Beam extraction studies at 900 GeV using a channeling crystal

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.Comment: 55 page

Channeling through Bent Crystals

“…This may improve the collimation of the beam which is important for preventing damage to equipment and improving the noise to signal ratio of experiments using the beam. Previous channeling experiments have examined this effect at circular accelerators including the RD22 experiment at the H8 beamline at the European Organization for Nuclear Research (CERN) [2] and the Tevatron at Fermilab [3].…”

<title>On the halo cleaning at the LHC by crystals</title>

“…The possibility of multi-turn proton capture into the planar channeling regime in bent crystals was extensively studied. [1][2][3] Active investigation of volume reflection 4 from bent crystal planes has been recently started. [5][6][7] A correlated particle scattering by atoms forming crystal planes constitute an essence of both methods.…”

Steering of an ultrarelativistic proton beam by a bent germanium crystal

“…If the plane curvature radius is below a critical value ͑Tsyganov radius͒, 1 a fraction of the particles is deflected all along the crystal length. The phenomenon is investigated for various applications in circular accelerators for beam steering, 2 extraction, and collimation, [3][4][5] as well as for splitting and focusing 6 of external beams. Moreover, the curved trajectories of the relativistic particles cause radiation emission and there are proposals to manufacture crystalline undulators with bent crystals.…”