A UV LED-based fast-pulsed photoelectron source for time-of-flight studies

TL;DR

This paper introduces a UV LED-based fast-pulsed photoelectron source capable of producing controlled electron pulses for calibration of high-resolution spectrometers in neutrino mass experiments.

Contribution

It presents a novel, adjustable, high-repetition-rate UV LED photoelectron source suitable for spectrometer calibration and time-of-flight studies.

Findings

Able to generate single to multiple photoelectrons per pulse

Pulse durations adjustable between 40 ns and 40 μs

Operates at repetition rates up to 10 kHz

Abstract

We report on spectroscopy and time-of-flight measurements using an 18 keV fast-pulsed photoelectron source of adjustable intensity, ranging from single photoelectrons per pulse to 5 photoelectrons per microsecond at pulse repetition rates of up to 10 kHz. Short pulses between 40 ns and 40 microseconds in length were produced by switching light emitting diodes with central output wavelengths of 265 nm and 257 nm, in the deep ultraviolet (or UV-C) regime, at kHz frequencies. Such photoelectron sources can be useful calibration devices for testing the properties of high-resolution electrostatic spectrometers, like the ones used in current neutrino mass searches.