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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What is the difference between a neutron and hydrogen?

Differences? They are both an electron and a proton, since the neutron decays to a proton and an electron, what's the difference between a neutron and proton + electron? so is it just a higher binding ...
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Charged particle singularity

Is it possible to manipulate magnetic/electric fields, similar to magnetic confinement technologies/penning traps, to compress charged particles into black holes?
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Right Hand Rule for Proton Magnetic Field

I thought that right hand rule was for find the magnetic field generated by a current, where your thumb point in direction of the current. However, I was watching something that said we can curl our ...
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If protons and electrons had similar masses

If electrons and protons had the same mass, would they still be in a stable orbit around their barycenter, or would they eventually collide? Similarly, a positronium(or protonium) only lasts extremely ...
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Can neutrons be synthesized purely from protons and electrons?

Can neutrons be synthesized purely from protons and electrons? Note: I'm looking for reactions that do not require neutrinos or any particles besides just protons and/or electrons as reactants.
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Spinor normalizations in Breit-frame: electric and magnetic form factors

We usually have the normalization (see e.g. page 110 in Halzen & Martin "Quarks and Leptons") $$u^{(r)\dagger}u^{(s)} = 2E\delta_{rs}$$ which leads to $${\bar{u}^{(s)}}u^{(s)} = 2m. $$ ...
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Are the electric charges of an electron and a proton equal or approximately equal? [duplicate]

I read in Auletta's quantum mechanics (section 11.2) that the charge of the proton is, apart from the sign, approximately equal to that of the electron.. What ...
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Construction of Bound states in Lattice QCD

How the proton state is found and renormalized in lattice QCD? Is there any literature shows the method step by step? What about other bound states in QCD if we somehow know their quantum numbers?
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Formation of atoms [closed]

If a Proton goes toward an Electron with a trajectory that forms a circular motion, these particles will form an atom ?
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Are there new states of matter at ultrahigh temperatures and densities?

Under extreme energetic conditions, matter undergoes a series of transitions, and atoms break down into their smallest constituent parts. Those parts are elementary particles called quarks and ...
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What is meant by Proton Structure Function?

I am going to embark on a project involving deep-inelastic scattering but first I am trying to do some really basic background reading to get me up to task. My only background in particle physics is ...
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Why is free neutron unstable but free proton is stable?

Aren't they basically made up of the same stuffs (quarks) in almost the same configuration?
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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 ...
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418 views

Pion production in proton-proton collision

Why is $\pi^0$ created in the high-energy collision $p+p\to p+p+\pi^0$?
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What is charge? [duplicate]

I know this isn't the right place for asking this question, but in other places the answers are so awfull.. I'm studying eletricity, so, I start seeing things like "charges", "electrons has negative ...
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1answer
96 views

Calculate speed of proton at infinity [closed]

I have this problem to solve: Two protons are on the x axis at x=-1 and x=0. An alpha particle is placed at x=2, and the proton on the left is released, find its speed at infinity. I know that this ...
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39 views

Proton gas density

As far as I know the lightest gas is hydrogen due to low mass of its nucleus, but what if we were to somehow strip hydrogen atoms of electrons and enclose protons in a container made of teflon (high ...
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2answers
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How can we get the mass of an uncharged proton?

How can we get the mass of an uncharged proton, i.e. how varies the mass of the charged proton if i remove the electric charge? For the isotopic spin theory neutron and proton have the same mass and ...
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0answers
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The Magnetic Field around the Proton Beams in the LHC

How would one most appropriately model the magnetic field around each bunch of protons in the LHC at maximum operating speed? Is the assumption of a wire of the same length of the beams (~30cm) with ...
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3answers
715 views

Why is a proton assumed to be always at the center while applying the Schrödinger equation?

Why is a proton assumed to be always at the center while applying the Schrödinger equation? Isn't it a quantum particle?
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How does beta+ decay actually occur? [duplicate]

I'm having difficulty in understanding beta plus decay. How can a proton which has slightly less mass than neutron transform into a neutron, positron and neutrino? Form where does the extra mass for ...
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What happens to the electron companions of cosmic ray protons?

If primary cosmic rays are made mostly of protons, where are the electrons lost, and does this mean that the Earth is positively charged? Does the sun eject protons and electrons in equal number?
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Density of a proton

I was doing some exercises the other day, when I came across this question in my book: A proton weighs about 1.66 x 10-24 g and has a diameter of about 10-15 m. What is its density in g/cm3? ...
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70 views

Why do electrons and protons attract each other? [duplicate]

In the end, are they not a condensed form of energy? I want the 'Why' to go as far as it takes. Where it ends? What are the constituents of the electron and proton, that make them attract each ...
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Why does amount of protons define how matter is?

My question might sound convoluted but my mind is twisting right now so my apologies in advanced. Why is it that when I have one proton and one electron it is Hydrogen a clear flammable gas, and ...
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1answer
371 views

Why is the charge on protons == to charge on electrons? [duplicate]

I am not a expert on physics, just another high schooler, so sorry if the question is obvious. This is something I've been wondering about for a while. Why is the charge on a proton equal but ...
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1answer
278 views

Is a free proton a positive Hydrogen-1 ion?

The Hydrogen-1 isotope is a form of hydrogen with 1 electron, 1 proton, and 0 neutrons. If that isotope were to lose its electron (thus being a Hydrogen-1 ion with a positive charge) what would be ...
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The life of proton

I have two questions regarding protons 1) Wikipedia says Mean lifetime of a proton $>2.1×10^{29}$ years (stable) Obviously this means practically nothing happens to a proton, but what does ...
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Charge of electrons and protons

I have a question which reads: "A conductor has a charge of $9.6 * (10)^{-19}$ coulomb. The conductor will have- " The problem I face in this question is due to not knowing the exact value of ...
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Ionizing an atom with a proton

What happens when a proton collide with an atom? How does the ionization occurs, assuming the proton has enough kinetic energy? How much energy is required for the proton to enter the atomic nucleus, ...
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1answer
127 views

How can one calculate the gamma-ray energy spectrum for proton-proton collisions?

How does one calculate the the energy spectrum of gamma-rays produced by a proton-proton collision? I'm at a complete loss.
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What's inside a proton?

What constitutes protons? When I see pictures, I can't understand. Protons are made of quarks, but some say that they are made of 99% empty space. Also, in this illustration from Wikipedia, what's ...
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1answer
212 views

What makes the quarks stay inside the proton?

Inside a single proton for example, what is the force(s) that keeps the quarks together? Why don't they leave the proton? If they do, how does that even happen? And maybe an additional sub question: ...
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1answer
179 views

What are the strongest sources of collimated neutrons and protons?

I am imagining an unusual experiment which will require intense beams of either protons or neutrons. The experiment would work better with neutrons, but neutron sources are much weaker messier so I ...
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Proton Radius Puzzle, Is it possible that proton's radius differ depending on how you measure it? What does that even mean?

I just read this NewScientist article, and I was stunned by its results. So I found the original paper here on arxiv. In the introduction of the paper it is stated: The recent determination of ...
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Quark Radius Upper Bound

If quarks had internal structure (contradicting current beliefs), what is the lowest upper bound on their "radius" based on current experimental results? If possible, I'd prefer to only consider ...
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How do I know the proton isn't made of 3 anti-down quarks?

I have a proton, how do I know that it is made of 2 up quarks and 1 down quark or if it is made of 3 anti-down quarks, each with different color charges? This question is also applicable to the ...
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Is a proton collision (collisions like in the LHC) visible to the human eye?

I was curious if a proton collision is visible to the human eye. (This might sound like a really basic question and forgive me if it is. I am very inexperienced in Physics and just wanted an answer ...
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Why is Neutron Heavier than Proton? [closed]

This is Neutron decay: $$n^o \to p^+ + e^- + \overline {\nu_e}.$$ and this is proton one: $$p^+ \to n^o + e^+ + \nu_e$$ so when the $e^+ =e^-$ and $\nu_e=\overline {\nu_e}$ why $n \not= p$? my ...
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Who (and Why) started the “electrons are negative, protons are positive” convention? [duplicate]

For some reason everyone labels electrons using a minus sign and protons using a positive sign, even though the opposite seems more intuitive: Who started the convention that electrons should be ...
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If the measurement of the proton size is correct and it is lower that it was expected than what are the theoretical implications?

In the press release of the recent measurement of the proton structure, they barely mention various theoretical explanations for the effect. What is the most likely (not assuming now that the ...
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Stable Nuclei - Deviation from equal protons and neutrons

While studying the semi-empirical mass formula for nuclei, I came across an "asymmetry term" whose function, as far as I understand, is to build in the fact that nuclei "prefer" to have equal numbers ...
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467 views

Difference between atom and elementary particle questioned

Hydrogen ion doesn't have one electron which clearly mean that it has only one proton..So hydrogen ion is only a proton. Am I right, please make it clear. If hydrogen ion and proton are same that how ...
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Total positive charge in the Universe

In their last homework, some of my students miscalculated a charge to be $10^{20}$ C over a squared meter and I was wondering if there was as much positive charges in the entire Universe. It would do ...
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1answer
128 views

Do protons in the beam on LHC interact with photons?

Do protons in the beam on LHC interact with photons? I wonder how a beam would look from outside. Is there a photo of a proton beam?
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Empirical bound on sum of electron and proton charge

Followup to "Why do electron and proton have the same but opposite electric charge?". It is argued that even a tiny residual charge would result in huge amounts of electricity in bulk matter, ...
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Spin and Parity of $^{17}_8 O$ excited states

$^{17}_8 O$ quoted here has a spin of 5/2 and parity of +1 for the ground state, I agree with this, the unpaired neutron is in the $1d_{1/2}$ state so l = 2, spin = 5/2. Now I want to figure out the ...
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Protons' repulsion within a nucleus

Do the protons inside the nucleus repel each other by the electrostatic force? If they do, why doesn't the repulsion drive the protons apart so that the nuclei get disintegrated?
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Is there a direct relationship between an isotope's neutron count and radioactivity?

In my textbook, it lists isotopes of Carbon: C-12, C-13, and C-14. It noted that C-14 is radioactive (C-12 and C-13 are not). Is there a direct relationship between the number of neutrons and an ...
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How much would the LHC beam be attenuated by the atmosphere?

As I understand it, the completed Large Hadron Collider (LHC) will ultimately have a proton beam with $2,808$ bunches of $1.15 \times 10^{11}$ protons each at $7$ TeV, giving a total beam energy of ...