Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.

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What makes a nucleus unstable?

My question is simply that - what makes a nucleus unstable? What exactly causes a nucleus to start breaking apart in the first place? Is it the Coulomb force between the neighboring protons? I'm just ...
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297 views

Questions on beta-decay

According to my textbook, for all the beta decays, it is required that the mass of the original atom to be heavier than the mass of the final atom. Is this due to the fact that all the beta decays ...
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516 views

Temperature Dependence of Fission

I've always heard fusion depends on incredible temperatures and pressures, but I'm curious what the temperature dependence of fission is. For instance, if I had uranium and heated it to a ...
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Does the fact that protons and neutrons have larger mass than electrons mean they're bigger in size?

and so if a proton is so larger than an electron doesn't that mean it has a shape? What would be the shape of a subatomic particle? are they spherical?
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What are good examples to demonstrate Einstein's mass-energy relation [duplicate]

According to Einstein's mass-energy relation mass and energy are interchangeable. Can you provide some examples where: Mass gets converted into energy. Energy gets converted into mass.
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134 views

Could there be a correlation between the Island of Stability and dark matter?

I can only boast of my passion for science and not of any credentials. I ask because I am curious, and it is not the type of question one can easily Google! What if the key to discovering and ...
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300 views

Fukushima vs Thorium [closed]

This is not a question about traditional nuclear power plants vs the thorium based. But about the Fukushima plant itself and the very negative environmental effects from its meltdown of reactors 1 and ...
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2k views

How does electron capture occurs?

Electron capture is a kind of decay by which a nuclear transformation takes place. Below is an example of it. $$ _{29} ^{64} \text{Cu} + e^- \rightarrow _{28}^{64} \text{Ni} $$ Of course, nucleus ...
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272 views

Isotope properties plotting tool?

I'm looking for something that will generate scatter plots comparing different properties of isotopes. Ideally I'd like some web page that lets me select axis and click go but a CSV file with lost of ...
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40 views

Cause of radioactivity

If Uranium-238 is hit by a neutron, it splits into different parts. My question is (a) Why throwing a neutron will destroy the equilibrium? Rather, should it not help maintain it? (As neutron is ...
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65 views

Can we use a particle accelerator to create elements?

i'm a student of 11th grade. i studied about working of particle accelerators, cyclotrons in particular in a chapter of electromagnetism. i also read that the whole periodic table after element number ...
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139 views

Why don't neutrons cluster on their own?

"The answer lies in their one part in a thousand extra mass. Adding neutrons costs a little in mass, and in Einstein $E=mc^2$ implies that mass equates to energy. So it costs energy to add ...
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How is an electron “recycled” in a neutron?

A proton is made up, they say, by 2 up and 1 down quark, drowned in a sea of virual paricles: when an electron is captured this process thereby changes a nuclear proton to a neutron and ...
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Question about calculating age of a uranium and lead containing object, based on the ratio of uranium-to-lead

I realize this is probably going to sound so stupid, but... here goes: Radioactive decay: We know that we can calculate the age of a uranium containing object by the uranium-to-lead ratio, due to ...
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43 views

Probability of $\alpha$-decay

In standard Gamow model we assume that $\alpha$ particle is already in the nucleus, i.e. four nucleons are "glued" together and this particle is emitted. So, we assume that the probability of the ...
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105 views

How effective are nuclear weapons in space?

When a nuclear bomb explodes it heats up the air surrounding it and a destructing shock wave is generated. Consider the same bomb exploding in space. This would be the case for example if we tried to ...
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34 views

Nuclear transmutation of radioactive waste using high-energy neutrons

How likely does this work: Accelerate neutrons to as high energy as possible (particle accelerators/ cosmic rays ...) and hit (small samples of) our radioactive waste with it such that it is converted ...
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105 views

How do protons and neutrons interchange?

I recently read in a book that a nucleon with +1/2 isospin is a proton and if the isospin is changed to -1/2, it is a neutron, so it is the same particle in different states. If a proton has a ...
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579 views

Does lithium-6 “decay” when hit by a neutron?

I am talking about the nuclear reaction $$ ^6\text{Li} + n \rightarrow\ ^4\text{He} +\ ^3\text{H} + 4.78\text{MeV} $$ A neutron hits a lithium-6 nucleus and together they form an alpha and triton ...
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356 views

Is there a maximum number of neutrons of an isotope?

I wondered whether there is a maximum number of neutrons in an isotope. Or is there no maximum number? So, can an H-75 atom exist?
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206 views

Radioactive decay law and the exponential model, is it always valid?

The law of radioactive decay reads $$ N(t)=N_0e^{-\lambda t}$$ Is it valid when there is less than 1 nucleus or particle to decay? Obviously, it is nonsense to consider that we have 1/2 of nucleus ...
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179 views

Would a Nuclear bomb have any effect on the sun that could damage the earth?

I was asked this recently and wasn't sure. The power of the sun is much more powerful than that of a Nuclear explosion but the question was what is the worst that could happen, we are assuming a ...
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80 views

Falling metal cylinders more devastating than a nuke?

I just saw G.I JOE - Retaliation. In the movie the bad guys (spoiler alert) Could this device cause more destruction than a nuclear weapon? If so, how?
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Is it possible to manufacture Helium?

Helium is a scarce resource, as it escapes the atmosphere over time. If we run out of Helium deposits, will it be possible to manufacture more helium through nuclear fusion or another nuclear process? ...
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Ba K Lines in a Cs-137 gamma ray spectrum

I'm looking at a spectrum for the gamma ray spectrum of a 137-Cs source and I'm not sure where the peak in the lower energies of ~32keV comes from. I understand that it's to do with some sort of ...
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2k views

Why does mass change in to energy during a nuclear change?

I have been doing some research on nuclear changes and I have found that the energy released during a nuclear change comes from a minuscule amount of mass that is converted in to energy. After making ...
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812 views

Calculate/estimate power of a fission bomb

I have some questions about the released energy and power of a nuclear fission bomb. What are the key dependencies of the power of a fission bomb? Is it true that the power of a fission bomb depends ...
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396 views

Why isn't heavy water much heavier, and what use is it for fission reactions?

With confusion I experienced recently, I'd like to clarify some stuff for myself about nuclear energy, that I find are usually not properly explained. What exactly is heavy water, just water where ...
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161 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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53 views

Atomic bomb explosion [duplicate]

What are those vertical filaments that form in the air whenever an atomic bomb is detonated? They are clearly visible in this movie at 3:08.
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27 views

Should I see evidence of neutron induced gammas on a background spectrum?

If I am looking at a background gamma spectrum taken from a neutron spallation source whilst the beam was off (IE in a shutdown period), should I expect to see emissions coming from neutron induced ...
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96 views

Safety of Polonium Isotope source

I saw a YouTube video by a guy demonstrating Geiger Counter use and one of his radioactive test sources was a disk with Polonium. He casually mentioned that this was the poison used to kill that ...
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32 views

Notation on chart of the isotopes

I recently purchased a complete chart of the isotopes, (this one: https://shop.marktdienste.de/shoppages/produktuebersicht.aspx ) and have it on the wall next to me in work. The different coloured ...
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82 views

Length of time interval for an atom in excited state to drop to lower energy level [duplicate]

This is either a basic question or one that doesn't make any sense, but here goes. If I have an atom in an excited state (1st energy level or 2nd or more), how long does it take to drop to a lower ...
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60 views

Nucleon-meson interaction

Suppose interaction lagrangian between neutron-proton doublet and $\pi$-mesons: $$ \tag 1 L_{\pi pn} = \bar{\Psi}\pi_{a}\tau_{a}(A\gamma_{5} + B)\Psi , \quad \Psi = \begin{pmatrix} p \\ n\end{pmatrix} ...
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58 views

Nuclear decay of V-48

I have a question on the "decay" of Vanadium-48. The reason it's in inverted commas is because I'm not sure whether decay is the right word. Basically what I'm trying to work out is whether it's ...
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132 views

Why is isospin so useful?

I'm currently reading about isospin in nuclear physics, and I know how to calculate it, and all the math, but I'm actually not sure WHY it is so useful? Can anyone come with some examples where not ...
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60 views

Ground state of 113Sn from shell model

The shell model predicts that the ground state of 113Sn with 63 neutrons would have J=5/2+. But the ground state is taken to be 1/2+. What is the reason behind that? Has it got something to do with ...
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463 views

What's the idea behind Wu's experiment?

Madame Wu discovered the parity violation in beta-decays. To do so, she took some Co-60 nuclei, which decay via beta-decay in Ni-60 with emission of electron, antineutrino and 2 gamma rays. She ...
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108 views

Deformation parameters of a nucleus

How are the deformation parameters (quadrupole, hexadecapole etc) of a nucleus mathematically related to the reduced transition probabilities $B(El)$ values obtained experimentally?
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Why do nuclear multipole moments of charge density vary with isotopes?

Why do some isotopes have different quadrupole/octupole moments, when these moments of charge density should be independent of mass?
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Energy from 1 gram of fuel in a nuclear power plant?

It might go without saying, but I am asking about a fission reactor. I assume the fuel still has mass after it is used. If I am right about that, I can't use e=m*c^2 to answer my question. Hence my ...
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168 views

What is the energy threshhold to produce Cherenkov radiation?

I am in a nuclear course right now and am getting some misleading information from different sources. I am trying to figure out what the minimum total energy is that a proton must have in order to ...
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47 views

What process happens in an IT nuclear decay?

I've been researching medical isotopes and alot of them decay by an IT path. Does anyone know what IT stands for? And what physical process is happening? Example: ...
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89 views

Is it correct that whenever energy change, mass also change?

Can I simply claim that, according to the mass-energy equation $E=mc^2$, whenever the energy of an physical object (not necessarily a microcosmic one) changes, its mass also change? Okay, I ...
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90 views

Would it be possible to “recycle” nuclear warheads into nuclear energy? [closed]

The number of nuclear warheads in the world is estimated (!) to be over 16,000. [0] Surely, this stockpile represents a massive threat to humanity. My question is simple. Can we repurpose these ...
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90 views

Identification of massless, chargeless $x$ in a nuclear reaction

On Friday, we had our Physics test. We (the tenth grade students) have the basic introduction to Radioactivity and a few nuclear reactions in our syllabus. In the test, the following question was ...
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142 views

Can we observe proton decay?

I know that the half life of a proton is more than $6.6\cdot 10^{33}$ years (antimuon decay). I have found this data on Wikipedia proton decay but I do not know the probability distribution that leads ...
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247 views

Cobalt 60 beta decay

In the beta decay of an atom of Co60, the radiation you would expect is one or two gamma rays, plus an electron plus an electron neutrino (and in the nucleus Ni60+, if I understand it well). However, ...
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717 views

Strength of strong nuclear force vs distance?

Is there at least an approximation of the decrease in strong nuclear attraction vs distance from the center of the nucleus?