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Cool4Kat
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i know that x-rays are produced when a beam of high energy electrons hits a metal anode but why does that work better than when that same beam hits glass (like in the Crookes tube)?
Thanks
Thanks
mjc123 said:When an energetic electron hits an atom it can knock out a core electron. Then one of two things can happen:
(i) An electron from a higher shell can fall into the vacancy in the lower shell, accompanied by the emission of an X-ray photon.
(ii) An electron from a higher shell can fall into the vacancy in the lower shell, while another outer electron is expelled from the atom (Auger electron).
The quantum yield of X rays increases with atomic number; light elements give mostly Auger electrons and heavy elements mostly X rays. The crossover is somewhere around zinc (Z = 30). Thus glass, containing mainly Si and O, will give a lower yield of X rays than a heavier metal, such as iron or tungsten.
Thus much I know from my acquaintance with SEM. Why things are that way round, I don't know.
Metal is commonly used to produce x-rays because it has a higher atomic number than glass, which allows for a higher production of x-ray photons. This makes metal more efficient for producing x-rays.
Metal has a higher density than glass, which means it can produce more x-rays per unit of volume. This makes it more efficient for producing x-rays, as less material is needed to create the same amount of x-rays.
Yes, glass can be used to make x-rays, but it is not as efficient as metal. Glass has a lower atomic number and density, which means it produces fewer x-rays and requires more material to produce the same amount of x-rays as metal.
One disadvantage of using metal for x-rays is that it can be more expensive than glass. Additionally, some metals can be toxic, which can be a safety concern for workers handling the equipment.
Yes, glass and metal can be used together to make x-rays. In some cases, a combination of materials may be used to take advantage of their unique properties and produce more efficient x-rays.