A quest for new physics inside the neutron

Abstract

The lecture presents an overview of the quest for the new physics in low energy neutron phenomena. In addition to the traditional topics the quantum damping of nn oscillations is discussed.

The effect of collisions with the wall on neutron-antineutron transitions

“…In different models the imaginary part of the optical potential differs by almost an order of magnitude [20]. An attempt has been undertaken recently [21] to develop a model forn 12 6 C interaction. Carbon is a material which served as a target in the ILL experiment [5] and will be used in the ESS project [7].…”

“…The idea that it might be possible to minimize the randomization through a suitable choice of the wall material, trap size, or reflection angle was put forward long ago [8,9]. Since then the problem was at the focus of several publications [10][11][12] but despite some progress it is still pending. In the present work we try to analyse collisions with the wall from different angles.…”

Lindblad and Bloch equations for conversion of a neutron into an antineutron

“…The process of n −n oscillations for UCN (ultracold neutrons) trapped in a storage vessel has been studied in a number of papers, e.g., [29][30][31][32][33][34][35][36]. Here we want to look at this process from a new angle.…”

“…Note that in [12] the Hamiltonian contains 2π k nvf i (0)(i = 1, 2) without Lindblad terms in the evolution equation. The representation (35) allows to write the equation in the Lindblad form. Both parametrizations lead to the same physical results.…”

“…Both parametrizations lead to the same physical results. The terms 2π k nvRef i (0), (i = 1, 2) in (35) correspond to the energy shift related to forward scattering, i.e., the real part of the index of refraction. The Lindblad operator is defined as…”