Reflection of microwave from energy deposit by X-ray irradiation in rock salt: Implication of an ultra high energy salt neutrino detector to act like a radio bubble chamber

TL;DR

This study explores microwave reflection in rock salt caused by energy deposits from X-ray irradiation, proposing a novel method for detecting ultra high energy neutrinos using natural salt formations as radio bubble chambers.

Contribution

It demonstrates the feasibility of using microwave reflection in rock salt for ultra high energy neutrino detection, introducing a new radar-based detection method.

Findings

Reflection rate of 1x10^-6 at 1x10^19 eV energy deposit

Reflection proportional to square of X-ray intensity, indicating coherent scattering

Decay time of reflection lasted several seconds

Abstract

Existence of GZK neutrinos (ultra high energy neutrinos) have been justified although the flux is very low. A new method is desired to use a huge mass of a detector medium to detect them. A fundamental study of radar method was carried out to measure microwave reflection from electromagnetic energy deposit by X-ray irradiation in a small rock salt sample. The reflection rate of 1x10^-6 was found at the energy deposit of 1x10^19 eV which was proportional to square of the X-ray intensity suggesting the effect to be coherent scattering. The decay time of the reflection was several seconds. This effect implies a large scale natural rock salt formation could be utilized like a bubble chamber irradiated by radio wave instead of visible light to detect GZK neutrinos.