Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.
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How do we know that the nucleus isn't a quark-gluon plasma?
The standard picture of the nucleus of atom is that is several distinct nucleons, which themselves are composed of quarks. However, it seems to me like a much simpler picture is that the nucleus is ...
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2answers
545 views
Effect of temperature on radioactivity?
I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity.
Can anyone ...
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1answer
428 views
How come random matrices can predict energy spectra of heavy atoms?
Some of the applications of random matrices is to find the spectra of heavy atoms in nuclear physics which are usually difficult to find otherwise.
How can starting from randomness of some kind, ...
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0answers
90 views
Fukushima Nuclear Plant Running? [closed]
If there had been no tsunami would the Japanese Fukushima nuclear plants be operating today?
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1answer
551 views
What is so special about iron?
I remember reading something about how iron was a highly stable element. Ever since then, I have looked at iron fry pans with new-found respect. However, in a recent discussion I was unable to ...
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2answers
206 views
Is it viable to convert nuclear waste into safe isotopes?
I read that powerful pulsed lasers can change isotopes:
J. Magill, et. al.: "Laser transmutation of iodine-129".
Did anyone estimate what would be the energy costs to transmutate 1 kg of fission ...
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2answers
243 views
What elements can be created in the fusion process of different types of suns?
As I understand it fusion inside a sun can produce heavier and heavier elements until some sort of "nucleus size limit" is reached. As far as I understand, the limit is thought to be reached with the ...
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2answers
232 views
Hydrogen as a fuel in Sun
The source of Sun's incessant energy is hydrogen; which is continuously converting to helium through nuclear fusion reaction releasing energy. Why does not all hydrogen convert into helium in one big ...
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3answers
314 views
The “binding energy” of bonded particles adds mass?
This is a follow-up my previous question. Several of the answers indicated that the mass of a particle (atom, proton, etc.) increase with the "binding energy" of it's component particles - the energy ...
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5answers
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Conversion of mass to energy in chemical/nuclear reactions
Is mass converted into energy in exothermic chemical / nuclear reactions?
My (A Level) knowledge of chemistry suggests that this isn't the case. In a simple burning reaction, e.g. $C+O_2\to ...
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7answers
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Why is there a scarcity of lithium?
One of the major impediments to the widespread adoption of electric cars is a shortage of lithium for the batteries. I read an article a while back that says that there is simply not enough lithium ...
5
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2answers
698 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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0answers
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Energy Levels of 3D Isotropic Harmonic Oscillator (Nuclear Shell Model)
One simple way of detailing the very basic structure of the nuclear shell model involves placing the nucleons in a 3D isotropic oscillator. It's easy to show that the energy eigenvalues are $E = ...
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3answers
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Nuclear physics problem, Why do we use high weight atomic elements?
So as far as I know, nuclear fission uses high weight atomic elements to manufacture power. If the risk of runaway reactions are a major reason for not expanding this technology, why don't we use ...
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0answers
187 views
Does the Standard model allow for radioactive decay prediction? [duplicate]
Possible Duplicate:
Predicting Decay Rates via the Standard Model
More specifically, does (any) current theory allow for approximate or exact predictions of atomic decay rates and types ...
2
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2answers
245 views
Nuclear physics Radioactivity
90Sr has a half life of 28.5y. It is chemically similar to Ca and enters the body through the food chain and collects in bones. It is a serious health hazard. How long in (years) will it take for ...
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3answers
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Protons' repulsion within a nucleus
Do the protons inside the nucleus repel each other by the electrostatic force? If they do, why doesn't the repulsion drive the protons apart so that the nuclei get disintegrated?
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1answer
217 views
The vacuum as trigger
Do the apperance in the atomic nucleus of virtual matter-antimatter particle pairs play a role in the random nature of radioactive decay?
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4answers
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Why do electrons occupy the space around nuclei, and not collide with them?
We all learn in grade school that electrons are negatively-charged particles that inhabit the space around the nucleus of an atom, that protons are positively-charged and are embedded within the ...
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1answer
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$\frac{1}{\sqrt{2}}$|Independent particle Model $\rangle$ + |Strong Interaction Model$\rangle$?
What is an adequate way to understand this simultaneously. One has the underlying assumption that matter is saturated and has the merit of being able to come up with an accurate formula for the ...
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1answer
449 views
Matter-antimatter annihilation
What happens if different size atoms meet? We've just created anti-helium, I think. What if one atom of anti-helium collided with one atom of iron. Would some of the iron be left over as a new ...
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2answers
281 views
Electrical neutrality of atoms
How is it that atoms with equal numbers of protons and electrons are described as "electrically neutral" when the proton is 1,800 times more massive than the electron?
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2answers
981 views
Having the same number of neutrons
Sorry if this is a silly question.
If I understand correctly, for two atoms "having the same number of protons" is equivalent to "being of the same element", while "having the same number of protons ...
4
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2answers
730 views
How often does nuclear fusion occur within the human body?
I'm just curious. I figure atoms fuse occasionally just by chance, like quantum tunneling or rogue waves. Is this true? If so, any idea how often?
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Strongest force in nature
Possible Duplicate:
What does it mean to say “Gravity is the weakest of the forces”?
It is said nuclear force is the strongest force in nature..
But it is not true near a black ...
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1answer
164 views
Radioactive nuclear fuel?
I suppose this is a not-too-bright question but, in a nutshell: why are nuclear fuels radioactive?
With this I mean, which is the connection between being a fissile (or fertile, for that matter) ...
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1answer
206 views
Combining chemical elements
Prof Brian Cox mentioned on Wonders of the Universe when discussing chemical elements that Carbon 12 consists of 6 protons and 6 neutrons, he also mentioned that Helium consists of 2 protons and 2 ...
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2answers
573 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 ...
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2answers
447 views
Iodine isotope question
Quick question for the nuclear engineers/physicists out there
Where does I-134 come from? I cant find it in any of the charts of standard decay products of Uranium fission, but there is tons of the ...
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2answers
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How do we know that some radioactive materials have a half life of millions or even billions of years?
If a radioactive material takes a very long time to decay, how is its half life measured or calculated? Do we have to actually observe the radioactive material for a very long time to extrapolate its ...
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2answers
118 views
Detailed logical steps to show experimentally that radioactivity ionizes air?
Suppose one knows almost nothing about the nature of radioactivity (like the discoverers of this phenomenon).
What are the detailed/rigorous logical steps/arguments to show experimentally that ...
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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?
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2answers
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Nomenclature of hadronic resonances
I have the Particles Physics Booklet and I noticed that the resonances that decay into a nucleon and pion are indicated by an abbreviation. For example $P_{33}$ is associated to the $\Delta (1232)$ ...
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3answers
2k views
Why build nuclear reactors on shorelines?
While not directly a physics question, I can't think of forum better capable of answering my question.
In discussions over Japan's nuclear reactor situation the observation was made that reactors ...
6
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3answers
257 views
References on the non-compositeness of the known elementary particles
What paper(s) or theory(s) describe or prove that the elementary particles that we have determined today cannot be made up of smaller more fundamental particles?
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1answer
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PNMR, Pulsed Nuclear Magnetic Resonance, Experiment
I am writing a lab report for class on PNMR experiment that we did. How come in this experiment we don't worry about the electron spins in our sample? Aren't the electrons affected by the PNMR machine ...
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Why does nuclear fuel not form a critical mass in the course of a meltdown?
A BWR reactor core may contain up to 146 tons of uranium. Why does it not form a critical mass when molten? Are there any estimates of the critical mass of the resulting zirconium alloy, steel, ...
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2answers
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Origin of elements heavier than Iron (Fe)
In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a stars death, I usually hear that once the star begins fusing lighter atoms ...
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1answer
713 views
Conceptual problems in nuclear physics for students?
Is there any good reference for conceptual problems for students which learn nuclear physics first time? I am not searching problems that involve difficult calculations. Quite the converse, they ...
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2answers
435 views
If there is a meltdown at the Fukushima reactors, would the control rods melt also?
According to the reports, the shutdown procedures at all the Fukushima reactors were successful, and all the control rods were fully inserted.
So - if there was a meltdown, would the control rods ...
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3answers
216 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 ...
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2answers
303 views
How much radiation exposure in the US was caused by the 105 nuke tests in the Pacific?
Between 1947 and 1962 the US conducted 105 tests of nuclear weapons in the "Pacific Proving Grounds". I'm wondering how much radiation exposure resulted on the west coast of the US. These were part of ...
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1answer
145 views
Are there notable cases of anomalies in the mass-decay rate relationship?
As a general rule of thumb, massive particles (both composite and fundamental) tend to decay rapidly through the weak force, while less massive particles tend to be more stable. Hence, taus are ...
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0answers
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Long time deviations from exponential decay in radioactivity
Are there any examples of common substances whose decay is not exponential?
We're used to thinking about radioactivity in terms of half-lives. This is a concept that makes sense only for a decay that ...
4
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2answers
302 views
Can the earth's magnetic field be generated by heat from a natural nuclear reactor?
I've come upon Dr. J. Marvin Herndon's theory that the earth's magnetic field is generated by a hot nuclear reactor operating in the center of the earth. This is backed by various papers, some of them ...
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10answers
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Can a nuclear reactor meltdown be contained with molten lead?
If lead can absorb or block radiation, would it be possible to pump molten lead into a reactor core which is melting, so that it would eventually cool and contain the radiation?
Is there something ...
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1answer
248 views
Why does Fukushima pressure rise? [duplicate]
Possible Duplicate:
Why didn't the control rods in Fukushima shut down the reactor?
They say that pressure rises and that this can be dangerous. But why does this happen if the reactor ...
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1answer
627 views
What is the influence of the nuclear leakage in Japan
The recent news says that
Japanese authorities confirmed Saturday that radiation had leaked from a quake-hit nuclear plant after an explosion destroyed a building at the site.
What will be the ...
2
votes
1answer
416 views
How much energy can be extracted from hydrogen?
http://en.wikipedia.org/wiki/B-L says that the difference between baryon number and lepton number is conserved. Ordinary hydrogen has one of each, but turning it into helium releases only the binding ...
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4answers
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Where does the energy from a nuclear bomb come from?
I'll break this down to two related questions:
With a fission bomb, Uranium or Plutonium atoms are split by a high energy neutron, thus releasing energy (and more neutrons). Where does the energy ...
