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Mott Scattering

I had this old homework that I never completely understood. A scatterng experiment is performed with electrons ($E_0=450$MeV) colliding at an atomic nucleus.Following form factor is measured $\left |F(...
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0answers
59 views

Rutherford Backscattering spectrometry [duplicate]

I recently read about Rutherford Backscattering spectrometry and stumbled upon following equation $$\frac{d\sigma}{d\Omega}=\left(\frac{Z_1Z_2e^2}{8\pi\epsilon_0mv_0^2}\right)^2\csc^4(\frac{\Theta}{2})...
1
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1answer
47 views

Direction of neutron scattering

When neutrons interact with matter scattering, what direction to they scatter? Is it random, or some probability distribution of directions? I'm trying to understand why neutron reflectors reflect ...
2
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1answer
34 views

(What causes) the *other* Compton edge?

The question If one exposes a scintillator to a gamma source, one will observe two features for each characteristic energy in the source: a photopeak, due to complete absorption of photons, and a ...
1
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0answers
72 views

Example of calculating phase shifts in scattering theory

I have an extended question to this post: Phase shifts in scattering theory I have read it and also went over the formalism in Sakurai's, Shankar's, and Griffith's. I am now trying to look for ...
3
votes
1answer
42 views

Thickness of a target bombarded with deuterium

I need to calculate de thickness of a sheet of Zinc that is being bombarded by deuterium nuclei. I'm given that the fraction of nuclei dispersed below $\theta=90º$ with $T=8MeV$ is $0.9999$ and the ...
1
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2answers
104 views

If the probability that an alpha will deflect is $1/10000$, for $n$ layers, is the probability is only $1/10000n$?

I have attached a picture of an extract I read on Wikipedia (also in the AQA A-Level Physics specification and textbook). It says that 1/10000 alpha particles deflected in the alpha particle ...
0
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1answer
34 views

Rate of reaction of collision in relation to the geometric cross-section

I am reading "Particles and nuclei : an introduction to the physical concepts / Bogdan Povh" and on page 44 of the book there is a section about the geometric cross section in a idealised scattering ...
0
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1answer
47 views

Average differential cross section of neutron scattering on diatomic molecules

I am using Born Approximation to calculate this problem and I've already got the solutions to both of the problems. What confused me is the definition of the unpolarized differential cross section: $$\...
1
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0answers
40 views

Which structure function is G(x)?

I found a question about structure functions where they ask what is the $F_2(x)$, $xF_3(x)$ and $G(x)$ shape as a function of $x$ (for a given $q^2=10$ GeV$^2$) and also as a function of $x$. I found ...
-1
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1answer
66 views

Deep Inelastic Scattering cross section: Smearing of the $F_2(x)$ graph and relation of form factors with Fourier Trasform of nucleon distibutions

Consider Deep Inelastic Scattering cross section $$\frac{d^2 \sigma}{d \Omega d \nu}=(\frac{d \sigma}{d \Omega})|_{Mott} \{ W_2(Q^2,\nu)+2 W_1(Q^2,\nu) \tan^2(\theta/2) \}$$ It is said that the ...
3
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0answers
54 views

What Exactly is the “Optical Limit” in High energy hadronic collisions?

I am a little confused about what "Optical Limit" means in the context of hadronic diffraction. In some text it says that is the case where $A$, $B$ goes to infinity, where $A$ and $B$ are the ...
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0answers
193 views

Electron scattering to find the nuclear radius

Why we use the minimum diffraction angle here to find the nuclear radius? I know how to find the radius (using the equation $d\sin(\theta)=1.22(\lambda)$), but I don't know why we use the first ...
17
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2answers
2k views

Neutron discovery, why it couldn't be gamma ray? or other photon?

During the discovery of the neutron by J. Chadwick it was observed that something is emitted from beryllium when bombarded by alpha particles that could knock out protons with 5.7 MeV from a paraffin ...
1
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1answer
54 views

Theoretical framework of nucleon exchange reactions

There has been a lot of interest in nucleon transfer reactions in the recent past. Is there any theoretical framework to understand this? I am hopefully looking for literature that could potentially ...
0
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1answer
436 views

Forces on an Alpha Particle travelling close to a nucleus

Above is a picture of a diagram, figure 3 showing an alpha particle fired past a lead nucleus. The question stated: Figure 3 shows the path of an alpha particle close to the nucleus of lead. Draw ...
30
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3answers
4k views

How did Rutherford conclude that most of the mass (as well as the positive charge) was concentrated in the nucleus?

Geiger and Marsden's experiment led Rutherford to believe that the positive charge and most of the mass of the atom was concentrated in a small region. I understand what led him to conclude the way ...
1
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0answers
111 views

Electron scattering on nucleus, form factor

I am currently studying the scattering of an electron on a nucleus... In my book it says that the form factor can be measured in electron scattering experiments and is given by : $F(q^2)=\frac{d\sigma ...
2
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2answers
2k views

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 ...
0
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1answer
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 (...
2
votes
2answers
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 $\theta = 0^\circ$...
1
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0answers
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. ...
1
vote
1answer
670 views

minimum hyperbolic distance for Rutherford Scattering

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{\...
2
votes
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 ...
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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 ...
1
vote
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?
0
votes
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 ...
0
votes
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 ...
2
votes
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 ...
1
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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 ...
8
votes
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 ...
8
votes
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?
1
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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.
4
votes
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} + (...
-1
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2answers
2k views

Angle of deflection of an atomic nucleus [closed]

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?