title: Tuning the instrument resolution using chopper and time of flight at the small-angle neutron scattering diffractometer KWS-2.
abstract: Following demand from the user community regarding the possibility of improving the experimental resolution, the dedicated high-intensity/extendedQ-range SANS diffractometer KWS-2 of the Jülich Centre for Neutron Science at the Heinz Maier-Leibnitz Center in Garching was equipped with a double-disc chopper with a variable opening slit window and time-of-flight (TOF) data acquisition option. The chopper used in concert with a dedicated high-intensity velocity selector enables the tuning at will of the wavelength resolution Δλ/λ within a broad range, from 20% (standard) down to 2%, in a convenient and safe manner following pre-planned or spontaneous decisions during the experiment. The new working mode is described in detail, and its efficiency is demonstrated on several standard samples with known properties and on a completely new crystallizable copolymer system, which were investigated using both the conventional (static) and TOF modes.
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Outstation at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany.
authors.forename: Aurel
authors.initials: A
authors.lastname: Radulescu
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Outstation at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany.
authors.forename: Noémi Kinga
authors.initials: NK
authors.lastname: Székely
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Polachowski
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Marko
authors.initials: M
authors.lastname: Leyendecker
authors.affiliation: Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Amann
authors.affiliation: Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Johan
authors.initials: J
authors.lastname: Buitenhuis
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Drochner
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Engels
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Romuald
authors.initials: R
authors.lastname: Hanslik
authors.affiliation: Zentralinstitut für Engineering, Elektronik und Analytik (ZEA), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Günter
authors.initials: G
authors.lastname: Kemmerling
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble, 38000, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Lindner
authors.affiliation: Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, Athens, 11635, Greece.
authors.forename: Aristeidis
authors.initials: A
authors.lastname: Papagiannopoulos
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Outstation at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany.
authors.forename: Vitaliy
authors.initials: V
authors.lastname: Pipich
authors.affiliation: Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Willner
authors.affiliation: Jülich Centre for Neutron Science (JCNS), Outstation at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstrasse 1, Garching, 85747, Germany.
authors.forename: Henrich
authors.initials: H
authors.lastname: Frielinghaus
authors.affiliation: Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Jülich GmbH, Jülich, 52425, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Richter
keywords: small-angle neutron scattering (SANS); time of flight; wavelength spread