What happens when an electron and positron annihilate each other?
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.
What does the W boson decay to?
The W− boson subsequently decays into an electron and an electron antineutrino. In weak interactions, the total number of quarks minus the total number of antiquarks is the same both before and after the interaction. The number of leptons is also conserved.
What happens when electron and positron collide?
annihilation, in physics, reaction in which a particle and its antiparticle collide and disappear, releasing energy. The most common annihilation on Earth occurs between an electron and its antiparticle, a positron.
Can W bosons annihilate?
A few examples: a W+ boson and a W- boson can annihilate or exchange a photon (or Z boson) and produce another two W bosons (Figure 5 below); two W bosons can also go in and produce two photons, two Z bosons, or a photon and Z boson; in fact, two photons can go in and even produce two W bosons!
What happens when a positron collides with a proton?
Most likely, it bounces off. Same as if an electron hits a proton or a neutron. If it a positron is captured by a neutron, however, it would form a proton, emitting a neutrino to conserve lepton number. If a positron were to be captured by a proton, it would have to form a baryon with net +2 electric charge.
What happens when an electron and antielectron or positron meet?
When an electron and positron (antielectron) collide at high energy, they can annihilate to produce charm quarks which then produce D+ and D- mesons. Frame 3: The electron and positron have annihilated into a photon, or a Z particle, both of which may be virtual force carrier particles.
What are W particles?
W particle, one of two massive electrically charged subatomic particles that are thought to transmit the weak force—that is, the force that governs radioactive decay in certain kinds of atomic nuclei.
What is the range of the W − particle that is responsible for the weak interaction of a proton and a neutron?
The weak interaction has a very short effective range (around 10−17 to 10−16 m).
Why do mesons not annihilate?
In a particle such as a positive pi meson (also called a pion), one quark is an up quark, and the other, the anti-quark, is an anti-down-quark. So they are different particles, and they can’t annihilate.
Why don t protons and electrons annihilate?
Protons and electrons do not annihilate each other on contact because they are not each other’s opposite particles. They are entirely different from one another, and just happen to carry opposite electric charges.
What happens to the positron in beta decay?
Positron emission, beta plus decay, or β+ decay is a subtype of radioactive decay called beta decay, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino (νe). Positron emission is mediated by the weak force.
What is the electron–positron annihilation process?
The electron–positron annihilation process is the physical phenomenon relied on as the basis of positron emission tomography (PET) and positron annihilation spectroscopy (PAS).
What happens when an electron and positron collide with each other?
Electron–positron annihilation occurs when an electron (. e −. ) and a positron (. e +. , the electron’s antiparticle) collide. At low energies, the result of the collision is the annihilation of the electron and positron, and the creation of gamma ray photons:
Can an electron-positron pair produce a Higgs boson?
The electron-positron pair can produce directly a Higgs boson, but this process is very suppressed, because the coupling between the leptons and the Higgs is proportional to the tiny mass m e: On the other hand, the process e + e − → H Z is more likely to happen, because the coupling between H and Z is proportional to the W mass:
Can a heavier particle be produced from an electron and positron?
If either the electron or positron, or both, have appreciable kinetic energies, other heavier particles can also be produced (such as D mesons or B mesons ), since there is enough kinetic energy in the relative velocities to provide the rest energies of those particles.