Amor - Selene

Selene is the attempt to implement a new scheme for high-intensity specular reflectometry. Instead of a highly collimated beam one uses a convergent beam covering a large angular range. The resolution of qz is performed on by an position sensitive detector. Off-specular scattering in this set-up leads to some background, but for screening of wide parameter ranges (e.g. temperature, electric and magnetic fields) the intensity gain of at least one order of magnitude is essential. The following high precision measurements (even with off-specular components) is then performed with the conventional set-up.

Sketch of Amor in the scattering plane with the test set-up for selene. The colour code is: black: diaphragms, absorber; blue: auxiliary lines and reference beam; red: (coated) guide; yellow: (part of) beam. The vertical axis is stretched by a factor of 10.
Sketch of Amor in the scattering plane with the test set-up for selene. The colour code is: black: diaphragms, absorber; blue: auxiliary lines and reference beam; red: (coated) guide; yellow: (part of) beam. The vertical axis is stretched by a factor of 10.

The heart of this new set-up is an elliptically focusing guide element of 2 m length. Though this guide is optimised for the use on the TOF reflectometer Amor at SINQ, it can be used as stand-alone device to check the possible application for other neutron scattering techniques on various instruments also.

The ideas behind selene are published by F. Ott and A. Menelle (N.I.M. A 586, 23, 2008; European Physical Journal 167, 93, 2009) and by J. Stahn et al. (N.I.M. A, in press 2010, doi:10.1016/j.nima.2010.06.221). The present state of the project is documented in the report the selene project. A manuscript reporting on the first tests can be found at arXiv:1102.2747 [physics.ins-det].