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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Are protons and neutrons truly spherical and round like they are drawn? [duplicate]
I was watching a documentary "Visualizing the Proton: A Documentary" (link)
And this image of a proton popped up. So that got me my question.
Moreover, what about electrons and other ...
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Could antineutron and pion generate proton? [closed]
We need information and guidance regarding the possibility of two reactions: antineutron + pi+ -> proton and antiproton + pi+ --> neutron. The attached illustration indicates that such reactions ...
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Why don't neutrons and protons have variable half-integer spin?
Protons and neutrons are made up of 3 quarks say Q1, Q2, Q3. Each quark is a 1/2 spin particle. Now, $S(proton/neutron) = S(Q1)\otimes S(Q2)\otimes S(Q3)$. So, shouldn't the proton/neutron have a ...
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Why do quarks that form protons and neutrons result in positive and neutral charge and not a negative one?
The title should be clear enough. To my current understanding, whether quarks form proton or neutron depends on the spin of the quarks. It would make more sense for the three quarks to result in ...
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Calculating Binding Energy of Th 230 nucleus [duplicate]
Ok this is NOT a homework question. But it’s somewhat related. Please bear with me.
In calculating BE of Th 230, I used the rest mass of proton as 1.007276u and rest mass of neutron as 1.008665u (as ...
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What will happen if we keep bringing two protons closer and closer to each other, starting from a large distance?
I am asking this question for theoretical understanding of the topic: What will happen if we keep bringing two protons closer and closer to each other, starting from a large distance?
I understand ...
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Do neutrons have a higher entropy than protons?
Since free neutrons want to undergo beta decay into a proton while protons are relatively stable does that mean that neutrons have higher entropy than protons?
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What does it mean to carry 'a fraction of the proton's spin'?
The proton spin crisis is an open problem in physics regarding the origin of the spin of the proton. The problem is described as some "fraction of the proton's spin" being unaccounted for. ...
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Can an electron be produced inside a proton? [duplicate]
We know that inside a proton there is a sea of quarks, antiquarks and gluons. This happens as the valence quarks emit gluons which then split into a quark-antiquark pairs. These pairs become gluons ...
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Why do protons not show a "classical" mass defect?
An atomic nucleus consists of protons and neutrons, held together by the strong nuclear force (i.e. gluons). The heavier a nucleus gets, the more neutrons have to be added to overcome the increasing ...
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Effects of a hypothetical "proton-decay bomb" for a fictional story [closed]
I'm writing a science fiction story in which I need a devastating weapon of mass destruction that is far worse than nuclear bombs. For some reason, I'm fascinated by the idea of a "proton-decay ...
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Why so much kinetic energy inside a proton?
I'm reading 'Waves in an impossible sea' by Matt Strassler - a very good, popular science book, by the way - and he explains that the rest mass of a proton mostly comes from the kinetic energy of the ...
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Can the protium nucleus be in an excited state?
An electron in protium can absorb a photon and jump to an orbit of higher energy. Is an analogous procedure possible for the nucleus of protium (a single proton)?
Can this nucleus be in an excited ...
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How does pion exchange cause protons and neutrons to be attracted to each other? [duplicate]
I read that neutron and protons are attracted through exchanging pions between each other. However, as far as I understand, they are just exchanging a meson, not any force carriers. What causes them ...
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How can a proton be stable if binding energy *increases* it's mass? [duplicate]
A hydrogen atom weighs 13.6eV less than a proton + electron. This missing energy, which is tiny compared to the rest mass of almost a GeV, was carried off by a photon when the atom formed.
Nuclei show ...
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Does the proton do anything in a simple electric DC circuit? [closed]
Since the valence or free electrons and doing the flowing guided by electromagnetic field, what about the protons that are still stuck in the nucleus inside the wire, battery, resistor what have you ...
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Quantum Chromodynamics (QCD) Prediction of Proton Mass
I’m trying to understand the prediction of the proton mass according to Quantum Chromodynamics (QCD). I know that the proton is composed of quarks and gluons, and that the mass of the proton is not ...
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Are quarks real particles? Or only combination form of leptons inside nucleons? [duplicate]
There are not any free and independent quark in the nature. Collision of many particles inside most powerful accelerators could not produced any free and independent quark but result of collision ...
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Is electric charge dependent on mass of an object? [closed]
I got this question while reading about electrons and protons where electrons having less mass than protons but possess the same amount of electric charge,though negative.
Could you please elaborate ...
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High energy collision of two proton
Suppose there are two protons ( as we have in LHC). One proton is coming from +ve z axis and other from -ve z axis toward the collision point(origin). Both proton collide with equal velocity. Now as ...
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What forces are responsible for the conservation of momentum at the subatomic scale?
When I throw a ball at a wall and it bounces off of it and there is conservation of momentum we can say that the springiness of the ball and the wall is the action reaction force responsible for the ...
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Charge distribution of a proton
I've been studying high-school level physics and I noticed that protons are composed of up-up-down quarks. It is known that fields can be non-uniform due to geometries: Earth's gravity field is not ...
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How do protons transfer from one object to another by induction?
Charging by induction begins with a positively charged object and a neutral object which causes the electrons on the neutral object to be closer to the charged object. In diagrams I saw online, when ...
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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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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 conjugation 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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