Z(4430)

Z(4430)
Classification Exotic meson
Composition ccdu

Z(4430) is a mesonic resonance discovered by the Belle experiment.[1][2] It has a mass of 4430 MeV/c2. This resonance has been confirmed by the LHCb experiment with a significance of at least 13.9 σ.[3] The particle is charged and is thought to have a quark content of ccdu,[3] making it a tetraquark candidate. It has the spin-parity quantum numbers JP = 1+.

The particle joins the X(3872), Zc(3900) and Y(4140) as confirmed exotic hadron candidate resonances, although it is the first to be confirmed with such high statistical significance.[4][5]

References

  1. Choi, S.-K.; et al. (Belle Collaboration) (2007). "Observation of a resonance-like structure in the π±Ψ mass distribution in exclusive BKπ±Ψ decays". Physical Review Letters 100 (14). arXiv:0708.1790. Bibcode:2008PhRvL.100n2001C. doi:10.1103/PhysRevLett.100.142001.
  2. "Belle Discovers a New Type of Meson" (Press release). KEK. 2007. Retrieved 2009-06-20.
  3. 3.0 3.1 LHCb collaboration (2014). "Observation of the resonant character of the Z(4430)− state". v1. arXiv:1404.1903.
  4. Cian O'Luanaigh (9 April 2014). "LHCb confirms existence of exotic hadrons". CERN.
  5. "Unambiguous observation of an exotic particle which cannot be classified within the traditional quark model". European Organization for Nuclear Research. 9 April 2014.

External links