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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Without a reactor vessel breach, how does radiation build-up in containment buildings of troubled nuclear reactors?
It seems that at Three Mile Island and in Fukushima, there was a build-up of radioactive gasses, and other gasses like hydrogen in the containment buildings.
Wikipedia says: The containment ...
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2answers
161 views
Is there a reason for photodynamic therapy to not cause cancer if mobile phones might?
I don't want to open a debate about whether cell phones can cause cancer,
I read the thread: Could cell-phone radiation cause cancer?
For the sake of this question let's assume there's a chance for ...
5
votes
2answers
347 views
Sunflowers and radioactivity
I read yesterday that sunflowers were used and to cleanup radioactivity at Chernobyl and the Atomic Bomb sites in Japan and may be used as part of a campaign to clean up the Fukushima area.
But my ...
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0answers
43 views
radioactive decay in molecular constituents [duplicate]
Possible Duplicate:
What happens to chemical compunds that include radioactive nuclei, when those decay?
Suppose a radioactive atom, which is incorporated in a molecule, decays? What ...
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3answers
770 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 ...
9
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1answer
289 views
Laptops in space
I was reading an article regarding the Shuttle's GPCs and how they stack up against commercially-made hardware on http://www.nasa.gov/mission_pages/shuttle/flyout/flyfeature_shuttlecomputers.html and ...
5
votes
2answers
513 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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vote
3answers
644 views
Are dangerous rays emitted during Solar Eclipse?
It is said one should avoid staring at Sun as it can damage the eyes, but it is also said that one should not come out in sun during eclipse as it emits dangerous rays. Is that true? If yes, why?
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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 ...
4
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1answer
274 views
Transverse current equivalence in Coulomb gauge
I have a question concerning transverse (solenoidal) current in the Coulomb gauge. This current is the one that enables the radiation, since we have a wave equation for the vector potential:
...
5
votes
2answers
704 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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vote
1answer
422 views
Wein's fifth power Law and Stephan Boltzmann's fourth power laws of emissive power
Wien's fifth power law says that emissive
power is proportional to
temperature to the fifth power.
But the Stefan–Boltzmann
law says emissive power is
proportional to temperature to the fourth power.
...
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2answers
266 views
Do and can phone signals come inside AC car which is glass-packed
Can phone signals penetrate glass, so can I expect phone signals to come if I am sitting inside a closed AC car.
Thanks,
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3answers
240 views
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 ...
2
votes
2answers
217 views
What is the risk from radiation on imported food from Japan
I'm currently resident in Hong Kong a country which appars to import heavily from Japan.
Last saturday 7th May I went to a restaurant:
http://www.openrice.com/english/restaurant/sr2.htm?shopid=39760
...
4
votes
1answer
184 views
The most stable metal for radioactive environment
Could you suggest which metal/alloy shows the least activation & better long-term stability for space (LEO, inside Van allen belts, deep space) applications?
Or stability of construction ...
5
votes
1answer
146 views
Oort Cloud Detection
The hypothetical Oort cloud is an explaination for long period comets. It presumably is made up of icy bodies orbiting up to 50,000 AU from the Sun. If so, shouldn't the Spitzer IR telescope have ...
3
votes
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 ...
2
votes
1answer
98 views
Solar Cycle UV Variation
The average energy we receive from the Sun is 1,366 w/m^2, and this only varies by 0.1% from the activity peak to trough of its 11 year cycle. About 9% of the energy comes from wavelengths less than ...
3
votes
2answers
580 views
What is the required thickness of concrete needed to entomb a leaking reactors emissions?
What is the minimum thickness of an aggregate concrete membrane to prevent radioactive particles from escaping a broken reactor?
I am interested in calculating the amount of concrete required to ...
1
vote
2answers
230 views
$\alpha$ and $\beta$-decay, why don't they neutralize each other?
$\alpha$ radiation consist of positive charged helium nuclei, $\beta$ radiation of negative charged electrons. So why don't the $\alpha$ particles take those electrons to get neutral?
3
votes
3answers
217 views
Ratio of radiation sources in the uranium cycle
Sorry, I know y'all are probably getting a lot of questions re: Fukushima, but I had a very specific one and no-one has been able to answer it.
I am specialised in medical radiation, and have been ...
7
votes
2answers
517 views
Is it Possible to Determine Radiation Levels Using Satelites?
Given recent events in Japan, this got me wondering. Is it possible to determine radiation levels reliably not having Geiger counters near the possible radiation contaminated zone? According to ...
4
votes
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 ...
6
votes
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 ...
9
votes
6answers
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 ...
5
votes
1answer
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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vote
2answers
217 views
Creation of the Electromagnetic Spectrum [closed]
After seeing this image:
http://mynasadata.larc.nasa.gov/images/EM_Spectrum3-new.jpg
And reading this:
"The long wavelength limit is the size of the universe itself, while it is thought that the ...
10
votes
3answers
765 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 ...
2
votes
2answers
503 views
Can extra-solar gamma rays reach the Earth's surface?
Can gamma rays of high enough energy entering our planet's atmosphere reach the surface (50% probability)?
Or, in other words, is there a window for extremely high-energy gamma rays like for the ...
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votes
3answers
366 views
Why did people expect the number of electrons emitted because of the photoelectric effect to rise with the radiation's intensity?
The number of electrons emitted because of the photoelectric effect
rises with the frequency of the radiation
is not influenced by the intensity of the radiation (As Chad points out, this is wrong, ...
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votes
3answers
1k views
Would wearing clothing that is black on the inside and white on the outside keep you cooler?
The Straight Dope ran an explanation of why nomads often wear black clothing - it absorbs heat better from the body. On the other hand, white clothing reflects sunlight better. Is it possible to get ...
