Neutron Definition and 770 Threads

Hey Everyone, I'm working on a question and can't quite get the answer out. QUESTION: Part (a) "\left|\alpha\right\rangle and \left|\beta\right\rangle are the eigenfunctions for neutrons polarized respectively along positive and negative z directions. If the neutron, initially in...

I want to know the reason why the thermal neutrons with energy of 0.0253eV is so important. As far as I know, a neutron with an energy of 0.0253 eV is used as reference to measure nuclear cross sections such as absorption, fission, scattering, etc. And I want to know the details and more...

Homework Statement Solve for the flux distribution using the 1D neutron diffusion equation in a finite sphere for a uniformly distributed source emitting S0 neutrons/cc-sec. My problem right now is that I can't figure out the boundary conditions for this problem. We usually work with...

Problem: A flux of 10^12 neutrons/m^2 emerges each second from a port in a nuclear reactor. If these neutrons have a Maxwell-Boltzmann energy distribution corresponding to T=300 K, calculate the density of neutrons in the beam. Solution: The average velocity of neutrons coming from the...

Homework Statement The equation for the "average" velocity of a gas molecule in a closed container is: Vrms = ( 3 x k x T / m )^ 1/2 where k = 1.38 x 10 ^ 23 Joules/K T is temp in Kelvin m = mass per ion in kg = Atomic Mass M / Avagadro's Number Na so for N2, I...

When paraffin wax (or borated paraffin) is bombarded with neutrons, what does the paraffin emit? (If memory serves me correctly I think it emits protons...?) Also what are typical energies that the emitted particles have?

Simple question, please help. I think it belongs in this forum, though I apologize if there's a nuclear physics forum or somewhere else I should put this. I came across this thread when trying to figure out why electrons don't rest at zero distance away from the nucleus of an atom. So as I...

Dear all, I'm starting to study neutron star accretion and a lot of physical phoenomena coming from different scales come along and a consistent picture is frankly hard to grasp. But for now, a real mind boggling question can't exit my mind. Are Neutron stars, as a whole Quantum, or...

Consider a fissile element whose magnitude is at the order of a neutron. In this situation, how can we derive the point kinetic equations? Thanks everyone.

Hello, Can somebody please tell me in details about the rotation speed of a neutron star? Does it rotate very fast and then slows down? Thanks.

Hello, I want to understand: just as the Crab Nebula is the result of SN 1054 and has a neutron star spinning at the center: (a) Does all supernova produces a nebula? (b) Does all supernova remnant has a neutron star at the center? (c) What is the outcome of Kepler supernova i.e. SN...

Pulsars -- Rotating neutron star produces EM radiation? Hello, If a neutron star is composed of neutrons, which do not carry any electric charge then how it's rotation produces pulsars which are electromagnetic radiation? Thanks.

Greetings to all, I know activity for a Am-Be neutron source. I want to compute strenght source in neutrons/s. Yours advices are welcome. Thank you!

Hi could you please explain me what happens with the atomic structure and overall material structure of neutron absorber rods used in fission reactors? As I imagine when they are used they absorb the neutrons that keep the chain reaction going so to stop the chain reaction hence shut the...

If a proton, a neutron and an electron have the same total energy than rank the the particles in terms of most momentum to least momentum This is the first problem I attempted after learning about special relativity. I used the equation E^2 = \rho^2 c^2 + (m c^2 )^2 Since the energy is...

On decays I have only a preliminary understanding. I was looking up the half life of a neutron for another reason. The value I found for neutron decay for a free neutron was 10.3 seconds. Hope that's reasonably accurate. Anyways knowing that neutrons are stable in a nucleus held together...

can anyone give an example in which a nucleus absorbs a neutron and becomes a stable nucleus? or the combination must break into parts?

Homework Statement About neutron stars we can say that: a) They are newborn stars b) They are generated when a Solar-type star dies c) They are generated when a very massive star dies d) They are in the main sequence Homework Equations None. The Attempt at a Solution I'm...

Part 1----------------------------------------- Ok, the site I have just read through is http://burro.astr.cwru.edu/stu/stars_lifedeath.html one. I have a few questions about it. Firstly, about the fusion of helium into hydrogen... http://burro.astr.cwru.edu/stu/media/fusion.jpg It...

My research is about Design and modeling of beam tube of nuclear reactor for BNCT(Boron Neutron Capture Therapy) application and I need some journals and related books about it.

The following problem appeared on the A2 Edexcel Physics unit 4 exam paper January 2012 question 18. The solution, as given by the exam board, is attached. Question: 18. James Chadwick is credited with discovering the neutron in 1932. Beryllium was bombarded with alpha particles, knocking...

I have been looking for experiments demonstrating neutron interferomerty with protons or electrons instead, and found non. Should there be any difference? I refer to experiments in which, for example, the Mach-Zehnder interferometer is cut from a single crystal.

The mass of proton is 938mev/c2 where as mass of quarks in proton is 11 Mev/c2. Much of the reminder is gluon. But gluon does not have any mass. So how can it be gluon? Also in neutron decay, one d Quark transform itself into u quark by absorbing / emitting W boson. in this case W boson is...

Hi All, Trying to write a simple Monte Carlo code for mono energetic neutrons in a steady state slab geometry in one-dimension. Their is an incident source on the left hand side of the slab and its of length L. I understand how to work out the path length and scattering angles based on...

Hello people, I think the problem what I have is well known in experimental physics. Hope, somebody can helps me, thanks in advance. Here is: There is a source of neutrons with a flux of λ neutrons per minute, which you do not know and want to estimate. You open the detector for one minute...

Homework Statement What is the de Broglie wavelength of a neutron that has fallen 0.60 in a vacuum chamber, starting from rest? Homework Equations Not entirely sure λ=h/mv The Attempt at a Solution I can't figure out what the velocity is, I think it would have to do with the change...

neutron capture --> gamma's Someone could explain me how neutron capture in Gadolinium happens? If a neutron is captured, an energy of about 8 Mev is released in form of gamma-ray cascade (Ʃγ). But... how many gammas are released? I believe the answer will be in form of probability...

in general how to calculate binding energy of neutron star? in simple details, what tricks may be included in such a problem..

As I know, the method to solve neutron problem is divided into two steps now, neutron transport calculation for fuel assemblies and neutron diffusion calculation for whole reactor core, both using specified code such as CASMO and SIMULATE from STUSVIK. I want to know whether the commercial...

Hi, I'm considering the following process n+p→d+\gamma where d is the deuteron and \gamma a photon. I want to find out the energy of the photon. I know it will be much less than the rest mass of the deuteron (1875.666 MeV/c2). Can I simply use conservation of energy here? i.e E\gamma...

Hope mods will allow this. Seeking comments on neutron detection techniques described in the linked paper. Authors are affiliated with China Institute of Atomic Energy, Beijing. This is a LENR paper with no theoretical content. Full text is free to download...

I wrote a paper in the physics department's student newspaper at my school, which described why, in my opinion, I considered a neutron star's surface as the smoothest surface in the universe, I considered the space between the particles at the surface (thousands of times smaller than at TPN...

Does the strong force have any major role in neutrons stars other than obviously holding individual nuclei together? Would low energy neutrons tend to "clump" together in the core?

Deaar all good morning I am very interested to the flux in a slab of extrapolated thickness a, containing distributed sources of neutron. A I have an example in which the source is given as s(x)=S(x+a/2) where S is a constant and x distance from the center of the slab. You mentioned in one...

If Neutron stars are what they are... I mean made of literally only neutrons ...how do they generate such immense magnetic field (of the order 10^8 or something) .. I think the name is somewhat misleading and it ought to have a near half ratio of protons ...But still being so compact how...

I wish to verify a couple of assertions. From the NNDC and other references, it appears that the neutron capture cross section of 3H (Tritium) is zero to a first approximation. This holds true for all neutron energies, including cold neutrons. These statements are equivalent to asserting that 4H...

Hi Everyone, Does anyone know of a tool that can extract thermal neutron cross-section data from endf for all availible isotopes? I'm trying to help my professor compile some data to modernize one of his courses. I'm trying to find a list of capture and scattering cross-sections for a wide...

I was wondering today what is the colour of pure neutrons confined together, I'd guess it's either completely black or white, because it doesn't have the electric orbitals needed to generate different wavelengths. I'm generally guessing it just reflects light and is therefore what... maybe a...

Hello! J(Ω) = ∫n(Ω)vΩdΩ This is a neutron current question. It wants me to figure out the net neutron flux (and direction) through a unit area of the xy plane. It gives an equation for n(Ω) = (1/4π)(1-cosθ), but I am trying to figure out what Ω is inside the intergrand because that is...

In the Wikipedia article "Quantum Gravity", it claims that there is some experimental motivation for finding a quantum theory of gravity. In one of the experiments it cites, neutrons are found to jump between discrete quantum states in the Earth's gravitational potential, similar to the discrete...

This one comes from Duderstadt and Hamilton, Problem 7-3. In multi-group diffusion theory What percentage of neutrons slowing down in hydrogen will tend to skip energy groups if the group structure is chosen such that \frac{E_{g-1}}{E_{g}}=100= 1/\alpha_{approx}. I know that the...

2 closely orbiting massive objects are predicted to deserve the fabric of spacetime so much that they will release a ripple of gravitational waves. When geavitational waves are released, they slowly loose velocity energy and spiral into one another. 2 pulsars were discovered orbiting each other...

The situation is this: In a neutron star the Coriolis force induces Rossby waves, just like on Earth. These are waves with very long wavelength -- like halfway around the Earth -- and very large volume but very little amplitude, like fifty meters. On Earth they have a big effect on climate...

Ive been researching for a while now and i still can't understand why neutrons rich isotopes are unstable. As neutrons act like the glue and hold protons together as they increase the Strong Nuclear force that act upon protons and neutrons, i thought the more neutrons the stronger they would...

Homework Statement Suppose that there is a beam of neutrons with a range of wavelengths. One intends to produce neutrons of single wavelength by the use of neutron mechanical velocity selector. The question is, if the slot in the disk B (second disk) of the selector lags the slot in the disk...

Homework Statement Under some circumstances, a star can collapse into an extremely dense object made mostly of neutrons and called a neutron star. The density of a neutron star is roughly 10^{14} times as great as that of ordinary solid matter. Suppose we represent the star as a uniform, solid...

With beta decay a down quark turns into a up quark + W- results in e- and (anti-neutrino) and up quark turns into a down quark + W+ produces e+ + (neutrino), does the W- and W+ get emitted and then turn into e- + (anti-neutrino) or e+ + (neutrino) or do they stay in the nucleus? How does the Z...

what if...Neutron stars I know likely its been answered but if two neutron stars collid, it wouldn't seem that there combined massess would forum a black hole...if I recall that any matter striking the surface of a neutron star impacts with such violence that there is a massive explosion. So I...

why is hydrogen the only element in the periodic table that lacks a neutron?

If proton decay does not occur, will neutron stars just last for eternity unless something collides with them?