Minutes
from REX meeting 2004-07-28
Present:
General issues
* After the minutes
have been published a reminder with link should be sent to the following email
lists:
ab-dep-is-team (AB-ISOLDE Team)
isolde-physics-group@listbox4.cern.ch
miniball@mpi-hd.mpg.de
*
The budget planning for next
year should start:
Priorities set by REX team
Input from Nicolas David, David Porret, Sophie Meunier, RF group
etc..
* Thomas will
produce a priority list for spare parts and necessary work, presented in
August. From this, a shopping list (spares and development) adding up to 50 kCHF should be extracted and provided to P. Butler until
the end of the summer.
* The question
was raised if some money from the
*
The board for the REX control technician is the 16/8-2004.
* The XP upgrade
is almost finished. The EBIS NT FEC runs once again XP. The VME-GFAS problem
still remains, but the system is operational with the quickfix
by
*
The memory problem with the beam diagnostics FEC was solved by
* An updated
version of the REX homepage is coming together. A
final version should be released in the end of August.
Motivation (Fredrik)
Linac part
(Thomas)
*
The new ISOLDE operator begins
the 1s of Oct. His name is Magnus Eriksson.
*
The level of support from the vacuum group was discussed. This question and the
responsibility will be raised with the vacuum group leader.
* A meeting about
the 17F run has been held. Different approaches were discussed, and it was
concluded that the AlF solution is not viable due to
the strong contamination of CO2 from the plasma ion source. A possible molecule
could be LaF, however, the efficiency inside the EBIS remains unclear.
Contaminations in the ISOLDE mass spectrum should be checked. Alternatively,
17F without carrier could be considered, as the REX beam will anyway be
contaminated by 17O from the residual gas inside the EBIS. The ~100 pA contamination of 17O from the ISOLDE target can be handled
with less efficiency in the REXTRAP. To separate 17F from 17O a stripping foil
in front of the last bending magnet in the REX Linac
has to be employed, and the 17F9+ be selected. The practicalities (energy loss,
type, mounting) of the stripping foil has to be solved. Luis should contact the
spokesperson for the experiment.
REXTRAP
*
* Romain looks into the new Labview
based control system for the REXTRAP. He and Pierre will go to GSI in September.
He should also interact with Chabouh Yazidjian who knows the ISOLTRAP control system. The control system should be changed
during next shutdown. The effort is big and careful debugging needed. Romain Savreux should be around
until the migration is complete. Romain’s salary
should be allocated for in the next year’s budget.
*
Lisa produces an A/q- spectrum with restgas
contaminations that should be published on the REX homepage
and can be used as a guideline for which A/q-values that are uncontaminated.
Thereafter she should measure the x-ray background from the Linac.
*
Anne should simulate different mass resolving techniques inside the trap using
SIMION.
*
The ‘new’ VME is still working without interruption. The ion source sparking
has temporarily been cured.
*
Tests of charge exchange will be continued when noble gas beam is available
from ISOLDE.
*
The scintillator tube to be mounted in the REX mass
separator was broken at installation. A replacement tube is searched for by
Luis. If this can not be found,
REXEBIS
* The
implementation of the slow extraction from the EBIS has yet not been carried
out.
* The 60 kV HT
supply for the EBIS has been repaired by FuG Electronics
Germany. The supply should be picked up by
* Lars, the
summer student of Fredrik, is continuing the calculation of the theoretical
mass spectrum. It should result in a programme that can be used by the users to
predict absolute residual gas contaminations for different EBIS conditions
(breeding time, pressure etc).
* The EBIS needs LqHe filling on this Sun evening or Mon morning.
* A request of
oil change/repair of the mobile roughing pump for REX has been sent to the
vacuum group. The responsibility and level of support is unclear, so the task is
pending.
* Fredrik will be
absent 30/7 to 2/8 for a visit to the Manne Siegbahn Laboratory in
LINAC and Miniball
* Berdermann will arrive on Friday 30/7 and repair the 200
MHz amplifier over the weekend.
*
Thomas has some ideas how to produce 3 MeV/u without
with the currently available RF power of the 200 MHz amplifier. The 7-gap
resonators will still operate at a bunching phase but at a raised power level.
Calculations to check this before a possible test next week are on the way.
*
The
*
The two broken roughing pumps for the MINIBALL can not be cared for by the
vacuum group. An external company should do the job.
Contact Service 40-30, tel
164210, bat 927-R-T26
*
Thomas mentioned that he still needs some input from the
experimental/physicists side to specify the REX upgrade plans towards our russian colleagues. Decisions
about energy variability etc. shall be made now in September.
*
Thomas is absent one week for the LINAC conference, leaving 16/8. Matteo Pasini replaces him.
Minutes
taken by Fredrik Wenander