Physics:D meson

From HandWiki
D meson
StatisticsBosonic
InteractionsStrong, weak, electromagnetic, gravitational
SymbolD+, D, D0, D0, D+s, Ds
DiscoveredSLAC (1976)
Spin0
Charm+1
Parity−1

The D mesons are the lightest particle containing charm quarks. They are often studied to gain knowledge on the weak interaction.[1] The strange D mesons (Ds) were called "F mesons" prior to 1986.[2]

Overview

The D mesons were discovered in 1976 by the Mark I detector at the Stanford Linear Accelerator Center.[3]

Since the D mesons are the lightest mesons containing a single charm quark (or antiquark), they must change the charm (anti)quark into an (anti)quark of another type to decay. Such transitions involve a change of the internal charm quantum number, and can take place only via the weak interaction. In D mesons, the charm quark preferentially changes into a strange quark via an exchange of a W particle, therefore the D meson preferentially decays into kaons (Kaon) and pions ( Pion ).[1]

List of D mesons

D mesons
Particle
name
Particle
symbol
Antiparticle
symbol
Quark
content[4]
Rest mass (MeV/c2) I JP S C B' Mean lifetime (s) Commonly decays to
(>5% of decays)
Charged D meson[5] D+ D Charm quarkDown antiquark 1869.62±0.20 1/2 0 0 +1 0 (1.040±0.007)×10−12 [6]
Neutral D meson[7] D0 D0 Charm quarkup antiquark 1864.84±0.17 1/2 0 0 +1 0 (4.101±0.015)×10−13 [8]
Strange D meson[9] D+s Ds Charm quarkstrange antiquark 1968.47±0.33 0 0 +1 +1 0 -13.1 (5.00±0.07)×10−13


[10]
Excited charged D meson[11] D∗+(2010) D∗−(2010) Charm quarkDown antiquark 2010.27±0.17 1/2 1 0 +1 0 (6.9±1.9)×10−21 D0 + Pion+ or
D+ + Pion0
Excited neutral D meson[12] D∗0(2007) D∗0(2007) Charm quarkup antiquark 2006.97±0.19 1/2 1 0 +1 0 >3.1×10−22 D0 + Pion0 or
D0 + Photon

^ PDG reports the resonance width [math]\displaystyle{ ~\left(\Gamma\right)~. }[/math] Here the conversion [math]\displaystyle{ \; \tau = \frac{\hbar}{\Gamma} \; }[/math] is given instead.

DD oscillations

In 2021 it was confirmed with a significance of more than seven standard deviations, that the neutral D0 meson spontaneously transforms into its own antiparticle and back. This phenomenon is called flavor oscillation and was prior known to exist in the neutral B mesons. [13]

See also


References

  1. 1.0 1.1 Nave, G., ed (2016). "D meson". Georgia State University. http://hyperphysics.phy-astr.gsu.edu/hbase/particles/dmeson.html. 
  2. Wohl, C.G. (1984). "Review of Particle Physics". Reviews of Modern Physics (Particle Data Group) 56 (2, Part II). doi:10.1103/RevModPhys.56.S1. https://cds.cern.ch/record/153729/files/RevModPhys.56.S1.pdf. 
  3. Kudryavtsev, Vitaly A.. "Charmed mesons". University of Sheffield. http://www.kudryavtsev.staff.shef.ac.uk/phy466/charmed-mesons_files/charmed-mesons.ppt. 
  4. Amsler, C. (2008). "Quark Model". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/reviews/quarkmodrpp.pdf. 
  5. Amsler, C. (2008). "D±". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/s031.pdf. 
  6. Amsler, C. (2008). "D±". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/s031.pdf. 
  7. Amsler, C. (2008). "D0". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/s032.pdf. 
  8. Amsler, C. (2008). "D0". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/s032.pdf. 
  9. Nakamura, N. (2010). "D±s". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2010/listings/rpp2010-list-Ds-plus-minus.pdf. 
  10. Nakamura, N. (2010). "D+s". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2010/listings/rpp2010-list-Ds-plus-minus.pdf. 
  11. Amsler, C. (2008). "D∗±". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/m062.pdf. 
  12. Amsler, C. (2008). "D∗0 (2007)". Lawrence Berkeley Laboratory. http://pdg.lbl.gov/2008/listings/m061.pdf. 
  13. Aaij, R. (14 September 2021). "Observation of the mass difference between neutral charm-meson eigenstates". Physical Review Letters 127 (11): 111801. doi:10.1103/PhysRevLett.127.111801. 2106.03744. PMID 34558945. Bibcode2021PhRvL.127k1801A. https://arxiv.org/abs/2106.03744. "Published 2021 in Physical Review Letters 127, 111801. Report numbers: LHCb-PAPER-2021-009, CERN-EP-2021-099.".