MLZ is a cooperation between:> Technische Universität München> Helmholtz-Zentrum Geesthacht> Forschungszentrum Jülich
The Neutron Optics group takes care of the neutron guide systems at the FRM II. Our duties beyond maintenance and repair of the existing neutron guides are the acquisition or production of new guide elements, support for the acquisition of crystal monochromators and the supply of spin-polarized 3He for neutron-spin-filters. Within this scope we run a DC magnetron sputtering device for the production of supermirrors, the 3He spin polarizing system HELIOS and in cooperation with our partner JCNS the neutron reflectometer TREFF.
We have facilities for all production steps of neutron guide elements in house. Shaping of the raw float glass plates is done with a precision diamond saw. The plates with a length up to 1m are coated with Ni/Ti supermirrors with m values up to m = 3.5 in our DC magnetron sputtering facility. The neutron optical properties of the individual mirror plates are verified with our neutron reflectometer TREFF. Precision benches serve for the assembly of the up 2.5 m long guide elements.
Using either our neutron guide elements or ones purchased from other manufactures we build up the neutron guide for the instruments. For the alignment of the guide elements we use either total stations or a laser tracker system. Particular care is taken of radiation shielding optimization to provide a low background inside the neutron guide halls.
HELIOS is a MEOP (metastability exchange optical pumping) station for the production of polarised 3He gas, which is used by several instruments at the MLZ to perform neutron polarisation analysis. In addition to the continuous work on improving and optimising the HELIOS facility to reach highest degree of polarisation, we support the MLZ instruments by developing glass vessels for 3He to be introduced into the instrumental neutron beam-line, and specific magnetic cages to maintain very homogeneous magnetic fields across the 3He volume.
In collaboration with JCNS we operate the general-purpose neutron reflectometer TREFF at the neutron guide NL5-S. A PG(002) double monochromator with fixed scattering angles of 90° provides a monochromatic beam with a wavelength of λ = 4.8 Å. (2.4 Å / PG 004). Equipped with a position sensitive detector and polarization analysis, the instrument is ideally suited for multilayer characterization (i.e. our supermirror coatings), Bragg crystals and for high resolution reflectometry with polarized neutrons in general.
Dr. Peter Link
Phone: +49 (0)89 289-14622
Dipl. Ing. Christian Breunig
Phone: +49 (0)89 289-14593
Dr. Sergey Masalovich
Phone: +49 (0)89 289-14559
Dipl. Ing. Andreas Ofner
Phone: +49 (0)89 289-14677