Speaker
Dr
Andrea Mazzolari
(Ferrara)
Description
Channeling effect in bent crystals is used as a power tool for beam steering. Motion of a channeled particle is characterized by oscillations between neighbor bent atomic planes. We studied the interaction between a 2 MeV proton beam and an unbent crystal as thin as 92 nm, i.e. half of the oscillation wavelength, demonstrating that also an unbent crystal can be used to steer charged particle beams. As the nominal beam direction is inclined by less than the critical angle for planar channeling with respect to the crystal planes, under-barrier particles undergo half an oscillation and exit the crystal with the reversal of the transverse momenta; i.e., the protons are ‘‘mirrored’’ by the crystal planes. Over-barrier particles suffer deflection, too, to a direction opposite that of mirroring. On the strength of such coherent interactions, charged particle beams can be efficiently steered through an ultrathin unbent crystal by the same physical processes as for thicker bent crystals.
Primary authors
Dr
Andrea Mazzolari
(Ferrara)
Dr
Davide De Salvador
(Dipartimento di Fisica, Universita` di Padova, Via Marzolo n.8, 35131 Padova, Italy)
Mr
Luca Bacci
(Dipartimento di Fisica, Universita` di Padova, Via Marzolo n.8, 35131 Padova, Italy)
Prof.
Vincenzo Guidi
(INFN Sezione di Ferrara and Dipartimento di Fisica, Universita` di Ferrara, Via Saragat 1/C, 44122 Ferrara, Italy)
