Lpzxaz
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I have a few questions for my physics assignment pleaseeee help. Online it says there are 2 different processes to create x rays which are X-ray fluorescence and bremsstrahlung and in another site it also says bremsstraughlung BUT instead of x-ray fluorescence it says characteristic radiation my question is, is X-ray fluorescence and characteristic radiation the same thing?

Also how is an x-ray image actually produced? The last step I have is that the lost energy from electrons are converted to x-ray photons but what are the steps after that?

Does x-ray spectrum come into this for medical x-rays? Like is it relevant I’m not sure what they do.

And I read somewhere 90% of the x rays produced in the x-day tube are due to bremsstrahlung so does that mean the other 10% is either x-day fluorescence or characteristic radiation?
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Stonebridge
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(Original post by Lpzxaz)
I have a few questions for my physics assignment pleaseeee help. Online it says there are 2 different processes to create x rays which are X-ray fluorescence and bremsstrahlung and in another site it also says bremsstraughlung BUT instead of x-ray fluorescence it says characteristic radiation my question is, is X-ray fluorescence and characteristic radiation the same thing?

Also how is an x-ray image actually produced? The last step I have is that the lost energy from electrons are converted to x-ray photons but what are the steps after that?

Does x-ray spectrum come into this for medical x-rays? Like is it relevant I’m not sure what they do.

And I read somewhere 90% of the x rays produced in the x-day tube are due to bremsstrahlung so does that mean the other 10% is either x-day fluorescence or characteristic radiation?
Fluorescence is a general term for radiation produced by excitation of electrons in an atom. Characteristic radiation on an X-Ray tube is a result of electron excitation in the target. So they are the same thing. In my experience, you would normally refer to this as characteristic radiation. I have never heard it described as fluorescence in this context, though it could be, of course.

I'm not sure I understand what you are asking in the 'what are the steps after that?' question.
If you are referring to this in the context of X-Ray imaging, then this is a result of the fact that bone and dense tissue absorb a lot more X-Rays than soft tissue does. X-Ray images are produced on a photographic plate (a negative image) and the image is darker where the X-Rays 'get through' and lighter where they are absorbed.

The X-Ray spectrum is not relevant to general X-Ray imaging in medicine. It is more about telling us things about the target material.

Yes. To the last part. And importantly, most of the energy of the electron beam in the tube is converted into heat in the target, which is normally cooled.
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Lpzxaz
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(Original post by Stonebridge)
Fluorescence is a general term for radiation produced by excitation of electrons in an atom. Characteristic radiation on an X-Ray tube is a result of electron excitation in the target. So they are the same thing. In my experience, you would normally refer to this as characteristic radiation. I have never heard it described as fluorescence in this context, though it could be, of course.

I'm not sure I understand what you are asking in the 'what are the steps after that?' question.
If you are referring to this in the context of X-Ray imaging, then this is a result of the fact that bone and dense tissue absorb a lot more X-Rays than soft tissue does. X-Ray images are produced on a photographic plate (a negative image) and the image is darker where the X-Rays 'get through' and lighter where they are absorbed.

The X-Ray spectrum is not relevant to general X-Ray imaging in medicine. It is more about telling us things about the target material.

Yes. To the last part. And importantly, most of the energy of the electron beam in the tube is converted into heat in the target, which is normally cooled.
Omg you are a legend thankuuu so much for answering in so much detail!!!

1. So x-ray fluorescence is the same as characteristic radiation? And bremsstrahlung is a different type

2. I’m confused as to how an image is made, like how exactly it gets onto the photographic plate, is a receptor involved? Is a computer involved? And what would I need to put

3. My assignment is medical physics so do you think I should include the x ray spectrum it was in the PowerPoint my tutor sent out but I’m not sure if it’s relevant

4. When you said yes do you mean x rays in hospitals are made up of 90% Bremsstrahlung and 10% is characteristic radiation? I wasn’t sure if it some x rays used JUST one of these and some x rays would use one of the other? So an x ray uses both types?
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Stonebridge
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(Original post by Lpzxaz)
Omg you are a legend thankuuu so much for answering in so much detail!!!

1. So x-ray fluorescence is the same as characteristic radiation? And bremsstrahlung is a different type

2. I’m confused as to how an image is made, like how exactly it gets onto the photographic plate, is a receptor involved? Is a computer involved? And what would I need to put

3. My assignment is medical physics so do you think I should include the x ray spectrum it was in the PowerPoint my tutor sent out but I’m not sure if it’s relevant

4. When you said yes do you mean x rays in hospitals are made up of 90% Bremsstrahlung and 10% is characteristic radiation? I wasn’t sure if it some x rays used JUST one of these and some x rays would use one of the other? So an x ray uses both types?
1. Yes. Bremsstrahlung means 'breaking' or deceleration radiation. 90% of the X-Rays produced in the tube are the result of the sudden deceleration of the electron beam as it strikes the target. The 'characteristic' radiation, which is also often referred to as the X-Ray 'line spectrum' is the result of electrons deep in the target material atoms being ejected by the collisions from the electrons in the beam. This leaves behind gaps in the energy levels in the target atoms. Electrons then 'fall' back into the atoms in the target (into the gaps in the target atom electron levels) and emit radiation as they so that. As the electrons in the target atoms are in specific energy levels, the radiation emitted by this mechanism has specific 'characteristic' wavelengths.

2. As far as I'm aware, the X-Rays fall on a photosensitive material and produce a negative image in the same way an old fashioned film camera does.
A Google search on X-Ray detector will tell you all you need to know on this. https://en.wikipedia.org/wiki/X-ray_detector

3. 4. As far as the medical physics is concerned, it is irrelevant which type of X-Ray is used. Depending on the tube producing them, the X-Rays will be a mixture. There is no physical difference between one or other of the X-Rays, brehmstrahlung or characteristic. An X-Ray is an X-Ray from wherever it comes or however it was produced.
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