title: Orientational Coherent Effects of High-Energy Particles in a LiNbO3 Crystal.
abstract: A bent lithium niobate strip was exposed to a 400-GeV/c proton beam at the external lines of CERN Super Proton Synchrotron to probe its capabilities versus coherent interactions of the particles with the crystal such as channeling and volume reflection. Lithium niobate (LiNbO3) exhibits an interplanar electric field comparable to that of Silicon (Si) and remarkable piezoelectric properties, which could be exploited for the realization of piezo-actuated devices for the control of high-energy particle beams. In contrast to Si and germanium (Ge), LiNbO3 shows an intriguing effect; in spite of a low channeling efficiency (3%), the volume reflection maintains a high deflection efficiency (83%). Such discrepancy was ascribed to the high concentration (10(4) per cm2) of dislocations in our sample, which was obtained from a commercial wafer. Indeed, it has been theoretically shown that a channeling efficiency comparable with that of Si or Ge would be attained with a crystal at low defect concentration (less than ten per cm2). To better understand the role of dislocations on volume reflection, we have worked out computer simulation via dynecharm++ Monte Carlo code to study the effect of dislocations on volume reflection. The results of the simulations agree with experimental records, demonstrating that volume reflection is more robust than channeling in the presence of dislocations.
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Bagli
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Guidi
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Mazzolari
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Bandiera
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Germogli
authors.affiliation: INFN Sezione di Ferrara, Dipartimento di Fisica e Scienze della Terra, Università di Ferrara Via Saragat 1, 44100 Ferrara, Italy.
authors.forename: A I
authors.initials: AI
authors.lastname: Sytov
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, Via Marzolo 8, 35131 Padova, Italy and INFN Laboratori Nazionali di Legnaro, Viale dell'Università 2, 35020 Legnaro, Italy.
authors.forename: D
authors.initials: D
authors.lastname: De Salvador
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, Via Marzolo 8, 35131 Padova, Italy and INFN Laboratori Nazionali di Legnaro, Viale dell'Università 2, 35020 Legnaro, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Argiolas
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, Via Marzolo 8, 35131 Padova, Italy and INFN Laboratori Nazionali di Legnaro, Viale dell'Università 2, 35020 Legnaro, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Bazzan
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Padova, Via Marzolo 8, 35131 Padova, Italy and INFN Laboratori Nazionali di Legnaro, Viale dell'Università 2, 35020 Legnaro, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Carnera
authors.affiliation: Università dell'Insubria, via Valleggio 11, 22100 Como, Italy and INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Berra
authors.affiliation: Università dell'Insubria, via Valleggio 11, 22100 Como, Italy and INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Bolognini
authors.affiliation: Università dell'Insubria, via Valleggio 11, 22100 Como, Italy and INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Lietti
authors.affiliation: Università dell'Insubria, via Valleggio 11, 22100 Como, Italy and INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Prest
authors.affiliation: INFN Sezione di Trieste, Via Valerio 2, 34127 Trieste, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Vallazza