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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What astrophysical or artificial light sources provide the highest usable irradiance at the Solar Gravitational Lens focal line (∼550–1000 AU)?
The Solar Gravitational Lens (SGL) concentrates light from distant sources into a narrow diffraction pattern along its focal line, starting at ~550 AU. The central PSF contains extremely high ...
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Alpha particles and the very unwavelike behavior [duplicate]
We're still trying to figure out why alpha particles move in straight lines instead of a wave-like probability moving in all directions. I am wondering if anyone has put any thought into maybe they ...
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Is there a periodic table showing the radioactivity of elements in their natural isotoic ratios?
In something like decays per second because a stable elements doesn't really have a half life
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Why a particle (specifically lepton) decays?
This is a sequel of my question. For particles with structure, it wouldn’t be strange for them to decay due to unstable structure and various reasons. But for leptons, such as the muon, it's almost ...
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Will gases contained inside a box eventually reach zero temperature?
Suppose I have some amount of gas inside an isolated box.
As the gas molecules continue colliding with box wall and each other, there will be a loss of energy due to these collisions.
So, will over ...
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Is there a limit where the inverse square law does not apply?
Struggling to wrap my head around making estimates of neutron dose rates. I have an AmBe neutron source, surrounded by a neutron shield with a complex shape (due to engineering considerations). It is (...
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Can Ultraviolet Light Penetrate Fiberglass?
I was installing a fiberglass camper shell on my pickup on a sunny day. When I climbed in the back to install the bolts and secure the shell to the truck, of course it was shaded from the sun. After a ...
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Which Dosimetry Approach is Correct?
I have been studying gamma and X-ray irradiation for sterilisation purposes. Dosimetry plays a crucial role in this concept. The unit for dose it in Gray (Gy) which is,
$$\text{Dose (Gy)} = \dfrac{\...
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How to reconcile photons and different aspects of electromagnetic fields? [closed]
I am learning about fields and EM waves, and there is something I find trouble reconciling. I am told of the field theory of electromagnetics, but then I also read fields are simply made of photons? ...
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Intuitive explanation for the combinatorial factor present in $d\Gamma$ (diff. decay rate)
The formula for the differential decay rate of an unstable particle that decays into $n$ particles (as given in Wikipedia and other sources) is:
$$d\Gamma_n=\frac{S|\mathcal{M}|^2}{2M} d\Phi_n(P;p_1,...
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Deriving the power density of Johnson's noise (as in Feynman's Lecture I.41)
This is a question related to sections 41.1 41.2 and 41.3 of the Feynman Lectures on Physics (vol I). Below, I will summarize the content of section 41.1 and 41.2 and then report what is unclear to me ...
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What is my geiger counter picking up from this neon discharge lamp?
This is just a mini tesla coil exciting an Eisco neon discharge lamp. The detector is a MightyOhm geiger ++ which detects beta and gamma radiation. I'm recording 30-60 CPM just with background ...
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Weird behavior in spark gap alpha particle detector
I recently happened upon some americium. I wanted to measure its alpha emissions, so I built a spark alpha detector which consisted of some thin copper wire stretched about five millimeters above a ...
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What could be a mechanism that affects decay of isotopes and other processes subject to time dilation? [closed]
In relativity objects can age at different rates depending on their experience of spacetime. This seemingly occurs equally for four different kinds of processes
decay of isotopes,
the lifetime of ...
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Is exposure to lead better than exposure to radiation? [closed]
I'm not sure if this would be more befitting of Bio.SE but I feel members of Phys.SE would be better placed to answer this as it may or may not be answered in research for safety in environments which ...
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