes (~400Gb).
The data from the dec band can be reprocessed in as little as 4-5 days. With more
CPU it could be reprocessed in as little as 30 hours with a single drive head. Compare
this to the 2 months it took to extract the data from the raw Milagrito data.

I present here the entire dataset. I have choosen to use the Goodman method of
presenting results: show every plot and let the viewer draw their own conclusions.

The below data were reconstructed with our standard offline software with a
4ns/100m curvature correction. There was a cut on events with zenith angle >45 deg
and events with less than 20 tubes in the angle fit. In the previous update, results with
a 40 tube cut were presented. Don't get all apples and oranges on me, the 40 tube
results will be presented too.

Significance maps for NFIT>20 and bin sizes from 0.5-2.5 deg:
 all20_1all20_2all20_3all20_4all20_5

The next set of plots are the signal maps (background not subtracted):
 all20ev_1all20ev_2all20ev_3all20ev_4all20ev_5
It appears that a signal is visible even with no background subtraction
in the small bin data. Furthermore, there is little evidence of a systematic shift.

Significance maps for NFIT>40:
 all40_1all40_2all40_3all40_4all40_5

And now the signal maps for NFIT>40:
 all40ev_1all40ev_2all40ev_3all40ev_4all40ev_5

Note that I have plotted here the coordinates of Mrk 501 minus the coordinates
of the event, so offsets in the positive direction represent source position
measurements in the negative direction.

To clarify, a 0.5 deg bin is a bin with a total diameter of .5 deg.
 

-Cheers Andy