The spin statistics connection for dyons

Goldhaber's spin-statistics connection for electric-pole-magnetic-pole composite dyons is deduced in a gauge-invariant way by connecting the spatial interchange operator with a rotation.Supported in part by the National Science Foundation.Supported in part by the National Science Foundation.     

Pions as spin waves: Chiral symmetry breaking in lattice gauge theory

In hamiltonian lattice gauge theory, the fermion vacuum at lowest order in 1/g² can be determined from degenerate perturbation theory plus mean field-spin wave techniques. Using compact QED as an example, we show that: (i) chiral symmetry is spontaneously broken; and (ii) $\text{m}{}_{\mathrm{<mtext>pseudoGoldstone</mtext>}}{}^2\text{∝ m}{}_{\mathrm{<mtext>fermion</mtext>}}\text{〈}\text{ψ}\text{ψ〉}$. The pseudoscalar pseudoGoldstone particles—the “pions” of this abelian theory—correspond to antiferromagnetic spin wave excitations of the fermion vacuum.     

Dark matter profile in the galactic center

We describe a quasiequilibrium profile of dark matter particles in the inner parsec of the Galaxy, rhodm proportional to r(-3/2). This "minicusp" profile is caused by scattering with the dense stellar cluster around the supermassive black hole in Sgr A* and is independent of the initial conditions. The implications for detection of gamma rays from annihilation of weakly interacting massive dark matter particle in the Galactic center are a mild enhancement of the flux and a characteristic central feature in the angular distribution which could be detectable by high-resolution atmospheric Cherenkov telescopes.     

Synchrotron radiation of crystallized beams

We study the modifications of synchrotron radiation of charges in a storage ring as they are cooled. The pair correlation lengths between the charges are manifest in the synchrotron radiation and coherence effects exist for wavelengths longer than the coherence lengths between the charges. Therefore, the synchrotron radiation can be used as a diagnostic tool to determine the state (gas, liquid, crystal) of the charged plasma in the storage ring. We show also that the total power of the synchrotron radiation is significantly reduced for crystallized beams, both coasting and bunched. This opens the possibility of accelerating particles to ultrarelativistic energies using small-sized cyclic accelerators.     

Suppression of synchrotron radiation due to beam crystallization

With respect to a “hot”, non-crystallized beam the synchrotron radiation of a cold crystallized beam is considerably modified. We predict suppression of synchrotron radiation emitted by a crystallized beam in a storage ring. We also propose experiments to detect this effect. Received: 19 June 1998 / Revised version: 10 August 1998     

Finite temperature radiative corrections to neutron decay and related processes

We present a detailed calculation of the radiative corrections at finite temperature to the processes nν ? pe, ne ? pν. and n ? peν. The temperature range considered is approximately 100 keV to 3 MeV, which is the range relevant for nucleosynthesis calculations. Photon absorption and emission, photonic corrections to the vertex and fermion wave-function renormalizations, as well as the correction to the electron “mass” are calculated explicitly. It is shown that infrared divergences are only cancelled when absorption and induced photon emission are included. We analyze the effect of these processes on the various reaction rates, and discuss the effects of these corrections on the calculated helium abundance in the universe.