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Recent interest in spectroscopic factors for single-neutron transfer in low-spin states of the even-odd Xenon $^{125,127,129.131}$Xe and even-odd Tellurium, $^{123,125,127,129,131}$Te isotopes stimulated us to study these isotopes within the frame wo rk of the Interacting Boson-Fermion Model. The fermion that is coupled to the system of bosons is taken to be in the positive parity $3s_{1/2}$, $2d_{3/2}$, $2d_{5/2}$, $1g_{7/2}$ and in the negative $1h_{11/2}$ single-particle orbits, the complete 50-82 major shell. The calculated energies of low-spin energy levels of the odd isotopes are found to agree well with the experimental data. Also B(E2), B(M1) values and spectroscopic factors for single-neutron transfer are calculated and compared with experimental data.
A particle cascade (shower) in a dielectric, for example as initiated by an ultra-high energy cosmic ray, will have an excess of electrons which will emit coherent v{C}erenkov radiation, known as the Askaryan effect. In this work we study the case in which such a particle shower occurs in a medium just below its surface. We show, for the first time, that the radiation transmitted through the surface is independent of the depth of the shower below the surface when observed from far away, apart from trivial absorption effects. As a direct application we use the recent results of the NuMoon project, where a limit on the neutrino flux for energies above $10^{22}$,eV was set using the Westerbork Synthesis Radio Telescope by measuring pulsed radio emission from the Moon, to set a limit on the flux of ultra-high-energy cosmic rays.
The generic properties of the emission of coherent radiation from a moving charge distribution are discussed. The general structure of the charge and current distributions in an extensive air shower are derived. These are subsequently used to develop a very intuitive picture for the properties of the emitted radio pulse. Using this picture can be seen that the structure of the pulse is a direct reflection of the shower profile. At higher frequencies the emission is suppressed because the wavelength is shorter than the important length scale in the shower. It is shown that radio emission can be used to distinguish proton and iron induced air showers.
Particle cascades initiated by ultra-high energy (UHE) neutrinos in the lunar regolith will emit an electromagnetic pulse with a time duration of the order of nano seconds through a process known as the Askaryan effect. It has been shown that in an o bserving window around 150 MHz there is a maximum chance for detecting this radiation with radio telescopes commonly used in astronomy. In 50 hours of observation time with the Westerbork Synthesis Radio Telescope array we have set a new limit on the flux of neutrinos, summed over all flavors, with energies in excess of $4times10^{22}$ eV.
We show that at wavelengths comparable to the length of the shower produced by an Ultra-High Energy cosmic ray or neutrino, radio signals are an extremely efficient way to detect these particles. First results are presented of an analysis of 20 hours of observation data for NuMoon project using the Westerbork Synthesis Radio Telescope to search for short radio pulses from the Moon. A limit on the neutrino flux is set that is a factor four better than the current one (based on FORTE).
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