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

New Journal of Physics (Impact Factor: 3.56). 02/2009; 11(6). DOI: 10.1088/1367-2630/11/6/063018
Source: arXiv


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. Comment: 16 pages, 11 figures

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    • "The last two criteria on the list of requirements can be realised by two additional steps: (a) reducing the UV illumination to a small spot on the metal surface instead of using a wide-angle UV light beam, and (b) placing the photoelectron source in combined inhomogeneous electro-and magnetostatic fields. These two additional steps, which are new compared to the electron source presented in [13], will be described in detail in the following sections. "
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