In chemistry and physics, a nucleon is either a proton or a neutron, considered in its role as a component of an atomic nucleus. The number of nucleons in a nucleus defines an isotope's mass number (nucleon number).
Until the 1960s, nucleons were thought to be elementary particles, not made up of smaller parts. Now they are known to be composite particles, made of three quarks bound together by the strong interaction. The interaction between two or more nucleons is called internucleon interaction or nuclear force, which is also ultimately caused by the strong interaction. (Before the discovery of quarks, the term "strong interaction" referred to just internucleon interactions.)
Nucleons sit at the boundary where particle physics and nuclear physics overlap. Particle physics, particularly quantum chromodynamics, provides the fundamental equations that describe the properties of quarks and of the strong interaction. These equations describe quantitatively how quarks can bind together into protons and neutrons (and all the other hadrons). However, when multiple nucleons are assembled into an atomic nucleus (nuclide), these fundamental equations become too difficult to solve directly (see lattice QCD). Instead, nuclides are studied within nuclear physics, which studies nucleons and their interactions by approximations and models, such as the nuclear shell model. These models can successfully describe nuclide properties, as for example, whether or not a particular nuclide undergoes radioactive decay.
The proton and neutron are in a scheme of categories being at once fermions, hadrons and baryons. The proton carries a positive net charge, and the neutron carries a zero net charge; the proton's mass is only about 0.13% less than the neutron's. Thus, they can be viewed as two states of the same nucleon, and together form an isospin doublet (I = 1/2). In isospin space, neutrons can be transformed into protons and conversely by SU(2) symmetries. These nucleons are acted upon equally by the strong interaction, which is invariant under rotation in isospin space. According to the Noether theorem, isospin is conserved with respect to the strong interaction.
It is supposed that the smallest posible black hole has mass of Planck's mass.
But obviously one nucleon (or an electron) also acts with gravitational force.
If we assume that the smallest possible black hole has really Planck's mass, is here any contradiction that nucleon acts with...
Anyone know the difference between how electron fill the orbitals as opposed to nucleons. And what are the special properties of systems with closed shell characteristics.
What I'm looking to understand is why fission and or fusion result in the release of energy.
I understand that:
By looking at the Binding Energy per Nucleon Curve, due to the strong force acting at very small length scales and falling off as 1/x^3 and the electro-magnetic repulsion of the...
Homework Statement
By analyzing the Binding Energy per Nucleon Curve, and using the equivalence factor 1amu=931.4 MeV, show that a U fission frees energy equivalent to 0.2 AMU.
Homework Equations
E=mc^2
A fission I picked: U-235 + slow neutron ---> 141/56 Ba + 93/36 Kr + 2n...
Quark physics is completely out of my depths but I was wondering if, in a nucleon, they assume certain orbitals like s,p,d,f, ... Does one quark tend toward the center? Is there a valence quark? Do any symmetries form?
Pion Nucleon Scattering and a bit about group theory/ representations
Hello everybody,
I am going through Ryder's book about Quantum Field Theory right now. In the chapter about Pion Nucleon scattering he writes the interaction term like
L_{int}=ig \bar{\psi} \gamma_5 \tau_a \psi \phi^a...
NuTeV "anomaly" : evidence for in-medium nucleon modification
Dear HEP folks,
maybe some of you have missed it :
Isovector EMC Effect and the NuTeV Anomaly
From http://www.jlab.org/news/releases/2009/NuTeV.html
Homework Statement
Show that the antisymmetry of the two nucleon wave function in an oscillator model implies that L + S + T = odd. Secondly would this condition change if one worked in a more general single particle model?
T = isospin
S = intrinsic spin
L = orbital angular momentum...
Well I was talking to my physics teacher because were currently studying nuclear physics. And he likes tellign stories to make his examples more straight foreward. And I asked the question what types of radiations are in nucleaar bombs. Gama, Beta or alpha. He answered me with those three types...
I've been banging my head against the wall for days now trying to figure out how one determines the number of quarks inside the nucleon.
I understand it comes from the fact that the Gross-Llewellyn-Smith sum rule is equal to three:
\int ^1 _0 F_3 ^N (x) = \int ^1 _0 (u_V (x) + d_V (x)) =...
Finding Binding Energy (B.E.) through B.E. per nucleon vs Nucleon graph
Hi guys,
Just a quick question here. When provided with the binding energy per nucleon vs nucleon number graph, how do we calculate the finding energy for a specific nuclide?
I thank you for any help in advance.
-...
Why is the potential energy of a nucleon within the nucleus approximated by 3D harmonic oscillator potential?
Is the 3D harmonic oscillator potential approximately equal to the yukawa potential experienced by the nucleon as a result of all the other nuclei(ie collectively) ?
a) Calculate the average binding energy per nucleon in the deuterium nucleus.
b) The energy that binds an orbiting electron to the hydrogen nucleus is 13.4 eV. Calculate the ratio of the binding energy per nucleon to the binding per electron in deuterium. Which particle is held more tightly...
[SOLVED] Why emit alphas, not other nucleon groups?
Homework Statement
(Advanced Physics; Adams and Allday; Spread 8.18, Question
Section 8.18, question 3)
Why do you think helium-4 nuclei (alpha particles) are often emitted from unstable heavy nuclei whereas bundles of neutrons or protons...
The energy that binds an orbiting electron to the hydrogen nucleus is 13.4 eV. Calculate the ratio of the binding energy per nucleon to the binding energy per electron in deuterium. Which part is held more tightly, the electron or the neutron?
I already worked out the average binding energy...
Homework Statement
For lead N=210 Z=82 Pb (atomic mass = 209.984163 u) obtain each of the following:
(a) The mass defect in atomic mass units
u
(b) the binding energy (in MeV)
MeV
(c) the binding energy per nucleon (in MeV)
MeV
Homework Equations
The Attempt at a...
Okay, I decided to start trying to understand the nulceon and delta resonances. Does anyone have suggestions for a good explanation of how these work? How many resonances are there? How are they distinguished? Etc.
Here's the PDG information...
Homework Statement
I need the mass of the nucelon to do my assignment...:confused:
Homework Equations
The Attempt at a Solution
I tried Wikipedia...and other sites on the Web...it says that the mass of the nucleon is on the order of 2000 times the mass of the electrons...so would...
why electron doesn't fall into nucleon in a atom?you know e has negative charge and nucleon has positive charge and they're very close in a atom, so why not?:confused:
I have one stupid question:
Is it true that the difference of proton and nucleon mass is due to the electromagnetic self-energy of the proton?
The same question about pi^0 and pi^- mass difference.
Hey guys, simple question about binding energy. I'm asked to find the average binding energy per nucleon of Magnesium-26. Now I thought that I would have to use: Binding E = (Zmp + Nmn - Ma) X 931.494 MeV/u. Where Z is the atomic #, N is the # of neutrons, mp, mn, and Ma are mass of proton...