Use this tag for question related to X-rays which are a form of high energy electromagnetic radiation having wavelength ranging from 0.1 to 10 nanometres. Also referred to as Röntgen radiation after the scientist who discovered it. X-rays have a range of application including medical CT, airport security, astronomy, crystallography, etc. Different applications use different parts of the X-ray spectrum.
Questions tagged [x-rays]
364 questions
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Direction of X-rays from x-ray tube
Typically anode of X-ray tube is at angle of ~45 degrees. Many images show that emitted X-rays are mostly perpendicular to electron direction.
Is that correct?
I had an impression that x-rays will be generated isotropically and only partially…
BarsMonster
- 2,371
4
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X-ray imaging of coconut
I'm doing the X-ray imaging of a coconut with soft X-rays. But the images have no contrast between the rice and water inside the coconut. How can I adjust the parameters to see this contrast inside the coconut? Horizontal and vertical projection…
Lan Anh Pham
- 51
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Medical X-rays energy spectrum
When you have your X-Ray tube, and want to make X-Ray for your X-Ray scanner or whatever. Then you get electrons from the cathode, which hit the anode, and from that produce a spectrum of X-Rays due to Bremsstrahlung, and characteristic lines from…
Denver Dang
- 2,517
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Differences between X-Ray and Electron Diffraction
I would want to know what the differences between these two techniques in cristalography. I research on internet, but it is not clear to me what each one does.
When it's better to use one and not the other?
What things that only one of them can…
Pierre
- 131
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Attenuation of X-Ray Radiation
I have a question regarding the attenuation of x-ray radiation in a Medium. Let us Assume we have a phantom like this:
The darker the gray, the higher is the attenuation of x-ray radiation of the material in that region.
Now let us further assume…
PKlumpp
- 193
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Why does the Bremsstrahlung radiation intensity decrease linearly with photon energy?
Why does the spectrum for Bremsstrahlung radiation decrease linearly with photon energy after a certain point (50 keV in the plot)?
probablysid
- 97
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Why does x-ray films look better when illuminated with light?
Today I got an x ray of myself and it seems that it was much easier to distinguish between bones in the x ray when the films were illuminated with light from either side from either side. What is the physics explanation of why this phenomena…
tryst with freedom
- 7,940
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Why is it necessary to dissipate the heat of the anode in an X-ray tube?
I understand that in an X-ray tube electrons collide with the anode which then deflects them out of the window producing X-rays and that this anode is rotated to dissipate heat. But why is it necessary? I imagine the cathode filament will get far…
tom894
- 187
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Upper bound on frequency of photons generated by an x-ray tube
It is my understanding that X-rays can be generated by placing an anode and cathode in a vacuum tube, then creating a high voltage differential between them causing the electrons to be accelerated between the anode and cathode. The energy gained by…
Mathew
- 1,123
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What's the issue with inventing a cold cathode X-ray tube?
My dad requires many CT scans, and we're asking this out of curiosity. We're not promoting or affiliated the company.
Can someone please explain the para. below like I'm 5, in Simple English? The company's website uses even more abstruse parlance,…
user284009
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vote
1 answer
X-RAY production from Coolidge Tube
In a Coolidge tube, electrons are ejected with a Kinetic Energy. They strike the metal target and during collisions lose some part of the KE which gets emitted in the from of electromagnetic waves(photons of varying energy). Not that it matters, but…
HappyFeet Me
- 13
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How would you reconstruct a CT image from two sinograms?
Say you perform a dual-energy x-ray CT scan using a high and low energy spectrum on three different materials. Since you're using two different energy levels, there will be two sinograms. But how would you reconstruct the main image of some…
Oliver G
- 73
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Secondary electrons in X rays excites more than ionize. Why?
In secondary electrons, it is said that electrons excite 8 times more than ionize. Only 3 eV is needed to excite and 10eV to ionize. Why is it so, as binding energy of inner shell can reach up to 70KeV. Thank you.
user190776
- 11
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What is invisible to x-rays?
Is there any physical matter which won't appear on x-ray i.e. invisible matter?
I think I learnt at university that all phsyical matter appears on x-ray and there is no matter that can be invisible. Is this true? For instance, does dark matter and…
Niklas Rosencrantz
- 1,043
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Does the total conversion of electron energy into X-ray imply the electron comes at halt in the short wavelength limit of X-ray radiation?
Suppose an electron hits a metal target after being accelerated in an X-ray tube. The production of the continuous X-ray is explained by stating that the electron decelerates continuously. In that process, it loses kinetic energy which is converted…
Samapan Bhadury
- 938