Email from Jim:

Date: Thu, 07 Oct 2004 20:32:24 -0500
From: Jim Birchall 
To: Juliette Mammei , Roger Carlini ,
     Klaus Grimm , Mark Pitt ,
     Neven Simicevic , Greg Smith ,
     Allena Opper , Tony Forest ,
     Norman Morgan , Mike Finn ,
     David Armstrong , Yongguang Liang ,
     Shelley Page , Dave Mack ,
     Richard Jones 
Subject: Last fling with the 10-8-22 Boston collimator

To add to what I reported today, I set an additional cut on the lower 
edge of a bar that is tilted downward at 5.7 degrees and using the 
10-8-22 Boston collimator. The attached figure shows the left half of 
the moustache (not trimmed) and the right half, which corresponds to 
events falling on a tilted bar 15 cm wide. You can see a notch in the 
centre of the plot on the lower side of the right-hand part of the 
moustache where the cut is. The cut on the lower side removes 5 MHz of 
events out of 585 MHz. Average Q^2 is still 0.03 and figure of merit 
0.52.

The bar spans the region:
r = 320 cm at centre to r = 310 cm at end and r = 305 cm at centre to r 
= 295 cm at end and has cuts at 0 and +105 cm from the centre.

To summarize:
Horizontal bar, 302 < r < 318 cm, -105 < y < +105: rate = 614 MHz, Q^2 
= 0.0304, FOM = 0.57, inelastics 0.44%
V-shaped bar, 15 cm wide: rate = 580 MHz, Q^2 = 0.0300, FOM = 0.52, 
inelastics = 0.02%

Now I'll see if I can map out the inelastic/elastic ratio with Neven's 
collimator.

Jim



Jim's attachments:
cut_moustache_scatter.pdf