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Thieberger, P.

Paper Title Page
TPAT094 Luminescence Beam Profile Monitor for the RHIC Polarized Hydrogen Jet Polarimeter 4293
 
  • N.P. Luciano, Y. Makdisi, A.N. Nass, P. Thieberger, D. Trbojevic, A. Zelenski
    BNL, Upton, Long Island, New York
 
  Funding: Work performed under Contract Number DE-AC02-98CH10886 with the auspicies of the US Deparment of Energy.

This is the second polarized proton run in Relativistic Heavy Ion Collider (RHIC) with a new polarized proton jet target used to provide accurate polarization measurements. The interactions between the stored polarized protons with the polarized jet target will produce, in addition to polarization, optical signals due to exited states of Hydrogen or other molecules, ions, or atoms. Additional lenses, optical window, optical analyzer, and the CCD camera are added to the system to allow transfer and detection of optical signals from the interaction chamber. Oxygen or other elements (impurities) could be mixed within the jet target and affect the accuracy of the polarization measurements. It is important to have continuous information of the jet content without affecting the polarization measurements. The optical signals coming from the exited states of molecules, ions, and atoms from the polarized proton beam interaction with the jet will provide that. In addition, the beam profile might be obtained.

 
TPAT095 Beam Induced Pressure Rise at RHIC 4308
 
  • S.Y. Zhang, J.G. Alessi, M. Bai, M. Blaskiewicz, P. Cameron, K.A. Drees, W. Fischer, J. Gullotta, P. He, H.-C. Hseuh, H. Huang, U. Iriso, R.C. Lee, V. Litvinenko, W.W. MacKay, T. Nicoletti, B. Oerter, S. Peggs, F.C. Pilat, V. Ptitsyn, T. Roser, T. Satogata, L. Smart, L. Snydstrup, P. Thieberger, D. Trbojevic, L. Wang, J. Wei, K. Zeno
    BNL, Upton, Long Island, New York
 
  Beam induced pressure rise in RHIC warm sections is currently one of the machine intensity and luminosity limits. This pressure rise is mainly due to electron cloud effects. The RHIC warm section electron cloud is associated with longer bunch spacings compared with other machines, and is distributed non-uniformly around the ring. In addition to the countermeasures for normal electron cloud, such as the NEG coated pipe, solenoids, beam scrubbing, bunch gaps, and larger bunch spacing, other studies and beam tests toward the understanding and counteracting RHIC warm electron cloud are of interest. These include the ion desorption studies and the test of anti-grazing ridges. For high bunch intensities and the shortest bunch spacings, pressure rises at certain locations in the cryogenic region have been observed during the past two runs. Beam studies are planned for the current 2005 run and the results will be reported.

Work performed under the auspices of the US Department of Energy.

 
RPAT027 Tomographic Measurement of Longitudinal Emittance Growth Due to Stripping Foils 2000
 
  • C. Montag, L. Ahrens, P. Thieberger
    BNL, Upton, Long Island, New York
 
  Funding: Work performed under the auspices of the US Department of Energy.

During beam acceleration at the Brookhaven accelerator complex, heavy ions are stripped off their electrons in several steps. Depending on the properties of the stripping foils, this process results in an increased energy spread and therefore longitudinal emittance growth. A tomographic phase space reconstruction technique has been applied to quantify the associated emittance growth for different stripping foil materials.

 
ROAD003 Post-Irradiation Properties of Candidate Materials for High-Power Targets 333
 
  • H.G. Kirk, H. Ludewig, L.F. Mausner, N. Simos, P. Thieberger
    BNL, Upton, Long Island, New York
  • Y. Hayato, K. Yoshimura
    KEK, Ibaraki
  • K.T. McDonald
    PU, Princeton, New Jersey
  • J. Sheppard
    SLAC, Menlo Park, California
  • L.P. Trung
    Stony Brook University, Stony Brook
 
  Funding: U.S. DOE.

The long term survivability of materials which can be used either for high-intensity targets or for the environment surrounding the target can be greatly influenced by how the physical properties of the material are altered by radiation damage. We have irradiated several candidate materials and report here on physical properties before and after irradiation.