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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Is there a way to decrease the rate of nuclear Beta decay?
In that question and its answers it was mentioned that you could trigger radioactive decay by bombarding atoms with gamma rays of the right energy level (there may be other solutions I do not know ...
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2answers
317 views
Nuclear decay rate affected by sun and quantum randomness
If nuclear decay rate were affected by sun,
then emission probabilities would be subject to sun state and its influence,
so quantum randomness would depend on it,
Would it still be truly random?
One ...
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1answer
607 views
Why doesn't orbital electron fall into the nucleus of Rb85, but falls into the nucleus of Rb83?
Rb83 is unstable and decays to Kr-83. Mode of the decay is electron capture. Rb85 is stable.
The nuclei Rb83 and Rb85 have the same charge. Rb85 is heavier than Rb85, but gravitation is too weak to ...
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779 views
Is there any thing other than time that “triggers” a radioactive atom to decay?
Say you have a vial of tritium and monitor their atomic decay with a geiger counter. How does an atom "know" when it's time to decay? It seems odd that all the tritium atoms are identical except with ...
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769 views
Decay of massless particles
We don't normally consider the possibility that massless particles could undergo radioactive decay. There are elementary arguments that make it sound implausible. (A bunch of the following is ...
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5k views
What exactly is the difference between radiation and convection?
Okay, so everywhere I've read, I hear the main difference is the requirement of a medium. But for example, if you take the case of heat 'radiating' from a red-hot iron, isn't that actually convection ...
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2answers
210 views
Antimatter bomb
I stumbled upon this wikipedia article on antimatter weaponry.
Being greatly appalled by the sad fact that large sums of money are being wasted on this, I could not stop myself from thinking for a ...
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2answers
703 views
Tunneling of alpha particles
Consider this explanation of the alpha decay: It says
The Coulomb barrier faced by an alpha
particle with this energy is about 26
MeV, so by classical physics it cannot
escape at all. ...
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1answer
104 views
Specific electron energy gap values $E_{i+1}-E_i$ vs. photons with arbitrary energy $\hbar \omega$
The energy levels of electrons in an atom are quantized $E_i$. A photon of a specific momentum $\vec p$ and energy $$\omega=(E_{i+1}-E_i)/\hbar$$ hits an atom and gets absorbed. Okay now say the ...
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764 views
Why some nuclei with “magic” numbers of neutrons have a half-life less than their neighbor isotopes?
It's easy to find the "magic" numbers of neutrons on the diagrams of alpha-decay energy: 82, 126, 152, 162. Such "magic" nuclei should be more stable than their neighbors.
But why some nuclei ...
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3answers
364 views
Cosmic ray hazards
The Pierre Auger Observatory site mentions the detection of a 3E20 eV (48 J) cosmic ray whose energy, well above the GZK cutoff, was based on an analysis of its atmospheric shower. This was equivalent ...
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177 views
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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557 views
What temperature can you attain with a solar furnace?
A solar furnace is a device that concentrates the sun's light on a small point to heat it up to high temperature. One can imagine that in the limit of being completely surrounded by mirrors, your ...
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2answers
217 views
Where does the excess energy emitted by a microwave go?
If there is nothing in the microwave, where does the excess radiation go?
Why doesn't the radiation accumulate and blow it up?
Should I cook two pieces of Canadian Bacon twice as long as I cook one?
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2answers
216 views
Reconstruction of information stored in an evaporating black hole from the emission spectrum?
For simple setups, where the radiation field deviates not too far from thermodynamic equilibrium (< 10 %), corrections to the Planckian thermal emission spectrum can be calculated (and measured) ...
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2answers
1k views
Why are alpha particles made of 2 protons and neutrons?
When experiencing alpha decay, atoms shed alpha particles made of 2 protons and 2 neutrons. Why can't we have other types of particles made of more or less protons?
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596 views
Can you speed up radioactive decay of plutonium?
We all know the issue of deep geological repositories for fuel rods. Is there a way to speed up the rod's decay to render them harmless in less than 10 years?
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511 views
What other shielding material than lead is effective against gamma rays?
As the question in the title states I am wondering what material can be effectively used to shield gamma rays apart from lead? I believe concrete is often used, but it is nowhere near as effective as ...
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3answers
442 views
Are these radioactive particle matter and air emmissions dangerous, 2000KM from Fukushima?
I have 2 questions, as a expat and new parent residing in Shanghai (2000km from Fukushima) where we are now experiencing radioactive fallout from the Fukushima Nuclear Plant (Japan), we can not get ...
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1answer
137 views
Does an object's color change its rate of cooling?
The motivation for this question comes directly from this thread. The proposition is that the color of something changes how fast it cools (note: specifically the rate of cooling, not taking into ...
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1answer
53 views
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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2answers
229 views
Is it possible to speed up radioactive decay rates? [duplicate]
Possible Duplicate:
Do some half-lives change over time?
Would it be possible to considerably speed up the decay rate of an isotope?
Considerably meaning more then a 1 or 2% increase in ...
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2answers
128 views
How is a cathode ray tube different from beta minus radiation?
In beta minus the result is one neutron in the nucleus changing to a proton, plus an electron and an anti-neutrino being sent off.
The antineutrino is indifferent to our health. So I guess what ...
