• O.B. Malyshev
  ASTeC, Daresbury
• M.C. Bellachioma, H. Kollmus, A. Krämer, H. Reich-Sprenger
  GSI, Darmstadt
• M. Bender
  LMU, München
• M. Leandersson
  KTH Physics, Stockholm
• E. Hedlund, L. Westerberg
  Uppsala University/Dept. Phys. and Astr., Uppsala
• A. Krasnov
  BINP, Novosibirsk
• B. Zajec
  JSI, Ljubljana

Funding: This work was performed with support from the EUFP6 Program DIRAC-PHASE-1.

In­ten­si­ty of heavy ion ac­cel­er­a­tors can be lim­it­ed by beam in­duced pres­sure in­sta­bil­i­ty; if pump­ing is in­suf­fi­cient, pres­sure will steadi­ly grow re­duc­ing the beam life­time. There is a need of input pa­ram­e­ters for vac­u­um mod­elling and de­sign of safe UHV sys­tems for up­dat­ed and new heavy ion ac­cel­er­a­tors, such as the FAIR fa­cil­i­ty at GSI, as well as an in­ten­tion to gain a deep­er un­der­stand­ing of the des­orp­tion pro­cess re­quired an ex­per­i­men­tal in­ves­ti­ga­tion of the ion in­duced des­orp­tion yields (num­ber of re­leased molecules per in­ci­dent ion) from dif­fer­ent ma­te­ri­als com­mon­ly used in par­ti­cle ac­cel­er­a­tors. The ex­per­i­men­tal data have been ob­tained with per­pen­dic­u­lar in­ci­dence beams with an ex­per­i­men­tal setup based on the through­put method lo­cat­ed at the Sved­berg lab­o­ra­to­ry in Up­p­sala (Swe­den). The in­ves­ti­gat­ed ma­te­ri­als were ¹¹⁶In, Cu, etched Cu, gold coat­ed Cu and Ta and the cho­sen beams were 5 MeV/u Ar⁸⁺, 9.6 MeV/u Ar⁹⁺ and 17.7 MeV/u Ar¹²⁺. The sam­ples can be bi­ased, which means that the amount of sec­ondary out­go­ing pos­i­tive and neg­a­tive par­ti­cles dur­ing ion bom­bard­ment could be in­ves­ti­gat­ed. A few sam­ples were also bom­bard­ed with graz­ing in­ci­dent angle. A sum­ma­ry of the re­sults will be re­port­ed.