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### What does the term “optical potential” mean?

I have read many times the term "optical potential" in nuclear physics papers. Here is an example paper where it is mentioned a few times. It seems to be explained in these lecture slides as a ...
457 views

### Neutron collision in the laboratory and center-of-mass reference frames

In most reactor theory books I find a statement that neutrons are assumed to elastically scatter isotropically in the laboratory frame of reference. Can someone show in a diagram the two systems (...
650 views

### Rutherford scattering at $\theta = 0^\circ\,.$

Rutherford-scattering can be described as: $$\frac{\mathrm d\sigma}{\mathrm d\Omega} \propto \frac{1}{\sin(\theta/2)^4}$$ As we can see, the mathematical function is undefined at $\theta = 0^\circ$...
386 views

### Calculation of Feynman amplitude for pseudoscalar coupling- gamma five matrix calculations

In the post below I will first state the question, then briefly describe my line of thought and the problem in hand and in the end I will phrase the question again in the light of the description. ...
I saw in a textbook that gave the minimum distance for a hyperbolic trajectory in Rutherford scattering is given by $$r_{min}= \frac{1}{4\pi\epsilon_0}\frac{Z_1Z_2e^2}{2E}\left(1+\frac{1}{sin\frac{\... 1answer 500 views ### Difference between scattering amplitude and scattering lenght I'm studying neutron scattering theory and I noticed that one usually writes the scattered wave as a spherical wave:$$\psi \sim \frac{-b} {r}e^{ikr}$$where b is known as scattering lenght. From ... 1answer 2k views ### Direct vs. Compound reactions I know there are different types of direct reactions like inelastic scattering and such. But is the main difference between direct and compound reactions that one excites (Or at least can) the whole ... 1answer 539 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? 1answer 59 views ### What is the charge/matter distribution? I am a mathematics student who is doing an introductory course in nuclear physics and since the course is rather elementary a lot of the definitions/derivations are skipped which makes it quite tough ... 1answer 239 views ### What is the reduced width amplitude of an unstable state? Particularly used in nuclear physics when describing the lifetime (i.e. partial decay width) of a resonant state (a.k.a resonance) is the term "reduced width amplitude". I have searched online, and ... 1answer 360 views ### Why ingoing and outgoing impact parameters equal in elastic scattering? Take the Rutherford scattering, as for example in this picture: What is the easiest way to show that the impact parameter "b" (see picture) is the same for the ingoing and outgoing trajectories? Are ... 1answer 153 views ### Dual and Multiple scattering of protons in light elements I was wondering whether dual large angle scattering and multiple small angle scattering is of great significance in proton colision with light nuclei in comparison to heavy nuclei. For instance given ... 2answers 7k views ### Electrons in Rutherford's gold foil experiment I have been reading a chapter in my physics text. In it there is Rutherford's gold foil experiment. There it is written that doubly charged helium particles (alpha particles) were projected onto very ... 1answer 259 views ### Importance of MHV amplitudes Why are MHV amplitudes so important? How/where are they used and why do people keep trying to rederive them in many different ways? 1answer 57 views ### What is pulsed neutron diffraction? I have tried a google search and checked my condensed matter books but I can't find out what pulsed neutron diffraction is and how it differs from inelastic neutron scattering. 3answers 3k views ### Does the Breit Wigner formula apply to intermediate virtual particles? Breit Wigner Formula describes the cross section for interactions that proceed dominantly via a intermediate particle (O*) A+B → O* → C + D:$$σ = \frac{2\Pi}{k^{2}}\frac{Γ_{i}Γ_{f}}{(E-E_{o})^{2} + (...
when firing a proton (for example) to an atomic nucleus, from a distance $D$, the deflection angle of the proton $\alpha$ to the type of changes atomic nuclei? or always constant?