X-ray

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An X-ray tube. Electrons �boil� off the cathode when the filament is heated by a �
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Electromagnetic radiation of extremely short wavelength (100 nanometres to 0.001 nanometre) produced by the deceleration of charged particles or the transitions of electrons in atoms.

X-rays travel at the speed of light and exhibit phenomena associated with waves, but experiments indicate that they can also behave like particles (see wave-particle duality). On the electromagnetic spectrum, they lie between gamma rays and ultraviolet radiation. They were discovered in 1895 by Wilhelm Conrad Röntgen, who named them X-rays for their unknown nature. They are used in medicine to diagnose bone fractures, dental cavities, and cancer; to locate foreign objects in the body; and to stop the spread of malignant tumours. In industry, they are used to analyze and detect flaws in structures.

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$grazing incidence: refraction of light rays in an X-ray telescope$

More on "X-ray" from Britannica Concise:

X-ray diffraction - Phenomenon in which the atoms of a crystal, by virtue of their uniform spacing, cause an interference pattern of the waves in an incident beam of X-rays.

X-ray astronomy - Study of astronomical objects and phenomena that emit radiation at X-ray wavelengths.

gamma ray - Penetrating very short-wavelength electromagnetic radiation, similar to an X-ray but of higher energy, that is emitted spontaneously by some radioactive substances (see gamma decay; radioactivity).

gamma-ray astronomy - Study of astronomical objects and phenomena that emit gamma rays.

diagnostic imaging - Use of electromagnetic radiation to produce images of internal body structures for diagnosis. X-rays have been used since 1895.

More on "X-ray" from the 32 Volume Encyclopædia Britannica:

X-ray - electromagnetic radiation of extremely short wavelength and high frequency, with wavelengths ranging from about 108 to 1012 metre and corresponding frequencies from about 1016 to 1020 hertz (Hz).

X-ray tube - evacuated electron tube that produces X rays by accelerating electrons to a high velocity with a high-voltage field and causing them to collide with a target, the anode plate. The tube consists of a source of electrons, the cathode, which is usually a heated filament, and a thermally rugged anode, usually of tungsten, which is enclosed in an evacuated glass envelope. The voltage applied to ...

X-ray source - in astronomy, any of a class of cosmic objects that emit radiation at X-ray wavelength. Because the Earth's atmosphere absorbs X rays very efficiently, X-ray telescopes and detectors must be carried high above it by spacecraft to observe objects that produce such electromagnetic radiation.

X-ray telescope - instrument designed to detect and resolve X rays from sources outside the Earth's atmosphere. Because of atmospheric absorption, X-ray telescopes must be carried to high altitudes by rockets or balloons or placed in orbit outside the atmosphere. Balloon-borne telescopes are used to detect the more penetrating (harder) X rays, whereas those carried aloft by rockets or in satellites are used to ...

X-ray style - manner of depicting animals by drawing or painting the skeletal frame and internal organs. It is one of the characteristic styles of the art of some prehistoric hunting cultures.

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