Dosimetry of a novel focused monoenergetic beam for radiotherapy.

. A novel treatment modality is currently being developed that produces converging monoenergetic x-rays. Conventional application of dosimetric calibration as presented in protocol TG61 is not applicable.

Analysis of a novel X-ray lens for converging beam radiotherapy.

We describe the development and analysis of a new teletherapy modality that, through a novel approach to targeted radiation delivery, has the potential to provide greater conformality than conventional photon-based treatments. The proposed system uses an X-ray lens to reflect photons from a conventional X-ray tube toward a focal spot. The resulting dose distributions have a highly localized peak dose, with lower doses in the converging radiation cone.

Stability of the antiferromagnetic state in the electron doped iridates.

Iridates such as SrIrO are of considerable interest owing to the formation of the Mott insulating state driven by a large spin-orbit coupling. However, in contrast to the expectation from the Nagaoka theorem that a single doped hole or electron destroys the anti-ferromagnetic (AFM) state of the half-filled Hubbard model in the large U limit, the anti-ferromagnetism persists in the doped Iridates for a large dopant concentration beyond half-filling. With a tight-binding description of the relevant [Formula: see text] states by the third-neighbor (t , t , t , U) Hubbard model on the square lattice, we examine the stability of the AFM state to the formation of a spin spiral state in the strong coupling limit.