Minutes of HERA Meeting
09.10.2001
Summary of HERA Status
Last week was mainly spent on preparing for collisions.
- There were several stable positron runs to commission the luminosity
monitors.
- Parasiticly, closed bumps were studied. There is no indication for optics errors.
- Synchronization of both beams was checked and is now locked. Small
adjustments (1ns) may still be necessary.
- The horizontal wire scanner is working. The vertical wire is broken. There
is no estimate of the emittance yet.
- First collisions in the north IP were established from Saturday to Sunday
using the beam tune signal.
- Sunday afternoon collisions were observed in the H1 luminosity monitor.
The photon position in the lumi monitor changed as expected when the beam
tilt was changed.
- The electron and synchrotron radiation collimators were moved in once. There
was no improvement of the background conditions. The vacuum in the new
straight sections is still quite poor. The NEG pumps have not been activated
yet. This is planned for the 3 day November access.
- The old bunch current measurement is still sent to the experiments via the
HIT system. The plan is to switch to the new system when stable luminosity
operation is established.
H1
- The present threshold of the luminosity monitor is set to 1 GeV. A threshold
scan will be done next.
- The absolute background rates in the main detector are acceptable. There
were no alarms from the radiation monitor.
- Daniel Pitzl is the new technical coordinator.
ZEUS
- The luminosity monitor is being commissioned. Very small rates were
observed (approx. 1Hz) last week. Yesterday, the rate was about 100Hz as
expected, although nothing was changed on the lumi monitor.
- Requested to close the calorimeter, to be scheduled.
HERMES
- The beam loss monitor is being tested. Background rates are very high and
have to be optimized.
- The effect of the transverse target magnet on the positron beam will be
studied on Thursday.
- The survey showed some misalignment of the vacuum system, will be
discussed in a special meeting.
HERA B
- Would like to start commissioning wire movement, to be scheduled.
Schedule
- Establish collisions in north and south IPs.
- HERMES transverse target magnet: Thursday.
We will continue to have weekly meetings.
Uwe Schneekloth