title: Ultracold neutron detectors based on10B converters used in the qBounce experiments.
abstract: Gravity experiments with very slow, so-called ultracold neutrons connect quantum mechanics with tests of Newton's inverse square law at short distances. These experiments face a low count rate and hence need highly optimized detector concepts. In the frame of this paper, we present low-background ultracold neutron counters and track detectors with micron resolution based on a10B converter. We discuss the optimization of10B converter layers, detector design and concepts for read-out electronics focusing on high-efficiency and low-background. We describe modifications of the counters that allow one to detect ultracold neutrons selectively on their spin-orientation. This is required for searches of hypothetical forces with spin-mass couplings. The mentioned experiments utilize a beam-monitoring concept which accounts for variations in the neutron flux that are typical for nuclear research facilities. The converter can also be used for detectors, which feature high efficiencies paired with high spatial resolution of [Formula: see text]. They allow one to resolve the quantum mechanical wave function of an ultracold neutron bound in the gravity potential above a neutron mirror.
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria.
authors.forename: Tobias
authors.initials: T
authors.lastname: Jenke
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria.
authors.forename: Gunther
authors.initials: G
authors.lastname: Cronenberg
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria.
authors.forename: Hanno
authors.initials: H
authors.lastname: Filter
authors.affiliation: Institut Laue-Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Geltenbort
authors.affiliation: Physikalisches Institut Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Klein
authors.affiliation: FRM II, TU München, Lichtenbergstraße 1, 85748 Garching, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Lauer
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria.
authors.forename: Kevin
authors.initials: K
authors.lastname: Mitsch
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria ; FRM II, TU München, Lichtenbergstraße 1, 85748 Garching, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Saul
authors.affiliation: Physik Department, TU München, James-Franck-Straße, 85748 Garching, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Seiler
authors.affiliation: Physikalisches Institut Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Stadler
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Thalhammer
authors.affiliation: Atominstitut TU Wien, Stadionallee 2, 1020 Wien, Austria ; Physikalisches Institut Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany ; Physik Department, TU München, James-Franck-Straße, 85748 Garching, Germany.
authors.forename: Hartmut
authors.initials: H
authors.lastname: Abele
keywords: 10-B converter; Low-background UCN counter; Micron-resolution track detector; Ultracold neutron detector; qBounce
references.citation: Nature. 2002 Jan 17;415(6869):297-9
references.pmid: 11797001
references.citation: Nucl Instrum Methods Phys Res A. 2013 Dec 21;732:1-8
references.pmid: 25843998