Charged-particle beam accelerator

The invention relates to a charged-particle beam accelerator which emits a high-energy particle beam produced by accelerating along a circulating orbit a low-energy beam introduced from an ion source, as well as a particle beam radiation therapy system employing such a charged-particle beam accelerator and a method of operating the particle beam radiation therapy system.

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Patent

Publication date: Oct. 2006

Inventors: Tetsuya Nakanishi, Katsuhisa Yoshida, Masahiro Ikeda

Patent Application and description

Abstract:

The present invention relates to a charged-particle beam accelerator which emits a high-energy particle beam produced by accelerating along a circulating orbit a low-energy beam introduced from an ion source, as well as a particle beam radiation therapy system employing such a charged-particle beam accelerator and a method of operating the particle beam radiation therapy system.

A charged-particle beam accelerator includes an RF-KO unit for increasing the amplitude of betatron oscillation of a charged-particle beam within a stable region of resonance and an extraction quadrupole electromagnet unit for varying the stable region of resonance. The RF-KO unit is operated within a frequency range in which the circulating beam does not go beyond a boundary of the stable region of resonance, and the extraction quadrupole electromagnet unit is operated with appropriate timing as required for beam extraction so that the charged-particle beam is extracted with desired timing.

Current State of Research on Biological Effects of Terahertz Radiation

This is the post excerpt.

Authors: Gerald J. Wilmink (gerald.wilmink@us.af.mil), Jessica E. Grundt

Dated: 2011

Source: Air Force Research Lab, Fort Sam Houston, USA

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Abstract:

Terahertz (THz) imaging and sensing technologies are increasingly being used in a host of medical, military, and security applications. For example, THz systems are now being tested at international airports for security screening purposes, at major medical centers for cancer and burn diagnosis, and at border patrol checkpoints for identification of concealed explosives, drugs, and weapons. Recent advances in THz applications have stimulated renewed interest regarding the biological effects associated with this frequency range. Biological effects studies are a valuable type of basic science research because they serve to enhance our fundamental understanding of the mechanisms that govern THz interactions with biological systems. Such studies are also important because they often times lay the foundation for the development of future applications. In addition, from a practical standpoint, THz biological effects research is also necessary for accurate health hazard evaluation, the development of empirically-based safety standards, and for the safe use of THz systems. Given the importance and timeliness of THz bioeffects data, the purpose of this review is twofold. First, to provide readers with a common reference, which contains the necessary background concepts in biophysics and THz technology, that are required to both conduct and evaluate THz biological research. Second, to provide a critical review of the scientific literature.