Minutes of HERA Meeting      20.11.2001

HERA

• It took 3 days to recover from the power failure last week. There were lots of problems with the cooling system, filters (power supplies, klystrons, cavities and some magnets) blocked by granules from the ion exchanger.
• The positron beam based alignment studies gave no consistent results. (The main goal was to determine magnet offsets and to make adjustments during the access.)
• The bridges (magnet support girders) in the south hall were moved up by up to 1.5mm.
• The clearance of the bridges and GO/GG magnets will be checked during the access to be prepared for bridge movements with beam.
• The GO and GG magnets were warmed up yesterday (will be cooled down tomorrow), NEG pumps were activated. The vacuum should be much better after the access.

HERA B

• Nobody was informed about the cooling water failure during after power outage last week. This should be improved.
• The magnet power supply will be tested tomorrow. Magnet will be turned on Thursday and will stay on. Adjustments of collimator position should be done with magnet turned on (there is a small beam offset).
• Will do target studies at 1.5MHz once the proton machine is up again.

HERMES

• The detector was turned on last week (15.11.2001). The background conditions were acceptable.

ZEUS

• There was a power cut yesterday when the emergency switches were tested, which has caused serious problems and has delayed the work on the detector.
• Requested closing of F/RCAL to check data transmission to HERA and the affect on the positron beam.
• Inner detector will be ready to be turned on on Friday. This was delayed due to the power failure.

H1

• The forward Si detector has a water leak and cannot be operated at present.
• All other detector components are commissioned.

Schedule

• Present access: Tunnel interlocks will be set tonight or tomorrow morning, key access possible until tomorrow noon, detector interlocks set until 22:00hrs tomorrow.
• HERA will start with proton beam operation.
• Proton beam for HERA B target operation, halo muon run for other experiments.
• Turn on electron machine, reestablish beam orbits after bridge movements, optimize backgrounds.
• Christmas shutdown: end of beam operation Friday, 21.12.2001 07:00hrs, interlocks set and startup machine operation 16.01.2002.

• H1 is the coordinating experiment.

                Uwe Schneekloth