AVS 52nd International Symposium
    Vacuum Technology Wednesday Sessions
       Session VT-WeA

Paper VT-WeA4
Beam Induced Dynamic Pressure Rise in RHIC

Wednesday, November 2, 2005, 3:00 pm, Room 201

Session: Hydrogen, Outgassing, and Vacuum Systems
Presenter: H. Hseuh, Brookhaven National Laboratory
Authors: H. Hseuh, Brookhaven National Laboratory
S.Y. Zhang, Brookhaven National Laboratory
Correspondent: Click to Email
Relativistic Heavy Ion Collider (RHIC) consists of two storage rings of 3.8 km in circumference for high energy and nuclear physics research. With increasing ion beam intensity during recent RHIC operations, rapid pressure rises of several decades were observed at most warm sections and at a few cold (4.5K) sections. The pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam ion induced desorption; and have been one of the major luminosity limiting factors. This dynamic pressure rises will be explained based on the observations at RHIC and the existing understandings. Some remedies to reduce the pressure rises, such as in-situ baking, NEG coating and solenoids, have been implemented over the last few years and their effectiveness will be illustrated. *Work performed under Contract No. DE-AC02-98CH1-886 with the auspices of the US Department of Energy.