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The Bremsstrahlung effect happens when an electron is decelerated by changing its direction typically around a nucleus and then a photon beam is released.

We know that when a scattering happens, let's say Compton scattering, the particle nature of the photon presents itself and the photon hit a free (or valance) electron like a billiard ball then they change courses of motion with different energies and angles.

Now the change in the direction of motion is a change in the direction of the velocity of the electron, which results in the acceleration (or let's say deceleration of a moving electron) of that electron. So this looks like a very quick, sudden and short Bremsstrahlung as in a quick change in motion of an electron when the scattering happens.

If you say that accelerating an electron does not cause an electron to create Bremsstrahlung radiation, you can think this Compton scattering as one of the decelerating types: Incident electron hits a moving electron with a constant velocity and decelerates it or much better changes its direction of motion (acceleration again caused by the change in direction of motion).

Does this cause Bremsstrahlung then because of the same logical assessment?

I mean, is this way of thinking correct? Does Bremsstrahlung happen when any type of scattering happens?

EDIT: Wikipedia : "Broadly speaking, bremsstrahlung or braking radiation is any radiation produced due to the deceleration (negative acceleration) of a charged particle, which includes synchrotron radiation (i.e., photon emission by a relativistic particle), cyclotron radiation (i.e. photon emission by a non-relativistic particle), and the emission of electrons and positrons during beta decay. However, the term is frequently used in the more narrow sense of radiation from electrons (from whatever source) slowing in matter." en.wikipedia.org/wiki/Bremsstrahlung

This link says that acceleration of a charged particle causes Bremsstrahlung radiation also: astro.utu.fi/~cflynn/astroII/l3.html

medical physics
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Bremsstrahlung means braking radiation, and involves at least two charged bodies - the body that is braking (e.g. an electron), and the body that causes the braking (e.g. a nucleus, or a group of them).

Various EM radiation scattering scenarios do not have to involve two charged bodies - the radiation would be scattered already by a single charged body (e.g. an electron).

Both bremsstrahlung and EM wave scattering involve at least one accelerated charged body.

EM wave scattering off one charged body is not bremsstrahlung, and does not involve bremsstrahlung.

Bremsstrahlung is not a scattering of an existing radiation, but creation of new radiation.

Accelerated charged particle radiates changes in EM field, and EM field can be ascribed some energy. Changed EM field means changed energy of EM field.

In classical EM theory, scattering of an existing radiation means that electron changes its velocity (in quantum EM theory, electron field changes its state) and produces new (secondary) radiation. Superposition of the primary and secondary radiation is total radiation that can be observed. In the simplified billiard model, the scattered photon is a new photon, and the old photon disappears.

Ján Lalinský
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It's all kind of arbitrary. Thomson's classical scattering calculation was based on the acceleration of an electron by electromagnetic waves. Then, in the Compton effect is the outgoing photon the "same" as the incoming one? It's not something that an experiment can decide, so it's not a proper physical question.

Nature doesn't care about how we classify phenomena.

John Doty
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There is a lot of misleading and confusing information out there regarding Bremsstrahlung. This is because there really are two definitions - a broad one and a narrow one, and they are all too often conflated. Allow me to elucidate on the broad one.

Bremsstrahlung is created by the acceleration of any charged body. Classically, this can be understood from creating a time-dependence in the electric field emitted by that body. As a time-dependent electric field creates a time-dependent magnetic field, and vice versa, this results in the propogation of radiation emitted from the charge. This happens regardless of the cause of acceleration.

Yes, quantum mechanics provides its own description, but it ultimately results in some spectral variance, not a total change in whether the emission occurs at all (bound states being a special case, that I'm not going to get into).

This means that bremsstrahlung is the result of any interaction that results in an acceleration on a charge. This includes all scattering events, Lorentz force interactions, gravitational interactions, and so on.

Logan J. Fisher
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