Feasibility of a ’Brightness Booster’ for the Intense Slow Positron Source NEPOMUC

Abstract:

Brightness enhancement by re-moderation of highly intense slow positron sources at nuclear reactors or large electron accelerators is an inevitable requirement for most positron experiments. We demonstrate the feasibility of a new layout for re-moderation combining for the first time the high reliability of magnetic beam guiding, the high efficiency of reflection re-moderation, correction of spherical aberrations in the primary focussing lens and loss-free extraction of the re-moderated beam by an E x B-filter. In the case of the intense positron source NEPOMUC at the research reactor FRM II in Munich, up to 10-fold intensity and 100-fold brightness are predicted for the re-moderated positron beam, compared to the current situation.

• Periodical: Solid State Phenomena (Volume 374)
• Pages: 23-36
• DOI: https://doi.org/10.4028/p-LGc6vF
• Online since: July 2025
• Authors: Johannes Mitteneder*, Gottfried Kögel, Ricardo Helm, Marcel Dickmann, Günther Dollinger
• Keywords: Brightness Enhancement, Particle Optics, Positron Beam, Remoderation, Spherical Aberrations

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