Homework Statement
A pion traveling near the speed of light hits a nucleus and travels an average distance of 3.5fm before interacting. Estimate the time req. for the strong force to interact.
Homework Equations
The Attempt at a Solution
So are they saying that the pion hits the...
So I know the neutral pion decays as
\pi \rightarrow \gamma\gamma
my question is though, what forbids this from being an electromagnetic decay? I know it is not decaying via the strong force as there are no quarks resulting from decay. However, I do not see what forbids this from decaying...
Homework Statement
The neutral pion is an unstable particle that decays very quickly after its creation into two photons (“particles” of light: v = c, mo = 0). The pion has a rest-mass energy of 135 MeV. Consider a pion that has a kinetic energy of 90 MeV
1) Determine the v of this pion...
Hi,
I have a question about this decay: \pi^- \rightarrow e^- \overline{\nu_e}
there is a factor:
1 - \frac{v_e}{c}
what are these values, v_e,c, and why this quantity is equal to:
\frac{m^2_e}{m^2_\pi + m^2_e}?
Thank you
Ciccio
Quick question. If particles that mediate interactions are called gauge bosons, why isn't Pion considered a gauge boson. I'm pretty sure I've come across a few interactions mediated by it.
Hello! I'm afraid I've asked this before, a while ago, but I still don't completely understand. It's not a homework question as such, but I thought this might be an appropriate place to put it.
Homework Statement
Why is it that pions decay via pi^+ --> mu^+ + antimuon neutrino 98% of...
Homework Statement
The question is from "Advanced Physics" by Adams and Allday. It is from section 9 "The Physics of Particles", "Practice Exam Questions". It is question 10. The level of this study is between school and University.
I am uncertain about the answer to part c, ii (3rd...
Homework Statement
What is the speed of a pion if its average lifetime is measured to be 4.91E-8s? At rest, its average lifetime is 2.60E-6s. What is the particle's lifetime at rest?
Homework Equations
\Delta t = \Delta t0 / \sqrt{1-(v2/c2}
The Attempt at a Solution
I don't...
Hello! I was just wondering something...
Why is it that a negative pion always decays into a muon and antimuon neutrino? Why not an electron and antielectron neutrino? (and the same for a positive pion)
Any answers would be grately appreciated :-)
Samantha
How is it that \pi\^{\pm} have charges \pm e and \pi\^{0} has a charge of 0? The \pi\^{+} has one up quark and an anti-down quark, which doesn't add up to zero (same deal goes for \pi\^{-}, and the \pi\^{0} has a linear combination that doesn't seem to add up to zero.
Where have I gone wrong?
Problem:
A group of 'pi' mesons (pions) is observed traveling at speed 0.8c in a particle physics laboratory. (a) What is the factor 'gamma' for the pions? (b) If the pions' proper half-life is 1.8x10^-8 s, what is their half-life as observed in the lab frame? (c) If there were initially...
I have studied that the hadronic matrix element of pion decay
(Pi+->mu+ anti muon neutrino) is given as
<0|ubar gamma[mu](1-gamma[5])d|pion>.
The vector current does not seem to contribute, because it cannot connect a state of unnatural parity to hadronic vacuum. Only the axial and...
The positive W boson decays to a anti-muon and a muon neutrino, it should be a weak interaction.
And the positive Pion can decays to a anti-muon and a muon neutrino, too.
But the lifetimes of them are totally different, so why?
I know the positive Pion is composed of two quarks, but could you...
Hello, I understand that the non-zero (or non-small) rate for \pi^0 \rightarrow \gamma\gamma was historically a big motivation for the non-conservation of the axial current. I've been trying to work on problem IV.7.2 (p. 252) in Zee which asks to show that this amplitude vanishes if \partial_\mu...
Hello! I have to hand in this coursework tomorrow and I just wanted to check I had done it correctly so if someone could have a look I'd be really grateful... It's quite long...
Homework Statement
A negatively charged pion \pi^{-} has mass m=140MeV/c^{2} and lifetime 2.6 x 10^{-8}s.
a)...
Hello.
I've been having a hard time finding information about the following reaction:
e^{-}+n\rightarrowe^{-}+p^{+}+\pi^{-}
I hope you could give me some information about it.
I'm interested in energies for the incident e^{-} above 200MeV.
I think it has to do something with...
1. The statement, all variables and given/known data
I am studying the decay of the \eta-particle. Povh et Al, 'Particles and nuclei' say that a decay into 3 pions is not possible via the strong interaction. "For reasons of symmetry 3 pions (isospin equals 1) can not couple to zero isospin."...
Hi all,
I'm having trouble understanding the short lifetime on the neutral pion. I understand that in the residual strong interaction between nucleons, the range of the virtual pion is limited by Heisenberg's uncertainty relation for energy, which thus limits its lifetime. I don't...
How is it possible to have a pion that is made up of a linear combination of quarks? I mean, what are the physical constituents of the neutral pion? is it uubar or ddbar? Or does the linear combination mean that there is a 50 50 chance of a neutral pion being a made of uubar and ddbar?
I'm not sure whether this should go in this forum or the Advanced forum, but here goes.
Homework Statement
Given:
A pion+ decays into muon+ and neutrino,
\pi^+ \rightarrow \mu^+ + \nu
neutrino mass approaches zero, and
the pion is initially at rest.
Problem statement: Use...
I have one stupid question:
Is it true that the difference of proton and nucleon mass is due to the electromagnetic self-energy of the proton?
The same question about pi^0 and pi^- mass difference.
Consider this decay:
Pion+ -> muon+ + neutrino
It says that one can check the longitudinal polarization of the muon+ and this would confirm that the parity is not conserved. Can you explain what this means in simple terms?
The electromagnetic neutral pion decay is a three-point interaction: it decays into two virtual and charged Kaons or Protons, of which one then radiates a photon and then annihalates with the other to produce a second photon. (Obviously, a neutral particle cannot radiate photons directly)...
Hi first time user here.
I was hoping someone could please help me with the following question:
A moving neutral pion is observed to decay into 2 photons each with energy 80MeV, there being an angle 120deg between their trajectories.Calc
i)The total energy of the meson
ii)The momentum of...
Hi, i have a particle physics exam in 2 days and am confused on pion decay via the weak interaction, namely:
pi[-] ->muon + anti-muno neutrino
Thankyou
Ray Veldkamp