X-rays characteristics

X-Rays
X-rays are a form of electromagnetic radiation. They belong to the short-wavelength, high-frequency end of the electromagnetic spectrum, between the gamma and the ultraviolet radiation. They have wavelengths in the range of 10^-8m to 10^-10m. Their frequency range is 3x10^16Hz to 3x10^19Hz. X-rays are produced by the movement of electrons in atoms. When a photon collides with another atom, the atom may absorb the photon’s energy causing an electron to jump to a higher energy level. This can only happen if the energy level of the photon matches the energy difference between the two electron levels. The electron then falls back to its original energy level, releasing the extra energy in the form of a light photon.

The soft tissue in our body is composed of atoms that do not absorb x-ray photons very well, because their energy levels do not match the energy of the photons. However, the bone tissue absorbs these same photons quite well, due to the calcium atoms which have higher energy levels between its atoms that match the photons energy.

There are two types of X-rays, according to their photon energy:

1. Soft x-rays

These x-rays are defined by having photon energies below 10keV. They have less energy than the hard x-rays, therefor they have higher wavelength. Soft x-rays are used in radiography to take pictures of bones and internal organs. Because they have a relatively low frequency, they do not cause much damage to tissues, unless they are repeated too often.

2. Hard x-rays

Hard x-rays have photon energies above 10 keV. They have smaller wavelength than the soft x-rays. These x-rays are used in radiotherapy, a treatment for cancer. Due to their high frequency, they destroy molecules within specific cells, thus destroying tissue. Another use for these x-rays is airport security. Hard x-rays are used in security scanners to examine baggage.