"Radio Interactions with Particle-Shower Plasmas, and Implications for High-Energy Astroparticle Physics" by Steven Prohira (University of Kansas)

Wednesday, November 8, 2017 - 12:00pm to 1:00pm
HEAP Seminar

The collision of a high-energy particle with stationary matter, such as ice, results in a shower of subsequent particles. As these subsequent particles traverse the interaction medium, cold ionization electrons are produced. For high enough primary particle energies, this cloud of ionization electrons is dense enough to form a tenuous plasma which may reflect radio-frequency (RF) energy. As such, RF scatter techniques have been proposed as a robust technology to remotely detect such high-energy particle interactions by illuminating a detection volume with RF energy and remotely monitoring the same volume for a reflected RF signal from a particle-shower plasma. Though the Telescope Array RADAR (TARA) experiment, the first dedicated attempt at the radio-scatter method for cosmic rays, yielded no results, the intriguing lack of signal has caused renewed interest in the technique. Surprisingly, a dedicated laboratory measurement of RF scatter from particle-showers has never been performed at high (GeV) energies. This talk will discuss experimental results from TARA and will detail a laboratory measurement to take place at the End-Station facilities at SLAC to quantify the parameters of the particle-shower plasma. A high-energy electron beam will be fired into a large target to initiate a shower from which RF will be reflected. The simulations for and observables from this measurement will be discussed, along with outlook.

Event Attachments: 
Knudsen 4-134