mesons


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Related to mesons: Leptons, Quarks, Baryons

mesons

(mee -zon, -son, mess -on, mez -on) See elementary particles.
References in periodicals archive ?
That match, with only a 1-in-100,000 chance of being caused by a statistical error, virtually eliminates any possibility that B-sub-s meson decay is related to interaction with particles predicted by dark matter theories, as some physicists have suspected.
However the natural scale for the size of parity-odd amplitudes, set by the ratio of the amplitudes for W and Z exchange to those for meson exchange between nucleons, is extremely small ([approximately equal to][10.sup.-7]), and therein lies the experimental challenge.
In addition to B mesons, the vector ground states of b[bar.q] system, [B.sup.*] mesons, with quantum number of [n.sup.2s+1][L.sub.J] = [1.sup.3][S.sub.1] and [J.sup.P] = [1.sup.-] [66-69], also can decay through the b [right arrow] (u, c)l[[bar.[nu]].sub.l] transitions at quark-level.
[Z.sub.c](3900) could be a single entity of four quarks, Skwarnicki says, but it could also be a coupling of two mesons, analogous to two atoms linking up to form a molecule.
Mesons, on the other hand, are made of just two - specifically one quark and one antimatter quark.
Based on Table 3, Figure 3 shows the distribution of mesons, but Figure 4 shows the distribution of baryons, mesons, leptons and gauge bosons over the 1/4 logarithmic S-intervals in the range of 0 to 12 logarithmic units.
Theoretical descriptions of the weak nucleon-nucleon interaction are traditionally based on an effective meson exchange model in which the coupling constants for parity violating [pi], [rho], and [omega] meson exchanges set the scale for weak interaction effects and are uncertain to within factors of 2 to 3 on theoretical grounds [1].
Mesons, nucleons (protons and neutrons), and hyperons were all grouped together as hadrons, from a Greek word meaning "thick" or "strong," since they were all subject to the strong interaction.
In relativistic heavy ion collisions, the production of [[eta].sub.Q] mesons by the gluon-gluon (g-g) processes from the initial parton interaction can be divided into three processes: direct g-g processes, semielastic resolved photoproduction, and inelastic resolved photoproduction processes.
Particles called B, mesons seemed to be disintegrating into a muon (a cousin of the electron) and an anti-muon more frequently than expected.
Papers are presented grouped into the main topics of structure function, vector mesons, electroweak and beyond the standard model, hadronic final states, heavy flavors, spin physics, and the future of DIS.
In order for the paper to be self-contained let's recall that the pionium is formed by a [[pi].sup.+] and [[pi].sup.-] mesons, the positronium is formed by an antielectron (positron) and an electron in a semi-stable arrangement, the protonium is formed by a proton and an antiproton also semi-stable, the antiprotonic helium is formed by an antiproton and electron together with the helium nucleus (semi-stable), and muonium is formed by a positive muon and an electron.