The x-ray tag has no wiki summary.
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Have we observed another supernova explosion since SN 2008D?
I read the wikipedia article about SN 2008D which says:
"Now that it is known what X-ray pattern to look for, the next generation of X-ray satellites is expected to find hundreds of supernovae every ...
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How are X-rays focused? Specifically in XRD. Well do they even focus X-rays in XRD?
I read in a government website that reflecting an x-ray from a parabolic mirror followed by a reflection from a hyperbolic mirror results in focusing the x-ray, but this was for astronomical purposes. ...
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243 views
Is the index of refraction dependent on the wavelength of light?
I just read in some class notes for a crystallography class that there are no refractive lenses for X-rays because the index of refraction of most materials is close to 1. Is the index of refraction ...
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Reflectance and Absorption properties of X-rays
Are there any materials that are mostly "transparent" to x-rays? Such as glass would be to the visible spectrum?
What about materials or surfaces that reflect x-rays? Does most metal reflect x-rays?
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Finding out the wavelength of Xray [closed]
A sheet of aluminum 1 mm thick reduces the intensity of a monochromatic x ray beam to 23.9% of at original value. what is the wave length of xray.
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1answer
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Why, in EXAFS spectrum, does the absorption coefficient monotonically decrease with increasing photon energy?
In atomic physics, it is common knowledge that following the absorption edge, where the photon energy equals the binding energy of a core electron, a monotonic decrease in the absorption coefficient ...
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2answers
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Why possibility for X-ray to excite inner electrons higher than outer electrons?
It seems X-ray absorption spectroscopy is usually ascribed to the interation between photons and inner electrons. Does it mean inner electrons are much preferred by X-ray photons to outer electrons? ...
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1answer
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1MeV ray hits a band gap of 2eV : trying to understand X-rays
I am trying to understand why radio waves pass though the human body, light does not, but X-rays still pass.
In my mind I imagine that radio waves don't supply enough energy and don't excite any ...
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3answers
374 views
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. ...
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1answer
126 views
Why are there photographs of nuclear tests?
I was looking at old photographs of the nuclear tests on the bikini atoll. It dawned on me that you don't want to run film through airport x-rays, as it exposes the film. I've been told that a ...
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104 views
Cross section of photoelectric absorption vs Thomson scattering cross section
I am interested in more less the same issue as asked here but my question is:
Why for the low X-rays the photoelectric absorption is dominant over Thomson/Compton scattering? I am considering the ...
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2answers
164 views
Compton scattering multiple wavelengths?
The formula given for compton scattering shows that when x-ray of one specific wavelength hits carbon or some materials, emitted x-ray will be of one new specific wavelength.
However, according to ...
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1answer
613 views
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 ...
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2answers
171 views
Why do we stop using optics for photons above a certain energy?
I'm reading about how the soon-to-be-launched NuSTAR is on the cutting edge of focusing x-rays, which captures 5 to 80 keV radiation by focusing them with optics that have a 10.15 meter focal length ...
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2answers
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What is 2 $\theta$ in X-ray powder diffraction (XRD)?
Why are we taking 2$\theta$ instead of $\theta$ in X-ray powder diffraction (XRD). I have found the forum post 2 theta in X-ray Powder Diffraction (XRD), but there is no answer. What is the ...
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2answers
187 views
Can x-ray radiation be compared to background radiation?
I've been trying to learn about the possible effects of x-ray radiation from dental x-rays and most of the resources I come across compare the exposure to that of natural background radiation.
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2answers
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What is the process called that produces characteristic X-rays?
X-rays mostly consist of bremsstrahlung and characteristic X-rays. What is the process called that gives rise to the latter (but not the former)?
I'm trying to write a sentence like "X-rays are ...
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1answer
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Where does the photon's energy come from in X-ray bremsstrahlung?
In an X-ray tube, bremsstrahlung is generated by accelerating electrons toward a target metal. As a photon is emitted, something loses energy. I suppose that the target metal remains fixed and is ...
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2answers
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How do metallic objects interfere with X-Rays?
During my visit to the doctors', I recollect having seen the sign which says
Please remove all metallic objects from the body before the commencement of the X-Ray
How do metallic objects ...
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1answer
243 views
Absorption / Control / Reduction of EMF radiation using passive antennae & matched load
Wanted to understand the physics behind usage of passive antennae and matched load combination, to absorb, control and reduce the Electromagnetic-Field (s.a. due to microwave radiation from cellular ...
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1answer
673 views
Where are the ice rings in X-ray crystallography located?
I threw this image of one of my protein crystal's diffraction pattern (not the greatest) on a poster, and was wondering where (what reciprocal dimension) the ice rings are located as it might be a ...
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1answer
281 views
What happens if you x-ray an x-ray?
The title largely sums up my question, what does happen if you either x-ray an x-ray, or point two x-ray generators at each other?
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Light vs. X-ray interactions with Phosphor
Looking for some information on how light and xrays interact with phosphorous, or what might cause the following:
Scenario
A focus beam of light is directed at a phosphor plate at the same time as ...
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6answers
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How can a black hole emit X-rays?
Considering that a black hole's gravity prevents light from escaping, how can a black hole emit X-rays? Visible light and X-rays are both electromagnetic radiation, shouldn't the black hole's gravity ...
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2answers
183 views
Can one see radioactive substances with an X-ray detector?
I was wondering the other day an X-ray detector (like the ones used at airports) can detect gamma-rays lets say from a sample of uranium. I know its all electro-magnetic waves but I'm really unsure ...
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2answers
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How does fluoroscopy (x-ray) imaging work in practice?
I know the basics, that by measuring how much x-ray signal reaches each 'pixel' on the receiver we can measure how much has been absorbed. But this gives only a single channel of information, e.g a ...
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1answer
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Do XAFS excitations and subsequent relaxations lead to vibrationally hot molecules?
I'm in the process of trying to understand X-Ray Absorption Fine Structure (XAFS) spectroscopy, but I think this question is more fundamental than merely as it pertains to XAFS. I think I don't ...
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3answers
123 views
Can a multipass x-ray absorption cell be constructed?
I've been trying to understand the various concepts behind x-ray optics compared to standard visible/IR optics like mirrors and such. However, the x-ray mirrors I've been finding typically have ...
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1answer
154 views
Proton therapy in cancer treatment
Why are protons used in cancer therapy ? Is there any advantages compared to classics X-rays treatment or electron treatment ?
