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Neutron microscopes use neutrons to create images by nuclear fission of lithium-6 using small-angle neutron scattering. Neutrons are much heavier than photons and electrons used in forming photographic and X-ray images. Neutrons also have no electric charge, enabling them to penetrate substances to gain information about structure that is not accessible through other forms of microscopy. As of 2013, neutron microscopes offered four-fold magnification and 10-20 times better illumination than pinhole neutron cameras. The system increases the signal rate at least 50-fold. Neutrons interact with atomic nuclei via the strong force. This interaction can scatter neutrons from their original path and can also absorb them. Thus, a neutron beam becomes progressively less intense as it moves deeper within a substance. In this way, neutrons are analogous to x-rays for studying object interiors.〔 Darkness in an x-ray image corresponds to the amount of matter the x-rays pass through. The density of a neutron image provides information on neutron absorption. Absorption rates vary by many orders of magnitude among the chemical elements.〔 While neutrons have no charge, they do have spin and therefore a magnetic moment that can interact with external magnetic fields.〔 == Applications == Neutron imaging has potential for studying so-called soft materials, as small changes in the location of hydrogen within a material can produce highly visible changes in a neutron image.〔 Neutrons also offer unique capabilities for research in magnetic materials. The neutron's lack of electric charge means there is no need to correct magnetic measurements for errors caused by stray electric fields and charges. Polarized neutron beams orient neutron spins in one direction. This allows measurement of the strength and characteristics of a material's magnetism.〔 Neutron-based instruments have the ability to probe inside metal objects — such as fuel cells, batteries and engines to study their internal structure. Neutron instruments are also uniquely sensitive to lighter elements that are important in biological materials. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Neutron microscope」の詳細全文を読む スポンサード リンク
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