D meson

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 the "F mesons" prior to 1986.

D meson
Composition
D+
:
c

d


D−
:
d

c


D0
:
c

u


D0
:
u

c


D+
s:
c

s


D−
s:
s

c

StatisticsBosonic
InteractionsStrong, weak, electromagnetic, gravitational
Symbol
D+
,
D−
,
D0
,
D0
,
D+
s,
D−
s
Mass
D±
: 1869.62±0.20 MeV/c2

D0
/
D0
: 1864.84±0.17 MeV/c2

D±
s: 1968.47±0.33 MeV/c2
Electric charge
D±
,
D±
s: ±1 e

D0
,
D0
: 0 e

Overview

The D mesons were discovered in 1976 by the Mark I detector at the Stanford Linear Accelerator Center.[2]

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 (
K
) and pions (
π
).[1]

List of D mesons
D mesons
Particle
name		 Particle
symbol		 Antiparticle
symbol		 Quark
content[3]		 Rest mass (MeV/c2) IG JPC S C B' Mean lifetime (s) Commonly decays to
(>5% of decays)
D meson[4]
D+
D−
c

d
 1869.62±0.20 1/2 0− 0 +1 0 (1.040±0.007)×10−12 See
D+
 decay modes
D meson[5]
D0
D0
c

u
 1864.84±0.17 1/2 0− 0 +1 0 (4.101±0.015)×10−13 See
D0
 decay modes
Strange D meson[6]
D+
s
D−
s
c

s
 1968.47±0.33 0 0− +1 +1 0 (5.00±0.07)×10−13 See
D+
s decay modes
Excited D meson[7]
D∗+
(2010)
D∗−
(2010)
c

d
 2010.27±0.17 1/2 1− 0 +1 0 (6.9±1.9)×10−21[a]
D0
 +
π+
 or

D+
 +
π0
Excited D meson[8]
D∗0
(2007)
D∗0
(2007)
c

u
 2006.97±0.19 1/2 1− 0 +1 0 >3.1×10−22[a]
D0
 +
π0
 or

D0
 +
γ

[a] ^ PDG reports the resonance width (Γ). Here the conversion τ = ħ/Γ is given instead.

See also

References
  1. D Meson
  2. http://www.kudryavtsev.staff.shef.ac.uk/phy466/charmed-mesons_files/charmed-mesons.ppt%5B%5D
  3. C. Amsler et al.. (2008): Quark Model
  4. C. Amsler et al.. (2008): Particle listings –
    D±
  5. C. Amsler et al.. (2008): Particle listings –
    D0
  6. N. Nakamura et al.. (2010): Particle listings –
    D±
    s
  7. C. Amsler et al.. (2008): Particle listings –
    D∗±
    (2010)
  8. C. Amsler et al.. (2008): Particle listings –
    D∗0
    (2007)


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