MEETING FOR RFQ COOLER AND BUNCHER AT ISOLDE PROJECT

Minutes of the ISCOOL Meeting

ISOLDE, CERN, 2005-09-21

Presents: Cyril Bachelet ; Richard Catherall; Pierre Delahaye (chair) ; Gerrit Jan Focker; Luis Mario Fraile Prieto; Alexandre Dorsival; Tim Giles; Ari Jokinen; Magdalena Kowalska; Frank Locci; Mats Lindroos (co-chair); Ivan Podadera ; Karsten Riisager; Erwin Siesling

Excused: Julien Parra-Lopez ; Sophie Meunier

This combined technical coordination and EURISOL task 9 meeting was held at ISOLDE on the 21^st of September 2005 during an exceptional visit of Ari Jokinen. Its purpose was the organization of the work related to the RFQ cooler “ISCOOL” for its off-line tests in building 275 and its future installation in the ISOLDE Hall especially after the leave of Ivan. Some further considerations coming from prior and later discussions have been added for correctness and completeness.

Present status

The present status was given by Ivan who presented some slides. The quadrupole has been assembled and should be soon disassembled for ultrasound cleaning. The vacuum pumps have been received and all the items of the vacuum system are ready. For the on-line installation, the integration of the RFQ vacuum system in the control of ISOLDE has first to be discussed with the vacuum group, as it was reported in a recent discussion with Frank Locci. The support of the injection cross-piece should be delivered mid-October. The Labview control system has been developed by Tuomas Tallinen. The only missing part for now is the timing signals. It should be sufficient for a first use of ISCOOL at ISOLDE. The quadrupole triplets at the injection and extraction of the RFQ have to be designed. They constitute at the moment the most urgent item to deal with. The workshop of the University of Mainz may help with their machining thanks to Klaus Blaum.

Tests in 275:

For the installation the vacuum group – Sophie and David - shall punctually provide a bit of support if needed. Gerrit Jan will look for a MCP-phosphor screen assembly which could be available by the beam diagnostic group. In the first tests the LPC Caen surface ionization source could be used without the injection quadrupoles and using an acceleration voltage of a few thousands of volts. Eventually at the end of the beamtime 2006 the RFQ cooler could be placed in La0 or La1 beamlines, or in front of the COLLAPS setup for a commissioning with radioactive beams. In order to avoid this difficult step it was proposed by Ari to use a sputtering radioactive ion source in 275. Alexander has been asked for an investigation of this possibility by the radioprotection.

Installation in the ISOLDE hall:

The installation is foreseen in the end of the year 2006 after the beamtime period. Mats and Richard reported on a discussion with the vacuum group. The roughing pump close to the HRS switchyard will be moved in the separator zone. The exhaust of the RFQ pumps will need to be connected to a second recovery balloon, most likely the future one of REX-ISOLDE. As it was specified lately by Sophie, three conditions are necessary for the vacuum group to undertake this work: 1) the implantation schemes for exhaust lines and valves should be accurately defined 2) the related mechanical works should have been organized 3) the schedule should be kept because of operation constraints with HRS. During the ISOLDE technical coordination meeting of the 20/09 Julien reported on the difficulty of inserting the power supply racks in the high voltage cage of the RFQ in such a small area. He shall have a visit this week with Ivan in the hall. Alexander stressed the fact that the RFQ cooler could become an important source of radiations in the hall in the case of intense beams and if the losses during the cooling process are non negligible, i.e. for transport efficiency significantly lower than 100%.

Manpower situation:

Ivan will follow the developments of the RFQ until the end of October. After this date, Tim agreed to take in charge the coordination of the project for the commissioning in 275. There won’t certainly be any intensive tests before end of January 2006. Most of the work will be related to vacuum installation, injection quadrupole machining, vacuum PLC - control system communication, beam diagnostics installation. All these works will be undertaken under the supervision of Tim according to the availability of resources defined below. The section of Richard will provide some mechanical support for the final installation of the RFQ in 275. During the off-line tests a PhD student from the group of Jon Billowes could possibly be available if the application for a CERN doctoral position is successful. A postdoc could also provide an extended support especially in the weeks of intensive testing. Pierre and Ari have proposed a possible help – to be defined - from people from respectively LPC Caen and JYFL. Technical support might be also available from these institutes and from Manchester. At last a fellow might be hired by the section of Tim. This position would be advertised before March 26, 2006.

Minutes by Pierre and Ivan