New Delhi, Nov 8:The search engine giant Google has boasted a X-Ray doodle on its home page to celebrate the 115th anniversary of its invention. The X-Ray design was created by German physics professor Wilhelm Rontgen on Nov 8, 1985.
The X-Ray doodle is a cool blue neon design. The logo also shows a glow of radiation from the each letter of 'Google'. On clicking on the doodle, users can see search results for X-Ray.
Wilhelm Conrad Roentgen invented X-Rays accidentally when he was experimenting with vacuum tubes. A week later, he took an X-ray photograph of his wife's hand which clearly revealed her wedding ring and her bones.
The photograph electrified the general public and aroused great scientific interest in the new form of radiation.
Roentgen called it 'X' to indicate it was an unknown type of radiation. But still in some German-speaking countries it is referred as Roentgen rays.
So many other scientists like Ivan Pulyui, William Crookes, Johann Wilhelm Hittorf etc were also contributed to the study of X-rays.
X-rays from about 0.12 to 12 keV (10 to 0.10 nm wavelength) are classified as "soft" X-rays, and from about 12 to 120 keV (0.10 to 0.01 nm wavelength) as "hard" X-rays, due to their penetrating abilities.
Hard X-rays can penetrate solid objects, and their most common use is to take images of the inside of objects in diagnostic radiography and crystallography. As a result, the term X-ray is metonymically used to refer to a radiographic image produced using this method, in addition to the method itself. By contrast, soft X-rays can hardly be said to penetrate matter at all; for instance, the attenuation length of 600 eV (~ 2 nm) x-rays in water is less than 1 micrometer.X-rays are a form of ionizing radiation, and exposure to them can be a health hazard.
The distinction between X-rays and gamma rays has changed in recent decades. Originally, the electromagnetic radiation emitted by X-ray tubes had a longer wavelength than the radiation emitted by radioactive nuclei (gamma rays). Older literature distinguished between X- and gamma radiation on the basis of wavelength, with radiation shorter than some arbitrary wavelength, such as 10−11 m, defined as gamma rays. However, as shorter wavelength continuous spectrum "X-ray" sources such as linear accelerators and longer wavelength "gamma ray" emitters were discovered, the wavelength bands largely overlapped. The two types of radiation are now usually distinguished by their origin: X-rays are emitted by electrons outside the nucleus, while gamma rays are emitted by the nucleus.
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