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@danielpelliccia@aus.social · 5 months ago

OK, one of key features of our book on #Synchrotron Light is that it considers a broader context for synchrotron sources, by no means limited to particle accelerators.

In the book we discuss three generalisations:

1. Synchrotron radiation is not exclusive to accelerators. In fact, synchrotron emission "dominates much of high-energy #astrophysics" (quoting Longair's High Energy Astrophysics book)

2. The accelerating force must not be necessarily electromagnetic. For instance, an electron accelerated by the gravitational force of a black hole (by virtue of its mass) will produce synchrotron emission (by virtue of its electric charge)

3. The particle radiation mechanism must not be necessarily electromagnetic. Example: electron radiation of Z0 particles mediated by the weak interaction is equivalent to (conventional) synchrotron photon emission by electromagnetic interaction as in the figure. This is true since the unification of the electromagnetic and weak forces, any electromagnetic interaction involving a photon (a vertex in a Feynman diagram) can have that photon replaced by a Z 0 gauge boson

#physics

4/N

Two Feynman diagram representing two equivalent processes in the electro-weak theory.

In the top diagram, an electron (drawn as a solid line with an arrow directed from left to right), emits a photon at the point P1. The photon is drawn as a squiggly line outgoing from P1 to the upper-right direction. The electron recoils from P1 toward the lower-right direction.

In the botton diagram there is the equivalent process whereby an electron emits a Z0 gauge boson at the point P2 and recoils towards the lower-right direction. The Z0 boson travels towards the upper left and eventually decays at the point P3 emitting two muons of opposite electric charge (denoted by solid lines) diverging from P3 towards the right direction. — Two Feynman diagram representing two equivalent processes in the electro-weak theory. In the top diagram, an electron (drawn as a solid line with an arrow directed from left to right), emits a photon at the point P1. The photon is drawn as a squiggly line outgoing from P1 to the upper-right direction. The electron recoils from P1 toward the lower-right direction. In the botton diagram there is the equivalent process whereby an electron emits a Z0 gauge boson at the point P2 and recoils towards the lower-right direction. The Z0 boson travels towards the upper left and eventually decays at the point P3 emitting two muons of opposite electric charge (denoted by solid lines) diverging from P3 towards the right direction.

Daniel Pelliccia

@danielpelliccia@aus.social replied · 5 months ago

Synchrotron light is conventionally defined as the emission from accelerated ultra-relativistic electric charges.

Ultra-relativistic means that the speed of the charge is extremely close to the speed of light, v ≈ c.

The first part of the book deals with introductory concepts, starting from special relativity, and moving on emission from accelerated charges, then #synchrotron emission from charges in circular and undulating trajectories.

2/N

#Physics #Electrodynamics #books #PhysicsBooks

Daniel Pelliccia

@danielpelliccia@aus.social replied · 5 months ago

Quite surprisingly, most of the properties of (classical) synchrotron radiation were worked out by G.A. Schott in1907--1912 in his dissertation work.

Working in a 'pre-quantum' world, Schott wanted to explain the observed lines in the emission #spectra of atoms. He started with a ‘Rutherford-like' atomic model where point electrons move in closed orbits around a nucleus: what would the emission spectra of such accelerated particles be like?

Starting from these premises, Schott derived the emission spectrum of (what we know today as) synchrotron light!

As we understand today, the motion of bound electrons cannot be explained by classical #Electrodynamics. Schott's formulas didn't work in describing atomic spectra and his work was forgotten for a while, only to be rediscovered in the 1940s when the first synchrotron machines were being built.

Now, electrons moving on macroscopic curved trajectories are extremely well described by classical electrodynamics, and Schott's formulas work exceedingly well in predicting the properties of #synchrotron light.

#physics

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The front page of the "London, Edinburgh and Dublin Philosophical Magazine and Journal of Science" dated February 1907. The page shows a scientific article by G.A. Schott titled "On the electron theory of matter and on radiation". The articles begins with the following words: "One of the most important problems of the Electron Theory of Matter is to account for the spectra emitted by the several elements; the solution of this problem, rather than of any other, seems likely to lead to the construction of a working model of the atom."

Daniel Pelliccia

@danielpelliccia@aus.social replied · 5 months ago

OK, one of key features of our book on #Synchrotron Light is that it considers a broader context for synchrotron sources, by no means limited to particle accelerators.

In the book we discuss three generalisations:

1. Synchrotron radiation is not exclusive to accelerators. In fact, synchrotron emission "dominates much of high-energy #astrophysics" (quoting Longair's High Energy Astrophysics book)

#physics

4/N

Daniel Pelliccia

@danielpelliccia@aus.social replied · 21 hours ago

Extra learning material for our Synchrotron Light book is freely available at
https://synchrotron-light.net

There's all the figures, links to most references, #python scripts and other bonus material.

#synchrotron #physics #books #physicsBooks

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