1J. Gu CERN CSC Meeting July 2008

DAQMB/FEBs Readiness for First Beam

Jianui GuThe Ohio State University

2J. Gu CERN CSC Meeting July 2008

Electronics - First Beam Overview

This is a Machine Run (for them and us)First Priority is to “Time In” the Electronics

Beam Will Advance in Stages: Halo Muons, Low Luminosity Collisions,… Thus timing will advance in stages…

Tools:

Greg’s Radioactive Triggers(done now)• special runs single chambers • requires rate

Shift timing all chambers take data• requires data analysis• no special software written

Cosmic Ray – Crude Timing•random arrival (anytime)•random direction (speed of light)

Colliding Beams-Precise Timing•precise arrival (3 nsec)•fixed time of flight

Data and Time will be taken for Solely Hardware Purposes

3J. Gu CERN CSC Meeting July 2008

Electronics - First Beam Overview

Improved timing should lead to: DAQ Board Readout Efficiency 100% Reduction of Board Readout Errors

Beam gives better understanding of timing and synchronization:

Test Beam 2003 –time structured beam

Time (bunch crossings)

Cathode Pulse Peak Time (avg 6 planes)

Time (nsec)

LHC Beam Structure(initial separation 75 nsec)

~5nsecdominated by electron drift

Cathode Pulse Peak Time (avg 6 planes)

4J. Gu CERN CSC Meeting July 2008

Electronics – Expected Status

Live Electronics First Beam

by next week all pc crate electronics done• bad CFEBs,ALCTs• connector, cables …

Expect no access to chamber electronicsbefore first beam

On Chamber Problems:

12 CFEBs (kill 1/5 chamber each) 9 ALCTs (kill full chamber each)

Enter run with 97% Chamber Live