George M. Frichter

Limits on the Ultra-High Energy Electron Neutrino Flux from the RICE Experiment

Abstract Upper limits are presented on the diffuse flux of ultra-high energy νe, based on analysis of data taken by the RICE experiment during August, 2000. The RICE receiver array at South Pole monitors cold ice for radio-wavelength Cherenkov radiation resulting from neutrino induced in-ice showers. For energies above 1 EeV, RICE is an effective detector of over 15 km3 sr. Potential signal events are separated from backgrounds using vertex location, event reconstruction, and signal shape. These are the first terrestrial limits exploiting the physics of radio-Cherenkov emissions from charged current νe+N→e+N′ interactions.

Performance and simulation of the RICE detector

Abstract The Radio Ice Cherenkov Experiment at the South Pole, co-deployed with the AMANDA experiment, seeks to detect ultra-high energy electron neutrinos interacting in cold polar ice. Such interactions produce electromagnetic showers, which emit radio-frequency Cherenkov radiation. We describe the experimental apparatus and the procedures used to measure the neutrino flux.

Neutrino absorption tomography of the Earth's interior using isotropic ultra-high energy flux

Abstract We study the feasibility of using an isotropic flux of cosmic neutrinos in the energy range of 10 to 10000 TeV to study the interior structure of Earth. The angular distribution of events in a ∼ km 3 -scale neutrino telescope can be inverted to yield information on the Earths mass distribution that is independent of other methods. The energy spectrum of the neutrino primaries is also determined from consistency with the angular distribution. It is possible to make a model independent determination of the density profile of Earths interior, separate from the absolute normalization of the incident cosmic neutrinos.

Quark-based description of nuclear matter with simulated annealing

The ground‐state properties of a many‐quark system in the string‐flip model using variational Monte Carlo methods are calculated. The many‐body potential energy of the system is determined by finding the optimal grouping of quarks into hadrons. This (optimal) assignment problem is solved by using the stochastic optimization technique of simulated annealing. Results are presented for the energy and length‐scale for confinement as a function of density. These results show how quarks clustering decreases with density and characterize the nuclear‐ to quark‐matter transition. The results are compared to a previously published work with a similar model which uses, instead, a pairing approach to the optimization problem.

Limits on the diffuse flux of ultra-high energy neutrinos from the RICE experiment

Upper limits are presented on the diffuse flux of ultra-high energy neutrinos, based on analysis of data taken by the RICE experiment during August, 2000. The RICE receiver array at South Pole monitors cold ice for radio-wavelength Cherenkov radiation resulting from neutrino-induced in-ice showers. For energies above 1 EeV, RICE monitors over 25 km3 sr. We discuss limits based on both hadronic and electromagnetic showers.