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Beam extraction studies at 900 GeV using a channeling crystal

R. A. Carrigan Jr.·D. Chen·G. Jackson·N. Mokhov·C. T. Murphy·S. Baker·A. Bogacz·D. Cline·S. Ramachandran·J. Rhoades·J. Rosenzweig·A. Asseev·V. Biryukov·A. Taratin·J. A. Ellison·A. Khanzadeev·T. Prokofieva·V. Samsonov·G. Solodov·B. Newberger·E. Tsyganov·H. J. Shih·W. Gabella·B. Cox·V. Golovatyuk·A. McManus
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Abstract

Luminosity-driven channeling extraction has been observed for the first time in a 900 GeV study at the Fermilab Tevatron. This experiment, Fermilab E853, demonstrated that useful TeV level beams can be extracted from a superconducting accelerator during high luminosity collider operations without unduly affecting the background at the collider detectors. Multi-turn extraction was found to increase significantly the efficiency of the process. The beam extraction efficiency was about 25%. Studies of time dependent effects found that the turn-to-turn structure was governed mainly by accelerator beam dynamics. An investigation of a pre-scatterer using the accelerator flying wire system showed that a fiber could produce a significant extracted flux, consistent with expectations. Based on these results, it is feasible to construct a parasitic 5-10 MHz proton beam from the Tevatron collider.

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R. A. Carrigan Jr., D. Chen, G. Jackson, N. Mokhov, C. T. Murphy, S. Baker, A. Bogacz, D. Cline, S. Ramachandran, J. Rhoades, J. Rosenzweig, A. Asseev, V. Biryukov, A. Taratin, J. A. Ellison, A. Khanzadeev, T. Prokofieva, V. Samsonov, G. Solodov, B. Newberger, E. Tsyganov, H. J. Shih, W. Gabella, B. Cox, V. Golovatyuk, A. McManus. 1999-09-29. Beam extraction studies at 900 GeV using a channeling crystal. https://doi.org/10.1103/physrevstab.5.043501

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