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Archived Messages for CLAS_OFFLINE@cebaf.gov: New EC maps

New EC maps

Lee Cole Smith (cole@apollo.phys.Virginia.EDU)
Mon, 26 Jan 1998 18:31:13 -0500

Around 18:05 today (Jan 26) I updated $CLAS_PARMS/Maps/EC_GAIN.map with
PMT gains based on cosmic ray runs performed just after the
e1 run. These take effect at run 7400.

I also updated ec_atten.dat, which is the EC scintillator attenuation length
database used by GSIM. For strips 1-8 in each of the 39 layers/sector, I replaced
measured attenuation lengths with extrapolations based on the overall trend for
that layer. Measurements for these short strips were either non-existent or had
very large errors, and previous extrapolations were somewhat arbitrary.

This required updating EC_ATTEN.map, which contains the stack attenuation
lengths required by RECSIS/EC, with values for stacks 1-8 calculated from the
new database (basically the average over the 5(8) scintillators/stack viewed by
inner(outer) PMTs).

Cole Smith
cole@apollo.phys.virginia.edu