Electron Emission in Superfluid and Low-temperature Vapor Phase Helium

TL;DR

This paper explains how tungsten filaments emit electrons efficiently in superfluid and low-temperature helium environments by analyzing changes in thermal transport, which resemble a first-order phase transition.

Contribution

It provides a novel explanation for electron emission in helium environments based on thermal transport mechanisms and phase transition analogy.

Findings

W tungsten filaments operate at high temperatures in 1 K helium environments.

Thermal transport changes enable electron emission at low temperatures.

Behavior resembles a first-order phase transition.

Abstract

Tungsten filaments used as sources of electrons in a low temperature liquid or gaseous helium environment have remarkable properties of operating at thousands of degrees Kelvin in surroundings at temperatures of order 1 K. We provide an explanation of this performance in terms of important changes in the thermal transport mechanisms. The behavior can be cast as a first-order phase transition.