Minutes of HERA Meeting      28.05.2002

HERA

• Last week recovered from venting of south interaction region. On Thursday the pressure was down to 10**-7 mbar (south IP) at 20mA.
• Very large positron beam coupling was observed on Saturday. Several problems with one of the GJ magnets in the north IR were discovered (cables and temperature sensors not connected properly and one quadrant without cooling).
• Sunday to Monday night the positron background was optimized for H1, good conditions were achieved. The beam orbit had to be moved ring inward upstream of the IP. Vertically, the beam orbit was flat with 1mm.
• Machine studies were performed yesterday and last night. The magnet positions in the north and south IRs were verified using beam based alignment measurements.

H1

• The positron beam background was reduced to a low level (Ie=11mA), see details.
• The next step is to repeat the beam optimization at about 20mA, and to go to collisions.

ZEUS

• No background optimization done so far. The detector is ready.

HERMES

• Used 12GeV beam for alignment studies. Data was taken at 27.5GeV for commissioning and timing studies. The collimator C2 position has to be optimized.

HERA B

• Got 3 night shifts of stable proton beam.

Schedule

• Continue with machine shifts until tomorrow morning.
• Concentrate on optimizing ZEUS positron background for next 3 days. Will start with 2mA (wide bunch spacing).
• Some stable beam for HERA B and HERMES on the weekend.
• The weekend schedule will be discussed on Friday 15:00hrs.
• The access on Tuesday will start at 6:00hrs. The tunnel interlock will be set Wednesday at 12:00hrs, experimental interlocks until 15:00hrs. Beam operation will start around 18:00hrs.
  

• The next scheduled maintenance days are 2.7.2002, 6.8.2002, 27.8.2002, 1.10.2002 and 5.11.2002
  

• ZEUS is the coordinating experiments.

                Uwe Schneekloth