Electron positron. Medical search. Frequent questions

At low energies, the result of the collision is the annihilation of the electron and positron, and the creation of energetic photons: e− + e+ → γ + γ At high energies, other particles, such as B mesons or the W and Z bosons, can be created. (wikipedia.org)
In the most common case, two gamma photons are created, each with energy equal to the rest energy of the electron or positron (0.511 MeV). (wikipedia.org)
A three-dimensional (3D) positron annihilation spectroscopy system (3DPASS) capable of determining 3D electron-positron ( e − -e + ) momentum densities from measurements of deviations from co-linearity and energies of photons from e − -e + annihilation events was employed to examine the effects of O-atom defects in 6H SiC. (afit.edu)
It is presumed that TGF photons are emitted by electrons traveling at speeds very close to the speed of light that collide with the nuclei of atoms in the air and release their energy in the form of gamma rays ( bremsstrahlung [7] ). (wikipedia.org)
Recent research has shown that electron-electron ( Bremsstrahlung ) [13] leads first to an enrichment of high-energy electrons and subsequently enlarges the number of high-energy photons. (wikipedia.org)
The released positron combines with an electron and produces 2 photons whose paths are 180 ° apart. (msdmanuals.com)
Ring detector systems encircling the positron-emitting source simultaneously detect the 2 photons to localize the source and to produce color tomographic images of the area. (msdmanuals.com)
After travelling at most a few millimetres, a positron will collide with an electron, simultaneously releasing two gamma rays (photons) with an energy of 511 keV into opposite directions. (lu.se)

citation needed] The electron-positron annihilation process is the physical phenomenon relied on as the basis of positron emission tomography (PET) and positron annihilation spectroscopy (PAS). (wikipedia.org)
This paper aimed to review the literature regarding the application of positron emission tomography in head and neck cancer, including its impact in the diagnosis, image principles, radiotracers, positron emission tomography / computed tomography image fusion and other advantages. (bvsalud.org)
It could be observed that the use of positron emission tomography improves the diagnostic approach of the patients, especially when positron emission tomography is allied to computed tomography. (bvsalud.org)
As it provides physiological information, positron emission tomography also benefits the prognostic and reduces the morbidity related to the treatment of head and neck cancer. (bvsalud.org)

Electron Collisions with Molecules in the Gas Phase. (routledge.com)
One method involves sending a high-intensity beam of electrons or protons into a massive beam dump from which only weakly interacting particles created in the collisions are able to escape. (aps.org)

Since neutrinos also have a smaller mass than electrons, it is also possible - but exceedingly unlikely - for the annihilation to produce one or more neutrino-antineutrino pairs. (wikipedia.org)
The heaviest particle pairs yet produced by electron-positron annihilation in particle accelerators are W+ - W− pairs (mass 80.385 GeV/c2 × 2). (wikipedia.org)
I have used QMC to calculate the van der Waals interaction between pairs of thin, metallic wires and layers, modelled by 1D and 2D homogeneous electron gases. (lancs.ac.uk)

The same would be true for any other particles, which are as light, as long as they share at least one fundamental interaction with electrons and no conservation laws forbid it. (wikipedia.org)
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. (wikipedia.org)
In contrast to conventional ion-electron plasmas, electron-positron 'pair' plasmas consist of charged particles with identical mass. (mpg.de)
However, calculating the distribution and energies of electrons in materials-the electronic structure -is a nontrivial problem because of the need to simulate large numbers of strongly interacting particles. (lancs.ac.uk)
Because of the short pulse duration, the γ photon, electron-positron, and neutron sources could find applications in material science, nuclear physics, laboratory astrophysics, and as injectors in laser-based accelerators of charged particles. (zcu.cz)
An atom consists of one nucleus, made of protons and neutrons, and many smaller particles called electrons. (cdc.gov)

A positron is a positively charged particle with the same mass as an electron. (answers-learning.com)
An atom or molecule which has acquired electrical charge by either losing electrons (positively charged ion) or gaining electrons (negatively charged ion). (jrank.org)
A positively charged electron. (jrank.org)
uses compounds containing radionuclides that decay by releasing a positron (the positively charged antimatter equivalent of an electron). (msdmanuals.com)

A new frontier in laboratory physics: magnetized electron-positron plasmas. (mpg.de)
Plans for the creation and studies of electron-positron plasmas in a stellarator. (mpg.de)
Linear gyrokinetic studies with ORB5 en route to pair plasmas. (mpg.de)
Linear gyrokinetics of electron-positron plasmas in closed field-line systems. (mpg.de)
Microstability of Magnetically Confined Electron-Positron Plasmas. (mpg.de)
Electron-positron plasmas may be present in laboratory experiments and certain astrophysical environments. (ncu.edu.tw)
Due to the inertia symmetry there have been some debates about whether the nonlinear electrostatic solitons generated easily in electron-proton plasmas may develop in electron-positron plasmas. (ncu.edu.tw)
The coexistence of electrostatic solitons and electromagnetic Alfvén waves with significant magnetic field fluctuations in the same system is a unique feature of electron-positron plasmas and the unified theory behind the formation mechanisms is well addressed in the paper. (ncu.edu.tw)

The reverse reaction, electron-positron creation, is a form of pair production governed by two-photon physics. (wikipedia.org)
Kapusta, J 1984, ' Electron-positron pair production as a probe of chiral symmetry in a hot QCD plasma ', Physics Letters B , vol. 136, no. 3, pp. 201-203. (umn.edu)

High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes and may enable the observation of phenomena such as dark-matter particle annihilation or decay. (nih.gov)
In this study we show the formation of electrostatic solitons and electromagnetic Alfvén waves in extensive magnetized electron-positron plasma system generated by streaming instabilities based on electromagnetic particle simulations along with fluid theory analyses. (ncu.edu.tw)
The first subatomic particle that was discovered was the electron. (answers.com)
Then you have got the particle called as electron. (answers.com)
It fallows that you have got the particle with about the same mass of electron and with no charge. (answers.com)

Bremsstrahlung from the California Institute of Technology electron synchrotron was incident on a liquid deuterium target. (caltech.edu)

The radiotracer accumulates in the tissue to be studied, and its radionuclide decays by emission of a positron (anti-electron). (lu.se)

Metronidazole is heterocyclic nitro derivative in which the nitro group of metronidazole is reduced by an electron transport protein such as NADPH in an anaerobic micro-organism [6,7,12,13]. (who.int)

Most properties of solids and molecules are determined by the behaviour of the electrons that bind their atoms together. (lancs.ac.uk)
By collecting a statistically significant number of radioactive events, mathematical algorithms reconstruct a three-dimensional image that shows the distribution of the positron-emitting molecules in the brain. (lu.se)
The efficiency sential y uniform after whole-body izing (i.e. removing electrons from) in causing damage and subsequent exposure to being highly heteroge- atoms or molecules of the medium biological effects is related not only neous in the case of non-uniform to the amount of energy transferred being traversed. (who.int)

The first-order Coulomb-Born approximation has been applied to the study of positronium formation through K-shell electron capture in the collision of positron with multi-electron atomic targets. (epj.org)
The researchers did not detect a dark photon signature in their electron-positron collision data, allowing them to place new stricter limits on dark sector models, including ones trying to explain a possible discrepancy between the measured and predicted value of the anomalous magnetic moment of the muon. (aps.org)

The results reveal an ultra-short, ultra-relativistic collimated positron population, and their energy spectra, angular distribution, and temporal profile are found. (zcu.cz)
Large populations of energetic electrons can form by avalanche growth driven by electric fields , a phenomenon called relativistic runaway electron avalanche (RREA). (wikipedia.org)

A gamma photon with enough energy can produce an electron and a positron. (physicsnet.co.uk)

An exception to this rule can occur for tightly bound atomic electrons. (wikipedia.org)
The phenomenon takes place in plasma, the state of matter composed of free electrons and atomic nuclei, or ions, that makes up 99 percent of the visible universe. (phys.org)

Lead is chosen as the secondary high-Z target because of its high cross-section of the giant dipole resonance and electron-positron pair production. (zcu.cz)

The differential and total cross sections are computed for the impact of positron on helium, carbon, neon, sodium and argon atoms, with the formation of positronium in its ground state. (epj.org)
But whether fast reconnection can occur in partially ionized plasma-plasma that includes atoms as well as free electrons and ions-is not well understood. (phys.org)

These data will facilitate the interpretation of the results of positron annihilation experiments, in which positrons are injected into metals or semiconductors in order to learn about the type and concentration of defects that are present in the sample. (lancs.ac.uk)

Scientists have also detected energetic positrons and electrons produced by terrestrial gamma-ray flashes. (wikipedia.org)

The combined measurement of the cosmic-ray electron and positron energy spectra and fraction provide a unique tool to improve our understanding of the production, acceleration and propagation mechanism of cosmic rays. (infn.it)
We report on the positron to electron ratio in the cosmic radiation over more than one decade in energy from 0.85 to 14 GeV, using the NMSU-WiZard/CAPRICE balloon borne magnet spectrometer. (unityfvg.it)
From a total of 2756 well identified e(-) and 498 e(+) we are able to construct the positron fraction R = e(+) /(e(+) + e(-)) as a function of energy with small errors from 0.85 GeV to 14 GeV for the first time. (unityfvg.it)
The positron fraction in the upper energy bins are in agreement with the latest high energy measurements. (unityfvg.it)
In particular, I have calculated the immersion energy, annihilation rate and momentum density of the annihilation radiation as a function of the density of the electron gas. (lancs.ac.uk)
When an electron and positron collide, they annihilate to convert all their mass into energy. (answers-learning.com)
Since the mass of a positron is the same as the electron, the energy produced by one positron is the same that the energy produced by one electron, that is to say, 511 keV. (answers-learning.com)
By conservation of energy and momentum, we have 1.022 MeV of energy produced by the annihilation between a positron and an electron. (answers-learning.com)
The same amount of energy (3.08x10²⁹ eV) is produced by one mol of positrons (because the mass of a positron is equal to the mass of an electron). (answers-learning.com)
Again, by conservation of energy and momentum, the total energy produced by the annihilation of 1 mol of positrons and 1 mol of electrons is 6.16x10²⁹ eV. (answers-learning.com)
Low-Energy Electron Stimulated Reactions in Nanoscale Water Films and Water:DNA Interfaces. (routledge.com)

The APEX collaboration is focused on the creation of confined, low-temperature, long-lived, electron-positron plasma in the laboratory. (mpg.de)

Electron-positron annihilation occurs when an electron ( e− ) and a positron ( e+ , the electron's antiparticle) collide. (wikipedia.org)
According to our hypothesis, the conversion of electrons and positrons into each other occurs by replacing the charge motion vector with the opposite vector. (library.kg)
The only difference is that the conversion of positrons into electrons occurs when the potential difference "+ / 0" is applied to the bridge. (library.kg)

A precise measurement by AMS02 of the electron spectrum up to 700 GeV and of the positron spectrum and positron fraction in primary cosmic rays up 500 GeV will be presented. (infn.it)

Members of a group typically have similar properties and electron configurations in their outer shell. (rsc.org)

The potential difference, giving rise to the force of motion of the charges, is formed not between the plus and minus, but between the plus and zero potential (positron current) and between the minus and zero potential (electronic current). (library.kg)

The single-zeta Roothaan-Hartree-Fock wave functions are used to describe the electron initial bound states. (epj.org)

In addition, DC generators generate a positron current with right rotation, and generate electron current with left rotation. (library.kg)
Metronidazole, being electron-affinic, can accept an electron from neutral free radical centres to generate a reactive cation that binds to an anion such as hydroxyl (OH-), causing a permanent lesion. (who.int)

It then introduces new theoretical studies on the physicochemical and chemical stages that describe the behavior of electrons in liquid hydrocarbons and the high-LET radiolysis of liquid water. (routledge.com)

It is also used as a method of measuring the Fermi surface and band structure in metals by a technique called Angular Correlation of Electron Positron Annihilation Radiation. (wikipedia.org)

The positron for example has the same mass as an electron but it has a positive (+) charge whereas and electron has a negative (-) charge. (physicsnet.co.uk)
An electron has a mass of 9.109 x 10 kg. (answers-learning.com)

radon in Volume nism mediated by free electrons. (who.int)

The methods are stochastic, generating random sets of electron coordinates with the appropriate distribution. (lancs.ac.uk)

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