Minutes from REX meeting 2004-12-08

Present: Pierre Delahaye, Mats Lindroos (chair), Luis Fraile, Thomas Sieber, Peter Butler, Romain Savreux, Fredrik Wenander, Dietrich Beck

General issues

* Mats has submitted a new proposal for how to solve the manpower situation at REX to S. Myers and the group leaders involved. A meeting to discuss the issue will be held next week.

* P. Butler explained that ISOLDE is about to bid to CERN for an intensity and energy (5 MeV/u) upgrade of ISOLDE and REX, the HIE-ISOLDE project. Mats, Luis and Peter will make a line of action. Input for estimating capital and manpower costs will be needed from the REX people.

* Next meeting, the final one for this year, will be held on Thursday, 16:00, in cafeteria nr 1. Peter will buy cakes for everyone?

REXTRAP and REXEBIS

* The imposed requirement for a gas recovery for the roughing pumps at the trap and EBIS before the startup 2005 was discussed. The idea to mix the high gas load from the trap with the separator exhausts is not ideal. The implementation of a recovery system with such a short notice after the shut down planning has been carried out is difficult. Mats will speak to Mr Strubin in the vacuum group, and as well with the DSO.

* The VME at the trap has been disconnected and replaced by a PC running the Labview based control system. The merge to the new system has proceeded very well. With only minor obstacles, most of them already resolved. The GPIB is now implemented, that is the cycles and the timing module are operational. The Profibus devices are under testing. If everything goes well a test with ions inside the trap could be performed in the end of the week and a TOF be produced.

* The cryostat of the REXEBIS solenoid was repaired last week. Some possible faults were corrected for. The cryostat has been remounted, leak tested and pumped on for 5 days. It is now cooled down to LHe temperature again and the hold time will be checked. A verification of the field alignment is also fore during the next week.

* The tearing down of the end wall in the experimental wall affects the alignment possibilities of the EBIS as one fixed point disappears. E. Siesling is looking into alternative solutions. Thomas promises that the existing points on the floor after the LINAC can be used for defining a new point.

LINAC

* The RF group has started to work on the phase shifters. Direct measurements of the tank phases are not feasible for the moments due to problems with four amplifiers.

Instead they measure the reference signal from the master oscillator in a test stand.

* The broken RFQ preamplifier has been sent to the Dressel company for repair.

* Berdermann at Bertronix has started to produce a new anode capacitor for the 200 MHz amplifier. He is expected to come to CERN sometime in January.

* Thomas in investigating the options for implementing a new RF application in the existing control system, allowing for remote control of the amplifiers. This could be useful also for Linac 2 and 3. Whom should do the application programming is unclear. Thomas will speak to Nikolai Trofimov to make sure that this action doesn’t disagree with his plans, and also ask Ivan Deloose for programming assistance.

Minutes taken by Fredrik Wenander

(The uncensored version can be given by Fredrik on request.)