Questions tagged [protons]
A proton is a positively charged particle which is generally considered to be a composite particle comprising of three quarks interacting through the strong force (e.g. in the standard model.)
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If we have a beam of photons and a beam of protons with the same energy, which one will get further inside the human body?
If we have a beam of photons (high energy X-ray) and a beam of protons both with the same energy, which one will get further inside the human body and why? Can this be explaind due to LET (Linear ...
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How to derive the differential cross section in terms of outgoing mass?
In a paper about the Atlas experiment (https://arxiv.org/abs/2103.01918) differential cross sections of $pp\rightarrow ZZ\rightarrow 4\ell$ are being presented. However these cross-sections have the ...
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Does the standard model predict $\alpha_G^{-1}\approx c_5$ for $m_{proton}$? [closed]
Given $$\alpha_G^{-1} = \frac{m_{planck}^2}{m_{particle\ of\ interest}^2}$$
$$particle\ of\ interest = proton$$
$$c_5 = fifth\ Catalan\ Mersenne\ prime = 2^{(2^{(2^{(2^2-1)}-1)}-1)}-1$$
Does the ...
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Where can I find accurate visual representations of atomic nucleus nucleons wave probability functions like I see for electron atomic orbitals?
Note the Wikipedia article for 'Atomic nucleus' was awkward here because first they depict the old concept with protons and neutrons as a bunch of spheres touching each other and in the sub-text ...
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Reducing Inelastic Electron-Proton's Scattering Cross Section to Rosenbluth's Formula
I'm currently studying electron-proton scattering from Halzen & Martin's book (Quarks & Leptons : An Introductory Course in Modern Particle Physics). I found that the cross section for the ...
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Charge congjuation and Transition form factors
Let us consider the transition form factor of proton to Delta (see reference of https://doi.org/10.1103/PhysRevD.100.034001):
$\gamma^{\ast}p \to \Delta$.
Then we should also have the timelike ...
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Condition on debroglie wavelength to probe the proton
What is the condition of the debroglie wavelength of an e.g electron beam such that we can probe the proton?
Do we require that $\lambda < $size of proton or do we require that $\lambda ≈$ size of ...
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Kinetic energy of quarks in a proton
If we say that a proton has a kinetic energy of 50 GeV, can we say that each of the three quarks that compose it have roughly a mean energy of $\approx \frac{50}3=17$ GeV?
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Does free neutron decay create a hydrogen atom?
When a free neutron decays, it is transformed into a proton, an electron, and a neutrino. Does this electron begin to "orbit" the proton, forming a hydrogen atom? Or does the electron run ...
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Is a neutron the mixture of a proton and an electron?
Is a neutron a combination of a proton and an electron either by mass and/or charge?
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Which spinor should be used for an outgoing proton if we treated it like a point particle? $\bar{u}(p)$ (as for electron) or $v(p)$ (as for positron)
Consider the Rutherford scattering $e^-p^+ \rightarrow e^-p^+$
If a proton is a treated as a heavier positron:
$i\mathcal{M}=(-ie)\bar{u}(p_3)\gamma^{\mu}u(p_1)i\Pi_{\mu\nu}(-ie)\bar{v}(p_2)\gamma^{\...
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What contributes most to the mass of the proton?
i'm a bit confused about the origin of the mass of the proton (or other hadrons). It is said that it stems from the renormalization of the current quarks, which have about 1/100 of the mass of the ...
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Has the mass of a proton been calculated from current quarks, through the renormalization process?
That's basically my question. Has the mass of the proton been calculated using QCD and the interactions between the current quarks? Perturbative methods obviously can't be used as they deal with ...
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The difference between neutron and proton separation energy of a nucleus
For a given nucleus, why does the value of the neutron separation energy $S_n$ differ from the value of the proton separation energy $S_p$? One of the reasons that is immediately obvious is that the ...
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Mass energy equivalence of photons
It is said that elementary particles get their mass from the Higgs field. Also 99% of the mass of a proton comes from the strong force binding its quarks together. So we say that the mass energy ...
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How exactly does a proton form from quarks? What is the exact sequence and mechanism?
What are the steps that lead to the bonding of two up quarks and one down quark into a proton? For instance, does an up quark "bind" with a down quark in quark-gluon plasma, which then binds ...
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Do electrons define the element? [closed]
In a nuclear reaction, protons and neutrons are exchanged and the resulting elements have a number of different protons and neutrons that uniquely define the element that we are studying.
However, can ...
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Double Slit Experiment with Protons
Has the double slit experiment been executed with a proton beam? Electrons and photons seem to get all the attention. What about a particle with positive charge, and one said to be composed of ...
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How to understand JJ Thompson's experiment without defining charge via electrons and protons?
I am beginning to learn chemistry/physics, and I have recently read about JJ Thompson's experiment which led to the discovery of the electron. In every source that I've read, the writers note that ...
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Will Hawking radiation violate baryon number conservation around gravitating bodies other than black holes?
Numberous articles discussing a recent research paper suggest that even stars and planets will eventually radiate away their mass like hawking radiation. My question is will this violate baryon ...
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How do protons fuse in the sun?
I know that Nucelar fusion in the sun requires quantum tunneling to occur, as otherwise the Sun's core wouldn't be hot enough to overcome the Fusion barrier.
However while the 2nd and further stage of ...
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Why is the charge on the electron and proton equal in magnitude? [duplicate]
Why is the charge on the electron and proton equal in magnitude?
The charge on electron is $-1.602 \times 10^{-19}$ C and the charge on proton is $1.602 \times 10^{-19}$ C. Their magnitude is the same ...
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How does a nucleus manage to gather the energy to withstand the constant force applied on it from the protons? [closed]
The force repulsing two protons never goes away, meaning that there is a constant force pushing the protons apart forever. Firstly, where are these protons getting the energy to constant apply this ...
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Electric charges type-postive and negative.positive in protons and negative in electrons.elrctric means electrons negative so why do we includeproton [closed]
Electric charges are of two types - positive and negative charges.electrons are negatively charged and protons are positively charged. If the term electric means electrons and electric charge means ...
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Do the currents of charged particles captured by Earth's magnetic field create their own magnetic fields?
Let me try to illustrate what I mean. Consider e.g. a Solar radiation storm (Solar particle event) where high-energy protons are hurled at Earth from Solar flares. I've tried to illustrate my ...
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In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards? [duplicate]
I am teaching year 11 Physics for the first time. In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards?
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Is there a classical radius for the proton?
High energy photons scatter off electrons via Compton scattering. The differential cross section of this scattering is given by the Klein-Nishina formula, which contains within it the classical ...
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Working of MRI in detection of tissues for imaging
why we consider the rotational axis of proton under the action of magnetic field in MRI not electron?
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The proton quantum state
In my understanding of QM I expect the quantum state of the proton $| p^+ \rangle$, say in the rest frame, to be an eigenstate of the QCD Hamiltonian $H_{\text{QCD}}$, which describes the dynamics of ...
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Vertex function QED and Deeply Virtual Compton Scattering (DVCS)
In QED we have one vertex where one line is virtual and the other two are physical:
But recently I came across the so-called Deeply Virtual Compton Scattering in which, after the interaction of an ...
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Why are there no antimatter-antimatter collisions in CERN?
The labs at CERN create anti-Protons, and have collided them with Protons. Anti-Hydrogen is used to study matter-antimatter asymmetry.
Were there any attempts to collide anti-Protons with anti-Protons?...
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How do we know charge is only positive and negative? [duplicate]
Could there be a charge different than that of a proton and that of an electron? Could there be a third type of charge that is not repulsed or attracted by either an electron's charge or a proton's ...
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Help with Shell Model and Pauli Exclusion Principle
As I understand, the occupancy number in the nuclear shell model dictates the number of each type of nucleon that can occupy a specific sub-shell (angular momentum state l).
Note: s, p, d, f ...
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ProtoElectric Effect: How would this work?
In the 'Photoelectric Effect' setup, if I replace the light source with a 'Proton Gun', What would be the result?
I tried to search around and could shortlist a few possibilities, but am not sure if ...
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Is an electron more stable than a proton/neutron?
Is an electron more stable than a proton/neutron under extreme temperature/pressure conditions, like several 100 millions K?
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How electron, proton and neutron have mass numbers
As far as I know, the mass number of an atom means the amount of protons and neutrons it has. For example, the mass number of Sodium (Na) is 23 since it has 11 protons and 12 neutrons. Then how ...
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Why can't we slap a proton for instead of using particle accelerators?
Very stupid question, but since the mass of a hand is very large compared to a proton, one should be able using a solid slap to accelerate a proton to ultra-relativistic speeds. If I consider a ...
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Why does deuterium fusing with a proton produce a gamma ray?
For the pp chain, the second process is listed as the d(p,γ) 3He reaction: D + p --> 3He + gamma ray.
I cannot find an explanation why a gamma ray is created in this process. Can anyone explain why ...
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How do we know that electrons and protons have the same magnitude of charge? [closed]
During the Mulliken experiment, that I was reading, it was found out that the charge on the oil droplets were an integral multiple of the value 1.6 × 10^-19. We claimed it to be the charge of one of ...
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Why are nuclei with large numbers of neutrons only stable with correspondingly large numbers of protons? [duplicate]
Large numbers of protons need to be separated by neutrons, otherwise they repel....
But why do nuclei with large of numbers of neutrons only remain stable with a relatively, correspondingly large ...
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Is there a physical reason the fine structure constant should be 4 times ratio of a proton's classical to charge radius? [duplicate]
What is the physical relation, if any, that explains the factor of 4 in:
$\frac{\alpha}{4.001\pm 0.009} = \frac{r_{p_{Classical}}}{r_{p_{RMSCharge}}}$
where
$\alpha$ is the fine structure constant
$...
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Why aren't electrons composite particles like protons are? [closed]
I asked this question previously, but it was closed. I would like to try to explain what I am asking in a better manner.
Protons and electrons are opposite in charge: one is positive, and the other is ...
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Do protons have a shape?
They are often assumed to be balls and spheres in high school textbooks and exams and I had never questioned this until somebody complained to me that modern physicists are obsessed with balls.
Do ...
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Virtual Quarks Inside the Proton
I just watched a video that claims that the standard 2U and 1D quark inside a proton is too simplistic. Basically the quarks inside are virtual quarks, that are constantly changing. There are times ...
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Can an evaporating black hole emit protons with an energy beyond the GZK limit?
There are protons reaching the earth with energies that exceed what their interaction with the cosmic microwave background should allow, the so-called GZK limit.
Could an evaporating black hole emit ...
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Do experiments of proton radius measure it to be larger at higher speeds?
Do the experiments conducted to measure the proton radius consistently measure it to be larger when the proton has higher momentum?
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What are the dimensions of the proton's substructure?
I was looking over the "Visualizing the Proton" videos that MIT put out a few years ago, where the collision data from CEBAF, etc. was turned into a visual representation of quarks, gluons ...
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Method of Neutral Particle Mass Calculations from Bubble Chamber Images
I am looking into events within bubble chamber images and have come across a stumbling block. It relates to finding masses of neutral particles within bubble chamber images, specifically the mass of ...
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What happens inside a proton?
This post contains 3 questions but they are very similar.
I saw from this question What's inside a proton? and other websites that protons aren't really made up of three quarks, but a lot of ...
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Identifying quark constituents of the proton using proton-electron scattering
Rutherford's scattering experiment of the atom is qualitatively convincing just by the detection of near 180 degree deflection of positively charged alpha particles when shot through the dense lattice ...
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