Compton Scattering and Inverse Compton Scattering

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Discussion Overview

The discussion centers on the relationship between Compton scattering and inverse Compton scattering, particularly in the context of finding a general equation that can predict the occurrence of these processes. Participants explore the theoretical underpinnings and applications of these scattering phenomena, with references to specific processes like the nonlinear Breit-Wheeler process.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants inquire about a general equation that could determine whether an electron will undergo Compton or inverse Compton scattering.
  • Others suggest that understanding the cross sections for these processes is essential for determining probabilities of scattering events.
  • A participant mentions the Klein-Nishina formula as potentially relevant to their inquiry about scattering processes.
  • Inverse Compton scattering is described as involving low energy photons being scattered to high energies by ultrarelativistic electrons, with implications for stellar atmospheres and electron beam accelerators.
  • The nonlinear Breit-Wheeler process is discussed as a mechanism for electron-positron pair production from photon collisions, with references to its theoretical and experimental aspects.
  • Some participants express uncertainty about the practical realization of the processes discussed, particularly in relation to producing a gamma-ray laser.

Areas of Agreement / Disagreement

Participants express various viewpoints regarding the equations and processes involved, with no clear consensus on a single general equation or method for determining scattering outcomes. The discussion remains unresolved with competing ideas and interpretations.

Contextual Notes

Participants mention the need for specific energy considerations and the relevance of cross sections, indicating that assumptions about energy levels and conditions may affect the applicability of the discussed equations.

dansmith170
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TL;DR
General Equation
Hi,

Is there a more general equation than the Compton equation that allows one to determine whether an electron will Compton scatter or inverse Compton scatter? If so, where can I find it (or what is it?)

Thanks.
 
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dansmith170 said:
Summary:: General Equation

Hi,

Is there a more general equation than the Compton equation that allows one to determine whether an electron will Compton scatter or inverse Compton scatter? If so, where can I find it (or what is it?)

Thanks.
You perhaps should have posted this under Special and General Relativity or Quantum Physics.
 
Thread moved. I figured high energy / particle / nuclear physics would be better.

As a quick answer, what you appear to be looking for is the probability that an electron will undergo Compton scattering. For that you need to start with the "cross section" for that process at whatever energy you're interested in.

Then you can compare it with the cross sections for other possible processes e.g. pair production, photoelectric effect, ...

If you tell us more about what you're trying to do, people can give more specific advice.
 
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jtbell said:
Thread moved. I figured high energy / particle / nuclear physics would be better.

As a quick answer, what you appear to be looking for is the probability that an electron will undergo Compton scattering. For that you need to start with the "cross section" for that process at whatever energy you're interested in.

Then you can compare it with the cross sections for other possible processes e.g. pair production, photoelectric effect, ...

If you tell us more about what you're trying to do, people can give more specific advice.
Thanks for moving the thread (I wasn't sure where exactly to put it). Big picture, I'm trying to come up with an equation that will allow me to figure out the number of electrons produced by the nonlinear Breit Wheeler process (and that process requires Inverse Compton Scattering as I understand it). And thanks for your response. Sounds the Klein-Nishina formula might be relevant.
 
dansmith170 said:
Thanks for moving the thread (I wasn't sure where exactly to put it). Big picture, I'm trying to come up with an equation that will allow me to figure out the number of electrons produced by the nonlinear Breit Wheeler process (and that process requires Inverse Compton Scattering as I understand it).
Inverse Compton scattering involves the scattering of low energy photons to high energies by ultrarelativistic electrons so that the photons gain and the electrons lose energy. That would most likely be a process in stellar atmospheres, but it could be induced in an electron (beam) accelerator colliding into a laser beam.
https://eud.gsfc.nasa.gov/Volker.Beckmann/school/download/Longair_Radiation3.pdf

The Breit–Wheeler process or Breit–Wheeler pair production is a physical process in which a positronelectron pair is created from the collision of two photons. It is the simplest mechanism by which pure light can be potentially transformed into matter. The process can take the form γ γ′ → e+ e where γ and γ′ are two light quanta. Ref: https://en.wikipedia.org/wiki/Breit–Wheeler_process from G. Breit and John A. Wheeler (15 December 1934). "Collision of Two Light Quanta". Physical Review. 46 (12): 1087–1091. Bibcode:1934PhRv...46.1087B. doi:10.1103/PhysRev.46.1087
https://journals.aps.org/pr/abstract/10.1103/PhysRev.46.1087


So, usually two photons would produce one electron-positron pair, unless the energies are very high to produce more than one pair. I'm not aware of this done in practice, although the Wikipedia article describes some experimental efforts.

Then - The multiphoton Breit–Wheeler process, also referred to as nonlinear Breit–Wheeler or strong field Breit–Wheeler in the literature, is the extension of the pure photon–photon Breit–Wheeler process when a high-energy probe photon decays into pairs propagating through an electromagnetic field (for example, a laser pulse).

However - Manufacturing such a source, a gamma-ray laser, is still a technological challenge. No S***!This has to do with - https://www.physicsforums.com/threads/breit-wheeler-matter-production.1010438/ ?
 
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Hi Astronuc, thanks for your reply and for the links. And yes, it's related to my earlier question about the mass production of electrons by means of Breit-Wheeler.
 

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