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]
D0
(2007)

D0
(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


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