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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How to solve the Fukushima incident?

I am trying to find out if it is somehow possible to take all this nuclear material, put it in some type of gamma chamber or blast it with neutrons to change the uranium isotopes into something ...
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Can I excite an already unstable element for accelerated decay?

Say I had an unstable element ready to go through beta decay and I introduced it to high speed electrons: would this lessen the time needed for the product to go through beta decay?
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2 ways to generate electromagnetic wave

According to Maxwell's equations, accelerating charges emit electromagnetic radiation. According to Quantum physics, heating causes electromagnetic radiation too. These 2 radiations, are they ...
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Will the absorption of high energy gamma rays end up heating the absorping material?

By high energy I mean 100+ MeV gamma rays. I think that at this energy of photons, pair production is the dominating absorption process. So, as known, in pair production an electron and a positron ...
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100 views

Does halving the intensity of a gamma ray mean absorbing half its energy?

Say a 1 MeV gamma ray is shielded by 1 cm (halving thickness) of lead. Now, what does "havling the intensity" mean ? Like will the new gamma ray exit with energy of 0.5 MeV ? and by that we can say ...
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Is deep-space radiation greater in the Sun, or in the shadow of Earth?

http://space.stackexchange.com/questions/604/is-it-possible-to-get-pregnant-through-natural-means-in-space indicates cosmonauts are at risk of irradiation whilst in space. What little I know about ...
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214 views

Study of Black-body Radiation

Why did scientists study black body radiations from something as complicated as a hollow container rather than the radiation from something simple like a thin solid cylinder?
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Kirchhoff law of thermal radiation

Kirchhoff's law of thermal radiation states that for thermal equilibrium for a particular surface the monochromatic emissivity $\epsilon_{\lambda}$ equals the monochromatic absorptivity ...
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333 views

Is compton scattering only effective by x rayphotons and gamma ray photons

Can Compton scattering work with any other forms types of photons, and why was the the Compton Scattering experiment only done with x ray photons?
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233 views

How is the energy distributed in a proton-antiprotion annihilation?

I know the products of the annihilation, but I don't know how much energy each particle has or gets. For example I know that 1876 MeV is released for each annihilation. Now, this energy is distributed ...
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291 views

What is the halving thickness of diferent materials against high energy gamma rays?

By high energy gamma rays I mean 10+ MeV to 100 MeV. Is there a way to calculate it ? Also, at these high energies, do heavier elements like Lead for example still have the advantage over lighter ones ...
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235 views

Would matter-antimatter annihilation create a fireball or not?

There has been a long discussion between me and Anna V on if the products of the annihilation will really cause a fireball to form and we haven't settled it yet. Our point here is that gamma rays ...
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Would a matter-antimatter explosion cause fallout?

I know matter and antimatter annihilation release a lot of gamma rays which are considered ionizing radiation if I am not mistaken. But what if the explosion happened on the surface of the earth, ...
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213 views

Is there a way to increase photon energy by decreasing its wavelength?

Can I decrease a photon's wavelength by a medium or a vacuum? Are there other ways of decreasing the wavelength?
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212 views

What type of electromagnetic radiation strikes the Earth's surface the most?

If you can could you lists the types of light from the greatest amount to the least amount (Ex: Visible, Infrared, Violet).
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What is the shielding in nuclear reactors mainly against?

I have a little knowledge about ionizing radiation and I have been confused over why nuclear reactors need these massive shields. So, if I am not mistaken, Alpha and Beta radiation are not that ...
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155 views

Reflection, transmission, absorption…how to calculate them?

I was wondering whether there is an equation that enables me to calculate the reflection, transmission, absorption and polarization, when the electric field everywhere is given? Consider this: You ...
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141 views

Interaction of coherent X-rays with matter

If we could irradiate a metal or a plasma with a coherent beam of hard X-rays, would the main effect be an ordered oscillation of the electrons like with a classical EM wave, or "compton-style" ...
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154 views

Cherenkov radiation and K-40

I am thinking if it's possible to detect Cherenkov radiation in water caused by dissolved natural potassium (KOH) in it without using photo-multipliers. The main question is does 1 beta particle ...
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488 views

Alpha decay, why does it occur? [duplicate]

I was reading about alpha decay and why it happens. The strong force holds protons and neutrons together, but I don't get why does an atom emit helium nucleus when it has too many ...
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636 views

Why does positronium decay into 2 photons more often than into 3 photons?

I cannot find the answer to the above question. I know that para-positronium is created with a probability of $25\%$ and decays into 2 photons, while ortho-positronium is created with a probability ...
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Why were the fathers of quantum mechanics so sure radioactive decay was indeterministic?

The classic example of an indeterministic system is a radioactive isotope, e.g. the one that kills Schrödinger's cat. I get there are arguments against hidden variables in quantum mechanics, but how ...
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261 views

Trouble justifying calculation of force on a sphere due to radiation pressure

I know very little about electromagnetic waves and light in general so you are going to have to bear with me. I am attempting to calculate the force on a sphere in a plane wave of light where the ...
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114 views

Extreme heating by Sun on Earth- Can eggs be fried?

Will it be possible to fry eggs in Sahara desert by just keeping them under the sun? If so, then will the radiated eggs be any different? Or will we have to use the solar cooking concept to some ...
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Jupiter radiation belt: where >MeV particles comes from?

When I read some discussion about exploration of Jupiter moons, or possibility of life there, a common argument is high dose of radiation in Jupiter's radiation belt (several orders of magnitude ...
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The Observance of Electromagnetic Phenomena

As far as I've seen, E&M waves are sinusoidal. Our eyes observe these patterns and give us colors, but in a situation like such: Why do electrons emit radiation? There is still a wave, or at least ...
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Why do electrons emit radiation?

I know how you can emit light with an alternating current, running back and forth, creating an electric field in addition to the magnetic field. But why does an electron emit light when it gets ...
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What exactly is the composition of radiation in interplanetary space?

The articles I found on radiation in the solar system mostly dealt with solar wind, I wonder about other types. Is there a breakdown that tells me, withhin an order of magnitude, at least what ...
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185 views

What is Equilibrium Equivalent Concentration (EEC)?

Recently I am doing a research about radon measurement. During the process I met two concepts named Equilibrium Equivalent Concentration (EEC) and Potential Alpha Energy Concentration (PAEC), but ...
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What is a photopeak?

I'm currently studying for an exam, where I'm looking into decays and gamma radiation. I then have a diagram where there are stuff like "Compton scattering", "Single Escape Peaks", "Double Escape ...
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Do brick walls effectively protect against ionizing radiation from a nuclear explosion?

Of course it depends on the distance and the amount of radiation, so let's say its about 10,000 Rad. Now, can wall made of brick protect someone behind it from such radiation ?
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why can't you use your cellphone on an airplane? [closed]

why airplanes are banned with use of cellphones? What were the impacts while we answer an call or make an call ,what was the physical reason behind the ban of using cellphone inside airplanes ? I ...
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782 views

Radiation: Inverse square law

Gamma radiation follows the inverse square law, I understand this as "double the distance, quarter the intensity" So if you have a gamma source, at the source (distance = 0), the Intensity is $I_0$, ...
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41 views

Welding physics (black body and heat conductance)?

If I have two pieces of steel that I would like to weld with a laser (say $d$ in diameter). If I wanted to melt the two pieces to a depth of $d$ along the edge and then combine them together, how much ...
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2k views

How to calculate incident solar energy on earth in a given day with a spectral filter

The daily solar radiation irradiation is often quoted as being between $3.2 \text{ kW hours}/\text{m}^2$ and $7 \text{kW hours}/\text{m}^2$ per day . If you filter out a range of wavelengths, how can ...
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127 views

Optimal way to heat liquid from the sun?

I understand that one way to tell how much a liquid will be heated up by a remote heat source is by looking at its color. I assume clear and colorless heats up least, then white, other colors and last ...
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What's gonna happen if a nuclear bomb explodes nearby? [closed]

I live in the capital, 10 km from its center on the 9th floor, my windows facing the opposite direction will I still see a flash? Will I hear something? How loud will it be? How fast would I die? If I ...
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171 views

When (Exactly) Does Bremsstrahlung Radiation Occur?

Regarding the Bremsstrahlung Radiation emitted when a charged particle curves inside a uniform magnetic field; Is there a way of calculating the angle through which the charged particle will precess ...
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Why can Hiroshima be inhabited when Chernobyl cannot?

There was an atomic bomb dropped in Hiroshima, but today there are residents in Hiroshima. However, in Chernobyl, where there was a nuclear reactor meltdown, there are no residents living today (or ...
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859 views

When should angles be expressed in degrees vs. radians?

I am trying to calculate the albedo of a given latitude by following the methods of Brutsaert (1982), I have copied the formula below: 3.6 Shortwave and long-wave radiative fluxes Albedo ...
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218 views

How can we detect a black hole? [duplicate]

If black holes are phenomena of very high density (gravitational singularities) which don't emit radiation how can we detect them so far away from us where so much other radiation can hide the black ...
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What type of Radiation hits Europa

I was recently reading the Wikipedia Page for Europa as I am interested in terra-formation. In one of the sentences, it says that: The radiation level at the surface of Europa is equivalent to a ...
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Alpha particle and helium nucleus

The symbol for the alpha particle is α or $α^{2+}$, it can be written as $He^{2+}$. What I want to know is that, are they same? I mean alpha particle and helium nucleus are same or any subtle ...
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What is the difference between Radiation and Electromagnetic Radiation

Are the two equivalent or is Electromagnetic Radiation a subset of Radiation. I am further confused by the fact that electromagnetic radiation includes both ionizing and non ionizing types of ...
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Computing $\Delta m$ in $\beta^-$ decay

$\require{mhchem}$What is the energy $Q$ released when $\ce{^131_53I}$ decays and $\ce{^131_54 Xe}$ is formed? The atomic mass of $\ce{I}$ is $130.906118~u$ and the atomic mass of $\ce{Xe}$ is ...
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Why are alpha particles such a prominent form of radiation and not other types of nucleon arrangement?

It is said in many textbooks that alpha decay involves emitting alpha particles, which are very stable. Indeed, the binding energy (~28.3 MeV) is higher than for $Z$-neighboring stable isotopes. But ...
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Effective amplitude in Neutrinoless double beta decay

Can someone give me the value of the effective amplitude($A$) of $\bar{\nu_\mu}\rightarrow\nu_\mu$ oscillation of Neutrinoless double beta decay? The expression is like this: ...
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199 views

$\beta^+$ decay

We've been discussing radioactive decay at school, and I grasped everything except for $\beta +$ decay. When I googled radioactive decay, I immediately found out they dumbed down radioactive decay for ...
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Kinetic energy of alpha-particle in $^{212}$Po decay

Admittedly, Nuclear Physics is not my strength. I'm writing a simulation to model alpha-decay. So far, I have looked up the values of the kinetic energy of the alpha particles that are emitted in a ...
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Is a beta decay possible with out the emission of an electron in the process?

Is a beta decay possible with out the emission of an electron in the process ? Beta decay involves the formation of a proton and an electron from a neutron.