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Why is it that sometimes when a very high energy electron hits a target material a positron and two or more electrons come out of the event?
An electron at high energy entering into a scattering event will bring all that energy with it. All that energy will have to be "dealt with" in the outcome. One way that a big chunk of it can be "handled" is almost magical. A large portion of the energy can be transformed into an electron-positron pair. This event is called pair production. We usually see it when a high energy gamma ray causes it, but it can be one of the outcomes in an energetic electron collision. The production of this pair of particles is the direct result of the conversion of energy into matter, and it will carry off a lot of the energy in the event. The minimum energy need to create the pair is 1.022 MeV. The original electron is still "in one piece" after the event, so it may look like the single electron crashed into a target and two electrons and a positron came away. It was actually the original electron and that electron-positron pair. If the original electron ionized another electron (or more) in the target material (which is possible), they will come away as well. Certainly there are a number of possible outcomes in an energetic electron scattering event, but pair production is one of the possible outcomes, depending on the energies involved and the target material.
What else can I help you with?
What is the difference between a positron and an electron?
An electron is the carrier of the negative electrostatic force, and it has a charge of -1. Also, the electron, along with the proton and neutron, are the "basic building blocks" of atoms, and they make up the matter all around us. The positron, on the other hand, is an anti-electron - it's antimatter! And it is the antiparticle of the electron. It has a charge of +1, which is just the opposite of the electron's. The fact that the electron and positron are matter and anti-matter, and that they have a charge of -1 and +1 respectively are the major differences. A positron is an electron's anti-particle, and when the electron and positron come in contact with each other to combine, they annihilate each other in a process called electron-positron annihilation. There is a link below to that related question and to a couple of others.
Are laptons electrons?
I presume you mean lepton instead of lapton ;) In which case leptons are not electrons, but electrons are leptons. Leptons are a group of matter particles which do not feel the strong nuclear force and are believed to be elementary (i.e. they do not consist of smaller particles). They are: -Electron -Muon -Tau(on) -Electron neutrino -Muon neutrino -Tau neutrino and their associated anti particles (such as the anti-electron, commonly known as the positron).
Why don't positrons annihilate the electrons in the same atom when they're released?
The positron released from an atomic nucleus in positron emission (or beta plus decay) appears with high kinetic energy. It's moving very quickly, and because it is, it has an extremely low probability of actually interacting with that atom's electrons in mutual annihilation. That positron will undergo some scattering events to dump energy, and only then will the probability of it being able to actually "combine" with an electron increase to the point where it will actually do so.
Where do the electrons come from in proton proton chain reaction if hydrogen has only a proton in its atom?
when the 2 Hydrogen nuclei fuse, one of the protons is changed to a neutron via beta + decay, this produces an atom of Deuterium, a positron (beta + particle) and a neutrino. This positron will only travel a short distance before contacting an electron and annihilating each other to convert their masses and kinetic energies into the energy of the photons. The electron is most probably a free electron, as the high temperatures involved in Nuclear fusion would have provided enough energy to ionise electrons from their parent atom.
Why conversion of a photon to an electron positron pair is not possible in free space?
Because energy mass conservation will not be satisfied in free space, so that this process needs some material by which this conversion will be proceed.
What is the anti particles of electrons?
The antiparticle of the electron is, of course, the anti-electron. It is also known as a positron.
What is the anti-matter equivalent of an electron?
The anti-matter equivalent of an electron is a positron. Positrons have the same mass as electrons but have a positive charge. When a positron and an electron collide, they annihilate each other, releasing energy in the form of gamma rays.
Compare and contrast transmission electron microscopes and transmission positron microscpes?
Transmission electron microscopes use a beam of electrons to produce an image, while transmission positron microscopes use positrons. Both types of microscopes provide high resolution images, but while electron microscopes focus on the interactions of electrons with the sample, positron microscopes measure positron-electron annihilation events to create the image.
What are beta particles made up of?
Usually an electron, sometimes a positron.
What is the antiparticle of a positron?
The antiparticle of a positron is an electron. Both the positron and electron have the same mass but opposite charge, with the positron having a positive charge and the electron having a negative charge.
When are electrons destoryed?
The only interaction that would result in the destruction of an electron is when it collides with a positron.
What the difference between positive and negative electrons?
an electron always has a negative chargea positron is identical in all respects to an electron (sometimes it is called a "positive electron"), except it always has a positive charge and is antimatter (not matter)If an electron and a positron meet they will both cease to exist (annihilation) and gamma ray photons will be created.
Does positron have a negative charge?
A POSITron has a POSITive charge, hence the name. A positron is an anti-electron; since the electron has a negative charge, the positron has a positive charge.A POSITron has a POSITive charge, hence the name. A positron is an anti-electron; since the electron has a negative charge, the positron has a positive charge.A POSITron has a POSITive charge, hence the name. A positron is an anti-electron; since the electron has a negative charge, the positron has a positive charge.A POSITron has a POSITive charge, hence the name. A positron is an anti-electron; since the electron has a negative charge, the positron has a positive charge.
What electrons from negative and positive?
The electron is a negative charged particle.The positron is a positive charged particle.
What different between the electron capture and emission positron?
In one of them a positron is emitted. In the other an electron is captured. Since positrons are the antiparticles of electrons, it can be difficult in some cases to sort out which of these has actually occurred. Given the preponderance of electrons in normal matter, either way the net effect is going to be that an electron goes missing somewhere, either because it was "captured" or because it was annihilated when the positron ran into it.
Which of the following particles has the same mass as an electron but a positive charge and is sometimes emitted from the nucleus during radioactive decay?
The particle that has the same mass as an electron (9.11 x 10^-31 kg) but a positive charge and is sometimes emitted from the nucleus during radioactive decay is a positron. A positron is the antimatter counterpart to an electron and has a charge of +1.
What is the difference between a positron and electron and a nutrino?
A positron is like an electron in every way but charge, electrons having -1, positrons having +1. In other words, they're a positron is an electron's antiparticle. Neutrinos are chargeless, pointlike, nearly massless particles associated with electron and positron decays that exist in order to preserve the conservation of energy, momentum and angular momentum in these decay processes.
