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.
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 0 mesons. All in all, the amount of strangeness can change in a weak interaction reaction by +1, 0 or −1 (depending on the reaction).
It also explains why weak interactions that change strangeness by 2 (ΔS = 2 transitions) are suppressed, while those that change strangeness by 1 (ΔS = 1 transitions) are allowed, but only in charged current interactions.
Two different neutral K mesons, carrying different strangeness, can turn from one into another through the weak interactions, since these interactions do not conserve strangeness. The strange quark in the anti-K 0 turns into a down quark by successively absorbing two W-bosons of opposite charge. The down antiquark in the anti-
The Gell-Mann–Nishijima formula (sometimes known as the NNG formula) relates the baryon number B, the strangeness S, the isospin I 3 of quarks and hadrons to the electric charge Q. It was originally given by Kazuhiko Nishijima and Tadao Nakano in 1953, [ 1 ] and led to the proposal of strangeness as a concept, which Nishijima originally ...
The combination of the SU(2) gauge theory of the weak interaction, the electromagnetic interaction, and the Higgs mechanism is known as the Glashow–Weinberg–Salam model. Today it is widely accepted as one of the pillars of the Standard Model of particle physics, particularly given the 2012 discovery of the Higgs boson by the CMS and ATLAS ...
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.
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.