Questions tagged [radiation]
Radiation is a process in which energetic particles or energetic waves travel through a medium or space. The particles or waves radiate (i.e., travel outward in all directions) from a source.
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Radiation through optical windows
Edit: I have tried answering this a different way since posting this, see my newer answer below.
Problem I'm interested in solving: How much radiative heat load is entering the system through optical ...
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Radioactive Decay Chain for the special case of equal decay constants (parent-daughter)
I have been trying to obtain an analytic solution for a daughter radionuclide's activity (or just the number of daughter atoms), as a function of $t\geq0$, resulting from the decay of a parent ...
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Why doesn’t Bremsstrahlung occur in simple flows of electrons?
From what I have read, bremsstrahlung is caused by electrons loosing kinetic energy when being decelerated by another charged particle. The lost energy being converted into radiation.
So why isn’t ...
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Total flux is bigger than radiation flux, error?
The topic of this question is the collection of radiation from the sun. (renewable energy course) The total radiation flux is $$I_\text{total} = I_\text{direct}+I_\text{diffracted}+I_\text{reflected} ....
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Neutron Beta Decay Spectrum
Beta decay is generally displayed as below with a fairly significant intensity of electrons emitted with KE ~ 0. In this case, all the energy of the decay is given to the neutrino and the momentum is ...
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Is electron capture the exchange of a virtual $W$-boson?
Betaplus: an upquark emits a $W^+$-boson which turns it into a downquark and then decays into a positron and electron neutrino.
Electron capture: an upquark emits a $W^+$-boson which is absorbed by a ...
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Effective aperture as a function of Azimuth and Elevation Angle
Wikipedia says
The effective aperture of an antenna is given by $$A_{\mathrm{e}}(\theta, \phi)=\eta A \cos \theta \cos \phi ,$$
where, $(\theta, \phi)$ are the azimuth and elevation angles relative to ...
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Paradox in the observation of ripple
What I am going to speak about may not be a paradox but i see a contradiction here so I used used the word "paradox". To begin with, let there be 2 charges A and B which are stationary with ...
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What is "point of interest" and why isn't there a Zref for determining electron beam quality with TRS 398?
What is "point of interest" and why isn't there a Zref for determining electron beam quality with TRS 398?
((To what depth do you put the ion chamber when you do high energetic electron ...
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What are the benefits/weaknesses of different diffusion models in radiation transport?
Can anyone summarize or point me toward references for why someone would choose one diffusion model over another, particularly in relation to radiation transport during a nuclear blast? The diffusion ...
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Heat transfer and Stefan-Boltzmann law and black body radiation [closed]
can there exist a black body (theoretically) which has a cavity in it I don't mean Fery's black body I am referring to a black body which is made of a MATERIAL which has the property to emit and ...
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Can a body be in thermal equilibrium at a different temperature from surroundings?
As per my knowledge bodies attain constant temperature (thermal equilibrium with surroundings) when they absorb and emit energy at equal rates.
Let us say temperature of surroundings is T1.
We have a ...
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Does the neutrino take on different masses/energy/mometum in beta decay?
I am currently learning about quantum mechanics in my 12th grade Physics course and we're currently covering nuclear energy levels.
I understand that alpha and gamma decay is discrete, as there is ...
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Back scatter imaging
backscattering is already part of Compton scattering for X-rays.
Compton scattering is directly proportional to the density of the material i.e. as the density increases as the Compton scattering ...
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Understanding the decay of Na-22
When looking at data for Na-22 decay (e.g. here: https://www.nndc.bnl.gov/nudat3/DecayRadiationServlet?nuc=22Na&unc=NDS ) it shows that for every 100 decays, there should be:
99.94 gammas with ...
