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Presents a list of all relevant counting rates in the M2 beam, including (commented) EXPT scalers, TRIGGERs and ionisation chambers. Also shows the collimator and scraper settings, as well as the target head, absorber positions. Below 140 GeV/c only 7 absorber modules are used, at higher energies all 9 modules should be in.
Of special importance are the MIB current polarities (positive for negative beam and vice versa).
The first four wire chambers should normally be out of the beam to reduce radiation damage. They are moved out by typing the Nodal command TUNE / SPECIAL / CHAMBERS
Look for magnet currents not on BIM.0 as well as settings marked with an 'F', indicating that the BIM.0 does not correspond to the beam file loaded.
All wire chamber profiles should be more or less centred. Adjust according to the tuning procedure, chapter 4 in the M2 handbook.
Note that Collimators 2 and 4 are closed rather tightly around the beam axis at that position. This beam position may vary with the vertical angle of the primary beam on T6. If necessary, scan EXPT1 (i.e. H5 beam rate) vs COLL-2 and center the C2 and C4 slits around the maximum found. COLL-5 is the momentum slit for the hadron beam (slit about 10 mm), wide open for the muon beam.
The rate is modified by COLL-1 and 3. Equal slits for both of them.
Last updated : 12 September 2000 by Lau Gatignon