Seminars Archive
Roberto Kersevan
Abstract
Tuesday, October 31, 2000, 15:30
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
Experience with Non-Evaporable Getter-Coated Insertion-Device Vacuum Chambers
at the ESRF
Roberto Kersevan
(European Synchrotron Radiation Facility, Grenoble, France)
ABSTRACT
In order to cope with new radiation limits for non-exposed workers
as dictated by EU legislation, and in order to extend the availability
of the experimental hutches following the installation of a new narrow-gap
vacuum chamber, a program of R&D aiming at improving the conditioning
and pressure profile of such chambers has been carried out at the ESRF.
The talk will summarize the results obtained so far on a number of NEG-coated
and un-coated vacuum chambers installed both in the storage ring and on
an beamline dedicated to photodesorption studies. It will be shown that
the deposition of a NEG-coating film developed at CERN has resulted in
desorption yields orders of magnitudes lower than that of the corresponding
un-coated materials. It will be also shown that the bremsstrahlung (BS)
radiation measured in one experimental hutch could be successfully lowered
by using such NEG-coated chambers. The rationale for preferring BS data
over the standard practice of using pressure gauge data for the determination
of the behaviour of such chambers will be outlined and discussed.
