1. Preliminary Results from Structured Beam Test CMS Trigger Meeting June 3, 2003 Brian Mohr UCLA Dept. of Physics

2. Expect muons in 48 out of 924 bx due to beam structure Verified here by CLCT bxn from data

3. Relative position of key half strip from CLCTs from chamber 2 vs. Chamber 1 Note: Chamber 1 is vertically higher than Chamber 2 (thus the offset in position).

4. Scan over ALCT delay chip settings Efficiency defined as number of events in maximum bin divided by total number of events.

5. Approximately optimal timing settings for: –Cathodes: Bxn at TMB L1A - Bxn at CLCT (above) –Anodes: Bxn at ALCT L1A - Bxn at ALCT (below)

6. Acknowledgements Special Thanks to: –Slava Valuev –Jason Mumford for producing the preceding plots: Based on code from Caltech, Florida, Rice, Los Angeles Thanks also to participants in beam test: –Darin Acosta, Jason Gilmore, Jianhui Gu, Misha Ignatenko, Pat Murray, Greg Pawloski, Jay Roberts –others not listed here