Radio-quiet neutron star ten bodies have been proposed as rotation-powered neutron stars that are not visible as radio sources, but are visible as x–ray and gamma ray sources. Indicators that they are indeed neutron stars include them having a high x-ray to lower frequencies emission ratio, a constant x-ray emission profile, and coincidence with a gamma ray source. Quark stars, theoretical neutron star-like objects composed of quark matter, may be radio quiet, according to some theories. More plausibly, however, radio-quiet neutron stars may simply be pulsars which do not pulse in our direction. As pulsars spin, it is theorized they emit radiation from
Neutron radiation highly penetrating and damaging nature to cellular structure. Neutrons can also be used for imaging of industrial parts termed neutron radiography when using film, neutron radioscopy when taking a digital image, such as through image plates, and neutron tomography for three-dimensional images. Neutron imaging is commonly used in the nuclear industry, the space and aerospace industry, as well as the high reliability explosives industry. Neutron radiation is often called "indirectly ionizing radiation". It does not ionize atoms in the same way that charged particles such as protons and electrons do (exciting an electron), because neutrons have no charge. However, neutron