Minutes of HERA Meeting
15.01.2002
HERA
F.Willeke presented a new preliminary HERA schedule. The restart of HERA and the schedule for
luminosity operation has been delayed because of several reasons:
- The interlock tests took somewhat longer than scheduled. Some tests had
to be repeated.
- Two activated sections of the proton machine were found during the shutdown: SR 130 and WR 330. Both parts are in cold sections. X-raying
at SR 130 showed that the proton beam pipe is not in the proper position
due to a defective support (balls came out of a ball bearing). So far,
no defect was found X-raying at WR 330. Warm-up of both sections started
on Friday. Repair of the beam pipe support at SR130 has started this morning. A visual inspection is necessary to find the problem at WR. It is not
yet clear whether a super conducting magnet has to be removed.
According to the present, preliminary schedule proton beam will not be
available until 5.02.2002.
- Luminosity operation with reasonable positron current will not be possible
until additional collimators are installed. Design and preparation for
fabrication of a fixed collimator 62m upstream (NL62 and SL62) and two
movable vertical collimators 6m (NL6 and SL6) from the IP is in progress.
The present time estimate for installation of these new collimators
is 3.03. to 10.03.2002.
A new positron beam optics with reduced divergence was prepared, which
should reduce the synchrotron radiation produced close to the IP. It will
be tested once the positron machine is operational again.
HERMES
- The beam pipe was surveyed and adjusted (up to 3mm) to the correct position.
HERA B
- A small leak was found in the beam pipe. (A small scratch in the thin Al
beam pipe, which probably happened during installation in July.) The leak
was repaired using glue.
Polarimeter
- Laser maintenance was done. The polarimeter crew would like to test the
laser. This cannot be done when repair work is in progress in the west
section.
Uwe Schneekloth