Soft X-Rays: Causes & Energy Rates

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Discussion Overview

The discussion revolves around the causes and energy rates of soft X-rays, exploring the mechanisms of their generation, particularly in relation to accelerated electrons and their interactions with atoms. Participants delve into concepts such as Bremsstrahlung radiation, the role of synchrotrons, and the relationship between electron energy and emitted photon characteristics.

Discussion Character

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

Main Points Raised

  • One participant questions whether the deceleration of an accelerated electron due to electric field interactions and scattering near the nucleus contributes to soft X-ray production.
  • Another participant explains that soft X-rays have less energy than hard X-rays and describes the traditional method of generating X-rays through electron acceleration and collision with a metal film.
  • Some participants mention Bremsstrahlung radiation as a relevant concept and provide a link for further reading.
  • There is a discussion about the role of synchrotrons and undulators in generating soft X-rays, with references to the magnetic fields involved.
  • One participant raises a question about the relationship between the energy of emitted photons and the deceleration of electrons, seeking clarification on governing factors.
  • Another participant notes that the maximum energy of produced X-ray photons is limited by the energy of the incident electrons, which is related to the voltage of the X-ray tube.
  • There is a mention of a cascade effect in bremsstrahlung radiation, where interactions with matter lead to additional photon generation, albeit with lower energies.
  • Several participants express frustration about communication and clarity in the discussion, indicating a need for clearer questions and responses.

Areas of Agreement / Disagreement

Participants express various viewpoints on the mechanisms of soft X-ray generation, with some agreeing on the relevance of Bremsstrahlung radiation while others seek clarification on specific aspects. The discussion remains unresolved with multiple competing views and questions still open.

Contextual Notes

Some statements rely on assumptions about the behavior of electrons and the conditions under which X-rays are generated. The discussion includes references to external resources for further exploration of the topic.

Entanglement
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what is the reason of soft x-rays, Is it because when a accelerated electron approaches an atom the electrons' electric field repel the incoming electron causing deceleration and also i scattering could be a reason when the electron approaches the nucleus, is that correct?
what is the relation of the number and energy of photons emitted to the rate of its deceleration, how can it be calculated? Big :smile: to PF, and thanks in advance!
 
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"Soft x-rays" have less energy than "hard x-rays". The traditional method for making x-rays was to accelerate electrons through a fixed potential - call it V - so that every electron has the same energy; about eV in this case.

Then collide the electrons with a thin metal film. If the electron energy is sufficient, then the "characteristic x-rays" for that metal will be emitted.

"Hard" x-rays are more penetrating.

See https://en.wikipedia.org/wiki/X-ray_generator
 
UltrafastPED said:
"Soft x-rays" have less energy than "hard x-rays". The traditional method for making x-rays was to accelerate electrons through a fixed potential - call it V - so that every electron has the same energy; about eV in this case.
Then collide the electrons with a thin metal film. If the electron energy is sufficient, then the "characteristic x-rays" for that metal will be emitted.
"Hard" x-rays are more penetrating.
See [PLAIN]https://en.wikipedia.org/wiki/X-ray_generatorsf[/PLAIN]
 
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UltrafastPED said:
"Soft x-rays" have less energy than "hard x-rays". The traditional method for making x-rays was to accelerate electrons through a fixed potential - call it V - so that every electron has the same energy; about eV in this case.
Then collide the electrons with a thin metal film. If the electron energy is sufficient, then the "characteristic x-rays" for that metal will be emitted.
"Hard" x-rays are more penetrating.
See https://en.wikipedia.org/wiki/X-ray_generator
Thanks a lot for your answer, but I don't think you understood my question correctly :smile:
 
ElmorshedyDr said:
Thanks a lot for your answer, but I don't think you understood my question correctly :smile:


Maybe can work you some question so it clearer be.
 
Yeah, clearer question would help.

Soft x-rays are typically generated at synchrotrons and wiggling the electron beam using an undulator.
 
I mean I know that when an electron falls from a higher level it emits a photon of energy hv,
What is the equivalence of that for decelerating electrons, what governs the number of photons and the energy of each photon??
 
The undulator produces a magnetic field that acts on the electron beam (http://en.wikipedia.org/wiki/Undulator).

A magnetic field has a potential energy similar to a (quantum) harmonic oscillator along one axis (Introductory Quantum Mechanics, Liboff 4th editon).

I'm guessing the transitions are harmonic oscillator type transitions, with higher energy and lower energy states available.
 
  • #10
ElmorshedyDr said:
..... what governs the number of photons and the energy of each photon??

The maximum energy of the produced X-ray photon is limited by the energy of the incident electron, which is equal to the voltage on the tube times the electron charge, so an 80 kV tube cannot create X-rays with an energy greater than 80 keV

Dave
 
  • #11
For braking radiation, conservation of energy tells us that the total energy released as photons cannot exceed the total energy of the initial source.

An x-ray passing through matter will have multiple interactions, all electromagnetic, knocking off electrons as it goes. These electrons will in turn generate additional photons - a chain reaction - but with ever lower energies in the photons, and in the electrons.

This cascade is called bremsstrahlung or braking radiation.

For some calculations see http://www.astro.utu.fi/~cflynn/astroII/l3.html
and http://whs.wsd.wednet.edu/faculty/b...onphysics/lecturenotes/chapter7/chapter7.html
 
  • #12
its so much fun being ignored :frown:
 
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  • #13
davenn said:
its so much fun being ignored :frown:

It's my favorite activity! :-p
 
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  • #14
Thanks guys I got it. :smile:
 
  • #15
davenn said:
its so much fun being ignored :frown:
What do you mean?
 
  • #16
ElmorshedyDr said:
What do you mean?

That was for me, so you can just ignore it. :smile:
 

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