Crystal undulator experiment at IHEP

Accelerator-based sources of hard-photon radiation are a rapidly developing field. Coherent radiation of a particle beam in an undulator is a popular choice. The crystalline undulators with periodically deformed crystallographic planes offer electromagnetic fields of the order of 1000 T and could provide a period L in the sub-millimeter range. In this way, a hundred-fold gain in the energy of emitted photons would be reached, as compared to a usual undulator. The first real construction of a crystal channeling undulator was recently proposed and realised by the present collaboration. After the sine-like deformation of crystal was proven in X-ray tests, four undulators were tested for channeling in a beam of 70-GeV protons. It was observed in the experiment that the crystal cross-section is efficiently channeling high energy particles, similarly to usual crystal deflectors. The experimentally established transparence for channeling of high energy particles allows one to start a direct experiment on photon production from a positron beam in the crystalline undulator. Details of commissioning of the experimental setup in the first run with 3 GeV positron beam are presented

Deflection of 400 GeV/c proton beam with bent silicon crystals at the CERN Super Proton Synchrotron

This paper presents a detailed study of the deflection phenomena of a 400 GeV/c proton beam impinging on a new generation of bent silicon crystals; the tests have been performed at the CERN Super Proton Synchrotron H8 beam line. Channeling and volume reflection angles are measured with an extremely precise goniometer and with high resolution silicon microstrip detectors. Volume reflection has been observed and measured for the first time at this energy, with a single-pass efficiency as large as 98%, in good agreement with the simulation results. This efficiency makes volume reflection a possible candidate for collimation with bent crystals at the CERN Large Hadron Collider

High-efficiency volume reflection of an ultrarelativistic proton beam with a bent silicon crystal

The volume reflection phenomenon was detected while investigating 400 GeV proton interactions with bent silicon crystals in the external beam H8 of the CERN Super Proton Synchrotron. Such a process was observed for a wide interval of crystal orientations relative to the beam axis, and its efficiency exceeds 95%, thereby surpassing any previously observed value. These observations suggest new perspectives for the manipulation of high-energy beams, e. g., for collimation and extraction in new-generation hadron colliders, such as the CERN Large Hadron Collider

Deflection of 400 GeV/c proton beam with bent silicon crystals at the CERN Super Proton Synchrotron

This paper presents a detailed study of the deflection phenomena of a 400 GeV/c proton beam impinging on a new generation of bent silicon crystals; the tests have been performed at the CERN Super Proton Synchrotron H8 beam line. Channeling and volume reflection angles are measured with an extremely precise goniometer and with high resolution silicon microstrip detectors. Volume reflection has been observed and measured for the first time at this energy, with a single-pass efficiency as large as 98%, in good agreement with the simulation results. This efficiency makes volume reflection a possible candidate for collimation with bent crystals at the CERN Large Hadron Collider

Double volume reflection of a proton beam by a sequence of two bent crystals

The doubling of the angle of beam deflection due to volume reflection of protons by a sequence of two bent silicon crystals was experimentally observed at the 400 GeV proton beam of the CERN SPS. A similar sequence of short bent crystals can be used as an efficient primary collimator for the Large Hadron Collider

High-efficiency volume reflection of an ultrarelativistic proton beam with a bent silicon crystal

The volume reflection phenomenon was detected while investigating 400 GeV proton interactions with bent silicon crystals in the external beam H8 of the CERN Super Proton Synchrotron. Such a process was observed for a wide interval of crystal orientations relative to the beam axis, and its efficiency exceeds 95%, thereby surpassing any previously observed value. These observations suggest new perspectives for the manipulation of high-energy beams, e. g., for collimation and extraction in new-generation hadron colliders, such as the CERN Large Hadron Collider

Apparatus to study crystal channeling and volume reflection phenomena at the SPS H8 beamline

none52A high performance apparatus has been designed and built by the H8-RD22 collaboration for the study of channeling and volume reflection phenomena in the interaction of 400 GeV/c protons with bent silicon crystals, during the 2006 data taking in the external beamline H8 of the CERN SPS. High-quality silicon short crystals were bent by either anticlastic or quasimosaic effects. Alignment with the highly parallel (8 µrad divergence) proton beam was guaranteed through a submicroradian goniometric system equipped with both rotational and translational stages. Particle tracking was possible by a series of silicon microstrip detectors with high-resolution and a parallel plate gas chamber, triggered by various scintillating detectors located along the beamline. Experimental observation of volume reflection with 400 GeV/c protons proved true with a deflection angle of (10.4±0.5) µrad with respect to the unperturbed beam, with a silicon crystal whose (111) planes were parallel to the beam.noneW. Scandale; I. Efthymiopoulos; D. A. Still; A. Carnera; G. Della Mea; D. De Salvador; R. Milan; A. Vomiero; S. Baricordi; S. Chiozzi; P. Dalpiaz; C. Damiani; M. Fiorini; V. Guidi;G. Martinelli; A. Mazzolari; E. Milan; G. Ambrosi; P. Azzarello; R. Battiston; B. Bertucci; W. J. Burger; M. Ionica; P. Zuccon; G. Cavoto; R. Santacesaria; P. Valente; E. Vallazza;A. G. Afonin; V. T. Baranov; Y. A. Chesnokov; V. I. Kotov; V. A. Maisheev; I. A. Yazynin; S. V. Afanasiev; A. D. Kovalenko; A. M. Taratin; N. F. Bondar; A S. Denisov; Y. A. Gavrikov; Y. M. Ivanov; V. G. Ivochkin; S. V. Kosyanenko; L. P. Lapina; P. M. Levtchenko; A. A. Petrunin; V. V. Skorobogatov; V. M. Suvorov; D. Bolognini; L. Foggetta; S. Hasan; M. PrestW., Scandale; I., Efthymiopoulos; D. A., Still; A., Carnera; G., Della Mea; D., De Salvador; R., Milan; A., Vomiero; Baricordi, Stefano; S., Chiozzi; Dalpiaz, Pietro; Damiani, Chiara; Fiorini, Massimiliano; Guidi, Vincenzo; Martinelli, Giuliano; Mazzolari, Andrea; Milan, Emiliano; G., Ambrosi; P., Azzarello; R., Battiston; B., Bertucci; W. J., Burger; M., Ionica; P., Zuccon; G., Cavoto; R., Santacesaria; P., Valente; E., Vallazza; A. G., Afonin; V. T., Baranov; Y. A., Chesnokov; V. I., Kotov; V. A., Maisheev; I. A., Yazynin; S. V., Afanasiev; A. D., Kovalenko; A. M., Taratin; N. F., Bondar; A. S., Denisov; Y. A., Gavrikov; Y. M., Ivanov; V. G., Ivochkin; S. V., Kosyanenko; L. P., Lapina; P. M., Levtchenko; A. A., Petrunin; V. V., Skorobogatov; V. M., Suvorov; D., Bolognini; L., Foggetta; S., Hasan; M., Pres