ω meson

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Omega meson (ω)

classification
Boson
Hadron
Meson
properties
electric charge neutral
Resting energy (782.65 ± 0.12)  MeV
Spin parity 1 -
Isospin 0
average lifespan 7.75 ± 0.07 × 10 −23  s
Decay width (8.49 ± 0.08)  MeV
Quark
composition
Antisymmetric superposition of Up - Anti-Up and Down - Anti-Down

The ω meson , also omega meson , is a meson that has spin  1 (vector meson ), is made up of up and down quarks , but does not belong to the ρ mesons . While ρ mesons namely balanced flavor - wave functions have ( isospin 1), the flavor wave function of the ω-meson antisymmetric (isospin 0).

description

The ω meson is in the singlet representation of the SU (2) flavor. This means that there is only one ω meson with the flavor wave function

.

The ω meson is therefore often referred to as an isoscalar particle, i.e. a scalar with isospin symmetry (isospin I = 0). Therefore the ω-meson cannot be regarded as the excitation of a pion (I = 1).

89% of the ω meson decays into three pions via the strong interaction and 8% via the electromagnetic interaction into a pion and a photon .

Experimental measurements

The ω meson has been proven in experiments since the 1960s.

See also

Individual evidence

  1. The information on the particle properties (info box) are, unless otherwise stated, taken from: J. Beringer et al. ( Particle Data Group ): 2013 Review of Particle Physics. In: Physical Review D . Vol. 86, 2012, 010001 and 2013 partial update for the 2014 edition. Particle Data Group, accessed May 22, 2018 .
  2. N. Nakamura et al . (2010): Particle listings - ω (PDF; 182 kB)
  3. R. Kraemer, L.Madansky, Mosley sea, et al : Meson Resonance production in the π + d interactions at 1:23 BeV / c . In: Phys. Rev. B . No. 136 , 1964, pp. 496-506 , doi : 10.1103 / PhysRev.136.B496 .