Search results
Results From The WOW.Com Content Network
The weak interaction has a very short effective range (around 10 −17 to 10 −16 m (0.01 to 0.1 fm)). [b] [14] [13] At distances around 10 −18 meters (0.001 fm), the weak interaction has an intensity of a similar magnitude to the electromagnetic force, but this starts to decrease exponentially with increasing distance.
The mechanism relies on the unitarity of the charged weak current flavor mixing matrix, which enters in the two vertices of a one-loop box diagram involving W boson exchanges. Even though Z 0 boson exchanges are flavor-neutral (i.e. prohibit FCNC), the box diagram induces FCNC, but at a very small level.
Mesons named with the letter "f" are scalar mesons (as opposed to a pseudo-scalar meson), and mesons named with the letter "a" are axial-vector mesons (as opposed to an ordinary vector meson) a.k.a. an isoscalar vector meson, while the letters "b" and "h" refer to axial-vector mesons with positive parity, negative C-parity, and quantum numbers I G of 1 + and 0 − respectively.
) is a process that involves both weak and strong interactions. Weak interactions : The strange antiquark (s) of the kaon transmutes into an up antiquark (u) by the emission of a W + boson; the W + boson subsequently decays into a down antiquark (d) and an up quark (u). Strong interactions: An up quark (u) emits a gluon (g
Consequently, the lightest particles containing a strange quark cannot decay by the strong interaction, and must instead decay via the much slower weak interaction. In most cases these decays change the value of the strangeness by one unit. This doesn't necessarily hold in second-order weak reactions, however, where there are mixes of K 0 and K ...
When they decayed through the weak interactions, they had lifetimes of around 10 −10 seconds. While studying these decays, Murray Gell-Mann (in 1953) [4] [5] and Kazuhiko Nishijima (in 1955) [6] developed the concept of strangeness (which Nishijima called eta-charge, after the eta meson (η)) to explain the "strangeness" of the longer-lived ...
The weak interaction is responsible for various forms of particle decay, such as beta decay. It is weak and short-range, due to the fact that the weak mediating particles, W and Z bosons, have mass. W bosons have electric charge and mediate interactions that change the particle type (referred to as flavor) and charge.
Examples of mesons include the pion, kaon, and the J/ψ. In quantum hadrodynamics , mesons mediate the residual strong force between nucleons. At one time or another, positive signatures have been reported for all of the following exotic mesons but their existences have yet to be confirmed.