Radio-quiet neutron star Radio-quiet neutron star A radio-quiet neutron star is a neutron star that does not seem to emit radio emissions, but is still visible to Earth through electromagnetic radiation at other parts of the spectrum, particularly x-rays and gamma rays. Most detected neutron stars are pulsars, and emit radio-frequency electromagnetic radiation. About 700 radio pulsars are listed in the Princeton catalog, and all but one emit radio waves at the 400 MHz and 1400 MHz frequencies. That exception is Geminga, which is radio quiet at frequencies above 100 MHz, but is a strong emitter of X-rays and gamma rays. In all,
Electron-beam welding if needed. In micro-electron beam devices, components with dimensions in tenths of a millimeter can be precisely welded. In welders with electron beams of high enough power, welds up to 300 mm deep can be realized. There are also welding machines in which the electron beam is brought out of vacuum into the atmosphere. With such equipment very large objects can be welded without huge working chambers. Electron-beam welding can never be "hand-manipulated", even if not realized in vacuum, as there is always strong X-radiation. The relative motion of the beam and the workpiece is most often achieved by rotation