134 research outputs found
Spin light in neutrino transition between different mass states
The spin light of neutrino is considered in the process of a neutrino
radiative transition between two different mass states in presence of medium.
By this study we investigate the influence of background matter on the initial
and final neutrino states in the process of massive Dirac neutrino decay due to
the non-zero transition magnetic moment. We derive corresponding corrections to
the total width of the process over the matter density in most important for
applications cases.Comment: 5 pages in LaTex, to appear in proceedings of the 9th Conference on
Quantum Field Theory Under the Influence of External Conditions (Univ. of
Oklahoma, Norman, OK USA, September 21-25, 2009), eds. Kim Milton and Michael
Bordag (World Scientific, Singapore, 2010
Spin light of electron in matter
We further generalize the powerful method, which we have recently developed
for description of the background matter influence on neutrinos, for the case
of an electron moving in matter. On the basis of the modified Dirac equation
for the electron, accounting for the standard model interaction with particles
of the background, we predict and investigate in some detail a new mechanism of
the electromagnetic radiation that is emitted by moving in matter electron due
to its magnetic moment. We have termed this radiation the ``spin light of
electron" in matter and predicted that this radiation can have consequences
accessible for experimental observations in astrophysical and cosmological
settings.Comment: 5 pages in LaTex, in: "Particle Physics at the Year of 250th
Anniversary of Moscow University", ed. by A.Studenikin, World Scientific,
Singapore, 2006, p. 73 (Proceedings of the 12th Lomonosov Conference on
Elementary Particle Physics, August 2005, Moscow
X-ray study of the liquid potassium surface: structure and capillary wave excitations
We present x-ray reflectivity and diffuse scattering measurements from the
liquid surface of pure potassium. They strongly suggest the existence of atomic
layering at the free surface of a pure liquid metal with low surface tension.
Prior to this study, layering was observed only for metals like Ga, In and Hg,
the surface tensions of which are 5-7 fold higher than that of potassium, and
hence closer to inducing an ideal "hard wall" boundary condition. The
experimental result requires quantitative analysis of the contribution to the
surface scattering from thermally excited capillary waves. Our measurements
confirm the predicted form for the differential cross section for diffuse
scattering, where , over a range of and that is larger than
any previous measurement. The partial measure of the surface structure factor
that we obtained agrees with computer simulations and theoretical predictions.Comment: 7 pages, 7 figures; published in Phys. Rev.
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