BNL, Upton, Long Island, New York
High energy polarized proton beams are desired for exploring the proton spin structure as well as other spin dependent measurements. However, depolarizing mechanisms due to the interaction between the spin motion and the magnetic fields challenges accelerating polarized protons to high energy in circular accelerators. Several decades of efforts in developing techniques to preserve polarization to high energy have finally led to the success of the polarized proton program at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Designed to provide polarized proton collisions up to 250GeV, RHIC is equipped with two Siberian snakes to avoid both intrinsic and imperfection depolarizing resonances. Currently, polarization has been preserved up to 100 GeV at RHIC with precise control of orbit and betatron tunes. The polarized protons were first brought into collisions at 250GeV in RHIC in 2009, and depolarizations were observed between 100 GeV to 250 GeV. This presentation reports the progress of RHIC polarized proton program. Strategies of how to preserve the polarization through the RHIC injectors are also presented.
TUB, Beijing
Since being introduced to accelerator physics, I have had the privilege to study and work with some of the best physicists on some of the most exciting projects. My first assignment was to simulate transition-crossing in RHIC in which a shocking 86% beam loss led to a redesign of its RF system which later earned me a Ph.D. Participation in the design, R&D, construction, and the commissioning of RHIC, not only was I introduced to the fascinating world of accelerator physics but was also trained as a physicist for accelerator projects. Since then, I have had the opportunity to work and lead teams of physicists and engineers on accelerator projects: US-LHC/AP at BNL, SNS/AP at ORNL, SNS ring, CSNS in China, and now CPHS at Tsinghua. The accelerator profession is uniquely rewarding in that ideas and dreams can be turned into reality through engineering projects, through which one experiences endless learning in physics, technology, teamwork and friendship. An example of enjoying the fun and friendship is the work on crystalline beams as a hobby for the past 18 years.
*Wei, Li, Sessler, Okamoto PRL73(94)3089; 80(98)2606
*Wei, Harrison XVI RCNP Osaka(97)
*Wei et al PAC99 2921
*Wei et al PAC01(01)319
*Wei RMP75(03)1383
*Wei et al NIMA600(09)10
*Wei et al PAC09
CERN, Geneva
I will briefly describe CERN's colliders starting with the ISR, going through LEP, and finishing with the LHC. The common threads will be discussed in terms of people and techniques. I will start by describing the incredible impact on accelerator physics of the almost forgotten, first ever hadron collider, the ISR. I will then present the construction and 12 years of operation of LEP. Finally I will also provide the first results of beam operation in the LHC as well as the plans for the near and far future.
CERN, Geneva
GSI, Darmstadt
The Chair and Deputy will receive the award of the IPAC'10 Organizing Committee on behalf of the JACoW Collaboration.