NN correlations measured in <Superscript>3</Superscript>He(e,e'pp)n

We have measured the ³He (e, e'pp)n reaction in the Jefferson Lab CLAS with 2.2 and 4.4 GeV electrons. We looked at the energy distribution of events with all three nucleons at high momentum (p > 250 MeV/c). This distribution has peaks where two nucleons each have 20% or less of the energy transfer (i.e., the third or ?leading? nucleon carries most of the kinetic energy). The angular distribution of these two ?fast? nucleons shows a very large back-to-back peak, indicating the effect of correlations. While there is some theoretical disagreement, experimental evidence, plus calculations at lower energy by W. Glöckle, indicates that these events are primarily sensitive to NN correlations.Received: 1 November 2002, Published online: 15 July 2003PACS: 21.45.+v Few-body systems - 25.30.Dh Inelastic electron scattering to specific statesL.B. Weinstein: For the CLAS Collaboration     

Aharonov–Bohm Interferometry Based on Helical Edge States (Brief Review)

JETP Letters - We review recent studies of the spin-dependent tunneling transport via an Aharonov–Bohm interferometer (ABI) formed by helical edge states. We focus on the experimentally...     

Two-nucleon momentum distributions measured in 3He(e,e'pp)n

We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic range. The kinetic energy distribution for "fast" nucleons (p>250 MeV/c) peaks where two nucleons each have 20% or less, and the third nucleon has most of the transferred energy. These fast pp and pn pairs are back to back with little momentum along the three-momentum transfer, indicating that they are spectators. Calculations by Sargsian and by Laget also indicate that we have measured distorted two-nucleon momentum distributions by striking one nucleon and detecting the spectator correlated pair.     

Magnetic orientational phase transition in a biaxially strained single crystal Ho0.6Y2.4Fe5O12

The evolution of the domain structure of a Ho_0.6Y_2.4Fe₅O₁₂ single crystal under the action of biaxial mechanical stresses was investigated using the magneto-optical method. The investigations were performed on a specimen in the form of a plane-parallel plate that was cut parallel to the (110) crystallographic plane. The mechanical stresses in the specimen were induced by the compressive forces acting on it and oriented in the (110) plane along the directions ??100?? and ??110??. It was found that, under stresses induced in the specimen, the reorientation of the easy magnetization axis occurs through a first-order phase transition. The obtained results were discussed in terms of the thermodynamic theory of magnetic orientational phase transitions.