The absorption edges accessible on SIRIUS are complementary to those accessible on SAMBA, SIXS and SEXTANTS: on SIRIUS, it is the soft X-rays range that is covered (1.4 – 11 keV). This range is of interest particularly to scientists in the field of soft materials (Ca, Cl, Cd, S, P, K…), semi-conductors (K-edges of P, Si, Al, L-edges of In, Sb) and magnetism (L-edge, M-edge of 4d-5d elements, K-edge of 3d elements).
This complementarity between the lines is also reflected in the choice of equipment for SIRIUS. Indeed, besides the diffractometer which should satisfy the needs of most users of SIRIUS, the "RESOXS" reflectometer of SEXTANTS, which allows the magnetic properties of nanoparticles to be analyzed by X-ray resonant magnetic scattering (XRMS), can be installed on SIRIUS. RESOXS will therefore spend a few weeks each year in the SIRIUS experimental hutch to make higher energy measurements than on SEXTANTS.
In addition, the light source (Apple II HU 36 undulator- the first to be installed on a short section of the storage ring, and having an equally short period) and one of the two SIRIUS monochromators was selected in order to modulate the polarization of the synchrotron radiation produced: the latter can be horizontal or vertical linear, but also circular. The monochromator that maintains the circular polarization will use multilayer gratings at very shallow groove depths and variable period. This instrument is also unique for the moment, as the grating technology that underlies its operation is usually reserved for lower energies.
