Continuous Radiation of braking

The continuous radiation of braking , or Bremsstrahlung (also called free-free emission in English), is a electromagnetic Rayonnement with broad spectrum created by the deceleration of electric charges. One also speaks about radiation Blanc .

When one bombards a solid target with a beam of electron S, those are slowed down and deviated by the Electric field of the cores of the target. However, according to the Maxwell's equations, any load of which speed varies, in absolute value or direction, rayon. As the deceleration of the electrons is not quantified, that creates a flow of Photon S whose spectrum in energy is continuous.

Form spectrum

The maximum energy of the photons is the kinetic energy initial E ₀ of the electrons. The spectrum in energy thus stops with this value E ₀. If one traces the spectrum in Wavelength (the most frequent representation), one has a spectrum which starts with λ₀ which is worth

$\backslash \; lambda\_0\; =\; \backslash \; frac\; \{hc\}\; \{E\_0\}$

or

$\backslash \; lambda\_0\; =\; \backslash \; frac\; \{hc\}\; \{E\; U\}$

and whose energy is maximum for λ_max which is worth

$\backslash \; lambda\_\; \backslash \; mathrm\; \{max\}\; =\; \backslash \; frac\; 3\; 2\; \backslash \; lambda\_0$

where

• H is the Constante of Planck;
• C is the Speed of light in the vacuum;
• E is the elementary electric Charge of the electron;
• U is the tension applied to the tube with x-rays.

Applications

This process is in particular used to produce x-rays, to see the articles Tube with x-rays and Synchrotron radiation .

Random links:

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