Nested mirror optics – the next generation of neutron delivery systems?

General ILL webinar 

Organised by College 3

Tuesday, 29 March 2022 at 11h00

Zoom link: //ill.zoom.us/j/91652569125?pwd=RXJKOEU2UEhuTkc4cWkrTFBUdmdadz09
Passcode: 170452

“Nested mirror optics – the next generation of neutron delivery systems?”

Oliver Zimmer

ILL, Grenoble, France, zimmer@ill.fr

Upcoming high-brilliance neutron moderators at the ESS and elsewhere have raised the question what might be the most efficient method to extract neutrons from such small sources and how to transport them with best possible brilliance transfer to an instrument. Nested mirror optics (NMO) offer a viable and flexible solution. Consisting of an assembly of short elliptic mirrors, such systems are able to map, with low loss of intensity, a large and well-defined volume of beam phase space from the moderator surface to a target, such as a sample or a virtual source. In contrast to neutron guides, each mirror of an NMO reflects neutrons within a narrow range of finite angles, which enables a precise tailoring of the beam divergence and spectrum to the needs of experiments. The device produces a clean beam without optical elements close to the source and the target, which leads to a number of practical advantages. After a presentation of the concept, this talk will report results of a recent experiment performed with an NMO prototype at the neutron reflectometer MIRA at FRM2, and discuss potential applications of NMO for neutron scattering and fundamental physics.

[1] O. Zimmer, Imaging nested-mirror assemblies – a new generation of neutron delivery systems?, J. Neutron Research 20 (2018), 91-98.
[2] C. Herb, O. Zimmer, R. Georgii, P. Böni, Nested mirror optics for neutron extraction, transport, and focusing, 2022, arXiv:2202.07899.

Caterina Michelagnoli (College 3 Secretary)