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Roentgen Radiation

Roentgen Radiation Roentgen radiation is a type of electromagnetic radiation. It is different from other types, for example, from a visible light, primarily in its frequency and wave length bands. This type of radiation has wave length from 10(-14th) to 10(-8th) power meter. It is located on the electromagnetic wave spectrum between ultraviolet and gamma radiation. With the latter type it has equivalent radiation at the identical photon energy. But their principles of wave occurrence are different. These rays were discovered in 1895 by a German physicist Roentgen. Both in Germany and Russia they are known as Roentgen rays. However, in many other countries they are known as X-rays. X-rays are generated at a high acceleration and a subsequent slowing-down of charged particles or at a transition of particles in electron shells of atoms which is also accompanied by emission of radiation. In practice this is carried out in X-ray tubes. There are two electrodes - anode and cathode. Under the influence of magnetic field the electrons accelerate and move towards the anode. When colliding with it they abruptly decelerate, and roentgen radiation is emitted. Electrons which break away from atom shells are replaced by other electrons of the atom. Depending on the anode's material radiation of a corresponding energy spectrum occurs. Most often the anode is ceramic while the spot into which electrons crash is made of molybdenum or tungsten. It also heats up as the greater portion of energy is spent on heat and only a small portion is spent on wave generation. Properties of X-rays are conditioned by their small wave length which is comparable with atom size. They practically do not reflect from other surfaces. Diamond is the only exception. It is also almost impossible to focus them with optical devices. They easily pass through a substance while various substances absorb X-rays differently. This effect allowed to use X-rays in common practice. X-rays just like visible light can expose a photographic film. This is one of the ways to register them while exposure is stronger in places of higher radiation intensity. But again, radiation intensity during exposure depends on the strength of the substance through which rays pass. Absorption rate depends exponentially on the thickness of absorbing layer as well as on wave length of the element and what is most important on the atomic number of the absorbing substance. It is different for various substances thus emitted flux turns out to be intensity-modulated. This results in image build-up on the film during its exposure.This is the principle of roentgenography. Internal structure of objects can be examined with its help. The principle is used in various technical tasks and industry for assessing structure of components and constructions. But the most popular area of its application is of course medicine. Soft tissues and bones absorb Roentgen radiation differently thus when X-raying body we can receive the image of skeleton.It is also important to remember that X-rays have a negative biological impact on our organisms. They can cause malignant tumours, radiation sickness or burns, and various mutations. That is why we should avoid exposure to such radiation or have it only in limited amounts.Nevertheless, X-rays occurring at atoms' ionization or coming from space and not absorbed by the atmosphere are constantly present in the environment. But don't be afraid. This natural dosage is very small and will not harm you.