What is Annihilation: Definition and 260 Discussions
In particle physics, annihilation is the process that occurs when a subatomic particle collides with its respective antiparticle to produce other particles, such as an electron colliding with a positron to produce two photons. The total energy and momentum of the initial pair are conserved in the process and distributed among a set of other particles in the final state. Antiparticles have exactly opposite additive quantum numbers from particles, so the sums of all quantum numbers of such an original pair are zero. Hence, any set of particles may be produced whose total quantum numbers are also zero as long as conservation of energy and conservation of momentum are obeyed.During a low-energy annihilation, photon production is favored, since these particles have no mass. However, high-energy particle colliders produce annihilations where a wide variety of exotic heavy particles are created.
The word "annihilation" takes use informally for the interaction of two particles that are not mutual antiparticles – not charge conjugate. Some quantum numbers may then not sum to zero in the initial state, but conserve with the same totals in the final state. An example is the "annihilation" of a high-energy electron antineutrino with an electron to produce a W−.
If the annihilating particles are composite, such as mesons or baryons, then several different particles are typically produced in the final state.
50.40.224.170 (talk)
If we could produce the highest order of Gamma Ray energy of a single photon
and bombarded an Atom with direct precision, Would the Atom be Annihilated?
If the Atom is Annihilated then would the release of Energy of the Atom be greater than the Single High Energy Gamma Photon?
Assume that...
Greetings--what is meant by "s-wave" or "p-wave" annihilation? I've been trying to figure out what this refers to by looking through the standard QM and QFT texts, but I keep missing this. Does anyone have a handy reference I can look up?
Thanks,
Flip
I read a book and there it is written something as following:
"By the lifetime of a virtual pair (e-e+) (that is given by the HUP) a virtual e- can remove with the distance s from the e+ that is given by: s=c*d(t) (d(t) from HUP)."
My question: How can they annihilate if they are away at a...
Why do proton and anti-proton annihilation can produce extra pions, in addition to the photons; whereas the electron and positron interaction only gives photons?
I have a question regarding particle-antiparticle annihilation, such as electron-positron, proton-antiproton, etc. Can the annihilation still occur if the two particles are in opposite spin eigenstates, i.e. if the pair has zero net spin?
A 5MeV electron undergoes annihilation with a positron that is at rest, producing two photons. One of the photons travels in the direction of the incident electron. Calculate the energy of each photon.
So the 5 MeV electron undergoes annihilation with a positron and from that 2 separate...
Well, I've been trying to figure out how to prove that when a positron and an electron annihilate and two photons are produced, the addition of their wavelengths equals
L1+L2=Lcompton(1-cos(theta)) where theta is the angle that separates both photons.
It's a relativity problem I guess. I...
At the colliders, positrons and electrons are accelerated at MeV, GeV levels on their way to making head-on collisions. Various Bosons can be produced. The most discussed type seems to be the two Gamma Photons (511 keV). Question #1: What happens to the XS energy of the positrons and...
I bumbed in such event in on book written in middle 80's.
Does anyone know anything of such phenomena? Has that theory been killed or is there any info available of it anywhere??
Oh joy... I'm writing an essay of neutrinos, and I am really lost.. :|
Oh, and another question... Any other...