The schemes of proton extraction from IHEP accelerator using bent crystals

Abstract

Abstract. IHEP Protvino has pioneered the wide practical use of bent crystals as optical elements in high-energy beams for beam extraction and deflection on permanent basis since 1989. In the course of IHEP experiments, crystal channeling has been developed into efficient instrument for particle steering at accelerators, working in predictable, reliable manner with beams of very high intensity over years. Crystal systems extract 70 GeV protons from IHEP main ring with efficiency of 85% at intensity of 10 12 , basing on multi-pass mechanism of channeling proposed theoretically and realised experimentally at IHEP. Today, six locations on the IHEP 70-GeV main ring of the accelerator facility are equipped by crystal extraction systems, serving mostly for routine applications rather than for research and allowing a simultaneous run of several particle physics experiments, thus significantly enriching the IHEP physics program. The long successful history of large-scale crystal exploitation at IHEP should help to incorporate channeling crystals into accelerator systems worldwide in order to create unique systems for beam delivery. We report recent results from the research and exploitation of crystal extraction systems at IHEP.

Possibility of crystal extraction and collimation in the sub-GeV range

“…The technique was applied at up to world highest energy [4,8], in good agreement with predictions [11]. In IHEP Protvino, much of the physics program relies on crystal channeled beams used regularly since 1989 [10]. Crystal systems extract 70 GeV protons from the IHEP main ring with efficiency of 85% at proton beam intensities of 4 10 12 .…”

“…The experience in crystal extraction shows that this method may have additional benefits such as a flat time structure of the extracted beam [10].…”

“…The studies of beam extraction and collimation assisted by channeling in a bent crystal have progressed well in recent decades [1][2][3][4][5][6][7][8][9][10]. The technique was applied at up to world highest energy [4,8], in good agreement with predictions [11].…”

Experiments with crystal deflectors for high energy ion beams: Electromagnetic dissociation probability for well channeled ions

“…Afterwards, particle channeling in bent crystals had been studied in many experiments at the CERN, Institute for High Energy Physics (IHEP), and Fermi National Accelerator Laboratory (see the reviews [4][5][6]). Bent crystals are successfully used at the IHEP to extract the proton beam from the synchrotron U70 and for the beam splitting between the experiments [7]. At the present time, the possibility to use a crystal deflector as a primary collimator of the LHC beam halo collimation system is studied in the UA9 experiment at the Super Proton Synchrotron (SPS) beams [8][9][10].…”

Positron Facilities Tests of the X-Rays Produced by Crystalline Undulators

“…20 by an angle of about 1 mrad and installed in a circulating accelerated beam.This angle of bending is sufficient to separate in space the circulating and deflected (by a crystal) beams. The effect of the deflection of a part of a beam as a result of channeling was registered by a secondary emission detector, located in a vacuum chamber of an accelerator near experiment that the crystal cross-section is efficiently channeling high energy particles, similarly to usual crystal deflectors (see [18]). The experimentally established transparency for channeling of high energy particles allows one to start a direct experiment on photon production from an e + beam in the CU (see [19]).…”