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When electron-positron annihilation occurs, we see a pairof gamma rays produced. The radiation is roughly, f = 2 (me) c2/ h = 2 x .9-30 x 916 x 1.533 = 2.4320 = 243 exaHertz. Use the link below to the related question for some discussion on electron-positron annihilation.

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What is the difference between a transmission electron microscope and transmission positron microscope?

The primary difference is that the transmission electron microscope has been invented and developed, and is in wide use. The transmission positron microscope is still a curiosity. Another difference is the obvious one. The transmission electron microscope uses electrons and the transmission positron microscope uses positrons. There are some serious technical issues that must be solved to gather a bunch of positrons, slow them down and then craft them into a beam. Just so you know. And then there's all that annoying gamma radiation that results from the annihilation of the positrons when they recombine with an electron. To have a sufficient quantity of positrons to create a usable beam would result in a high radiation load. The positrons are going to undergo mutual annihilation with an electron, remember? Two hot gamma rays will be exiting the annihilation event. Using the instrument will create some high levels of radiation, and might make it advisable to operate the device from across town.


What is the difference between bremsstrahlung and characteristic radiation?

Bremstrahlung is German for "braking radiation." It refers to radiation that is associated with the positive or negative acceleration of charged particles. The energy of the emitted photon equals the loss of kinetic energy of the particle. Characteristic radiation refers to groups of discrete wavelengths characteristic of the emitting element.


How can you find the frequency of gamma radiation when given the mega electron volts?

To find the frequency of gamma radiation from mega electron volts, you can use the equation E = h*f, where E is the energy in electron volts, h is Planck's constant, and f is the frequency. By converting mega electron volts to electron volts and rearranging the equation, you can solve for the frequency.


What is pair production?

Pair production is the transformation of electromagnetic energy into matter, into a particle and its antiparticle, usually an electron and a positron. Let's have a look at this situation. When a high energy gamma ray with a minimum energy of 1.022 MeV passes close to an atomic nucleus, a phenomenon called pair production can occur. In this event, the energy of the gamma ray is converted into mass. It's a play right out of Albert Einstein's quantum mechanical playbook. The electron and positron are opposites of each other, and the appearance of an elementary particle and its antiparticle must obey conservation laws. That's where the "assistance" of a nearby atomic nucleus comes in. The electron and positron will appear and come away from the event with some given kinetic energy, and will scatter and slow down as they move off. The positron, of course, will end up combining with an electron in a mutual annihilation event where the two particles have their mass entirely converted into energy. This will result in a pair of electromagnetic rays, or photons, leaving the annihilation event and moving in opposite directions.


What happens to an electron if it is given energy?

An electron emits energy in the form of an x-ray (a photon) when its energy level in the electron cloud decreases as a result of reduction in the excitation level of the cloud. This means that the position of the electron in the cloud changes to a lower level.

Related Questions

What is a fast moving electron that is given off as a nuclear radiation?

Beta radioactivity radiation.


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.


What is A fast moving electron that is given off as nuclear radiation?

Beta


What is the difference between a transmission electron microscope and transmission positron microscope?

The primary difference is that the transmission electron microscope has been invented and developed, and is in wide use. The transmission positron microscope is still a curiosity. Another difference is the obvious one. The transmission electron microscope uses electrons and the transmission positron microscope uses positrons. There are some serious technical issues that must be solved to gather a bunch of positrons, slow them down and then craft them into a beam. Just so you know. And then there's all that annoying gamma radiation that results from the annihilation of the positrons when they recombine with an electron. To have a sufficient quantity of positrons to create a usable beam would result in a high radiation load. The positrons are going to undergo mutual annihilation with an electron, remember? Two hot gamma rays will be exiting the annihilation event. Using the instrument will create some high levels of radiation, and might make it advisable to operate the device from across town.


What electron is given off by a nucleus?

In nuclear decay processes, electrons called beta particles are emitted by a nucleus. Beta particles can either be a beta-minus particle (an electron) or a beta-plus particle (a positron).


What type of radiation is given off in the nuclear reaction 14 6 C 14 7 N plus?

The type of radiation given off in this nuclear reaction is beta minus (β-) radiation. In this process, a neutron in the carbon-14 nucleus converts into a proton and an electron, which is emitted as beta radiation. This results in the transformation of carbon-14 into nitrogen-14.


What factor effects the intensity of light the color of light and the type of electromagnetic radiation that is given off by the electron?

Photoelectric effect


Is lepton part of an atom?

Lepton is the common name given to electron, positron, neutrino, antinuetrino, mu-meson [muon] etc. So an atom has these elementary particles within and come out in specific circumstances.


What are positrons and what medical imaging technique employs them?

Positronic Emission Tomography (PET Scanner) Positrons are the antiparticle to an Electron. Basically, a radioactive isotope is injected into the patient's blood, the isotope being unstable desires to reach stability, so a proton inside the nucleus is converted into a neutron by 'shedding' off a positron. After a few millimetres, the positron will encounter an electron. When these two particles collide they then 'annihilate' each other, a cocktail of photons are then given off in the form of gamma-rays. The sensors around the patient have photo sensitive plates that detect this gamma radiation, this then generates an electric current which via heavy computing is converted readily into an image.


What is the name given to particles with an opposite electrical charge to normal ones?

A particle with the same mass but with an opposite electrical charge of a particular known particle is called an Antiparticle. For example, the antiparticle of the electron is a positron, with equal mass but opposite charge.


What is the minimum energy to produce ionization?

The minium required energy of a photon that is involved in the creation of an electron-positron pair (which is pair production), is 1.022 MeV.An electron-positron pair has a given probability of being produced when a photon of the stated energy (or a higher energy) passes close the nucleus of an atom. Pair production does not happen "in the presence of a photon" but happens as a direct result of the the actual presence of a photon (having at least the stated energy) in the presence of an atomic nucleus. The presence of an atomic nucleus is necessary to insure conservation of the quantum mechanical characteristics of the event. Said another way, the high energy photon alone cannot spontaneously create the electron-positron pair in pair production. A link can be found below to related questions.


What is the difference between bremsstrahlung and characteristic radiation?

Bremstrahlung is German for "braking radiation." It refers to radiation that is associated with the positive or negative acceleration of charged particles. The energy of the emitted photon equals the loss of kinetic energy of the particle. Characteristic radiation refers to groups of discrete wavelengths characteristic of the emitting element.