Y(4140)
The Y(4140) particle is a previously unpredicted, electrically neutral particle that is about 4.4 times heavier than the proton. It was observed at Fermilab and announced on 17 March 2009.[1] This particle is extremely rare and was detected in only 20 of billions of collisions.[2]
Since it decays into J/ψ and φ mesons, it has been suggested that this particle is composed of charm quarks and charm antiquarks, possibly even a four quark combination.[3] The existence of the particle has been confirmed by members of the CMS collaboration at the Large Hadron Collider on November 14, 2012[4][5] and by the DZERO collaboration at the Tevatron on September 25, 2013.[6][7] The Belle experiment[8] and LHCb[9][10] have searched for this particle but found no evidence for its existence.
The Particle Data Group has renamed Y(4140) to follow naming conventions to X(4140).
References
- ↑ "Oddball Particle Surprises Physicists at Fermilab". redOrbit. 19 March 2009. Retrieved 2009-03-21.
- ↑ Handwerk, Brian (20 March 2009). "Strange Particle Created; May Rewrite How Matter's Made". National Geographic News. Retrieved 2009-03-21.
- ↑ Minard, Anne (18 March 2009). "New Particle Throws Monkeywrench in Particle Physics". Universe Today.
- ↑ Riesselmann, Kurt (December 4, 2012). "Experiment confirms existence of odd particle". Phys.Org.
- ↑ Hidalgo-Duquea, C., Nievesa, J., Pavón Valderrama, M. (November 29, 2012). "Heavy Quark Spin Symmetry and SU(3)-Flavour Partners of the X(3872)".
- ↑ Dorigo, Tommaso (September 26, 2013). "DZERO Confirms The Y(4140) And Its Excitation"
- ↑ D0 Collaboration (September 25, 2013). "Search for the X(4140) state in B+->J/psi phi K+ decays with the D0 detector"
- ↑ Shen et al., C. P. (2010). "Evidence for a New Resonance and Search for the Y(4140) in the γγ→ϕJ/ψ Process". Physical Review Letters 104: 112004. arXiv:0912.2383. Bibcode:2010PhRvL.104k2004S. doi:10.1103/PhysRevLett.104.112004.
- ↑ LHCb Collaboration (February 23, 2012). "Search for the X(4140) state in B+ to J/psi phi K+ decays"
- ↑ Dorigo, Tommaso (February 11, 2013). "The Mysterious Y(4140)"
Further reading
- Aaltonen, T.; et al. (2009). "Evidence for a Narrow Near-Threshold Structure in the J/ψφ Mass Spectrum B+ → J/ψφK+ Decays". Physical Review Letters 102: 242002. arXiv:0903.2229. Bibcode:2009PhRvL.102x2002A. doi:10.1103/PhysRevLett.102.242002.
- Xiang, Liu; Zhu, Shi-Lin (2009). "Y(4143) is probably a molecular partner of Y(3930)". Physical Review D 80: 017502. arXiv:0903.2529. Bibcode:2009PhRvD..80a7502L. doi:10.1103/PhysRevD.80.017502.
- Mahajan, Namit (2009). "Y(4140): Possible options". Physics Letters B 679 (3): 228–230. arXiv:0903.3107. Bibcode:2009PhLB..679..228M. doi:10.1016/j.physletb.2009.07.043.
External links
- Press release kit for the Y(4140). Contains images of decay modes and resonance data.