D meson - Wiki slovník

D meson
Composition	; D+; : ; c; ; d; ; ; D−; : ; d; ; c; ; ; D0; : ; c; ; u; ; ; D0; : ; u; ; c; ; ; D+; s: ; c; ; s; ; ; D−; s: ; s; ; c; ;
Statistics	Bosonic
Family	Mesons
Interactions	Strong, weak, electromagnetic, gravitational
Symbol	; D+; , ; D−; , ; D0; , ; D0; , ; D+; s, ; D−; s
Antiparticle	; D+; : ; D−; ; ; D0; : ; D0; ; ; D+; s: ; D−; s;
Discovered	SLAC (1976)
Mass	; D±; : 1869.62±0.20 MeV/c2; ; D0; ,; D0; : 1864.84±0.17 MeV/c2; ; D±; s: 1968.47±0.33 MeV/c2;
Mean lifetime	; D±; : (1.040±0.007)×10−12; ; D0; ,; D0; : (4.101±0.015)×10−13; ; D±; s: (5.00±0.07)×10−13;
Electric charge	; D±; ,; D±; s: ±1 e; ; D0; ,; D0; : 0 e;
Spin	0
Strangeness	; D±; ,; D0; ,; D0; : 0; ; D±; s: ±1;
Charm	+1
Isospin	; D+; ,; D0; : +1/2; ; D−; ,; D0; : −1/2; ; D±; s: 0;
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 (D_s) 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 (
K
) and pions ( $π$ ).^[1]

List of D mesons

D mesons
Particle name	Particle symbol	Antiparticle symbol	Quark content^[4]	Rest mass (MeV/c²)	I	J^P	S	C	Mean lifetime (s)	Commonly decays to (>5% of decays)
Charged D meson^[5]	D⁺	D⁻	c d	1869.62±0.20	1/2	0⁻	0	+1	(1.040±0.007)×10⁻¹²	^[6]
Neutral D meson^[7]	D⁰	D⁰	c u	1864.84±0.17	1/2	0⁻	0	+1	(4.101±0.015)×10⁻¹³	^[8]
Strange D meson^[9]	D⁺ _s	D⁻ _s	c s	1968.47±0.33	0	0⁻	+1	+1	(5.00±0.07)×10⁻¹³	^[10]
Excited charged D meson^[11]	D^∗+ (2010)	D^∗− (2010)	c d	2010.27±0.17	1/2	1⁻	0	+1	(6.9±1.9)×10⁻²¹^{^‡}	D⁰ + π⁺ or D⁺ + π⁰
Excited neutral D meson^[12]	D^∗0 (2007)	D^∗0 (2007)	c u	2006.97±0.19	1/2	1⁻	0	+1	>3.1×10⁻²²^{^‡}	D⁰ + π⁰ or D⁰ + γ

‡ ^ PDG reports the resonance width $~\left(\Gamma \right)~.$ Here the conversion $\;\tau ={\frac {\hbar }{\Gamma }}\;$ is given instead.

D
–
D
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 K meson and B meson.^[13]

References

^ ^a ^b Nave, G., ed. (2016). "D meson". Department of Physics & Astronomy. HyperPhysics. Atlanta, GA: Georgia State University.
^ Wohl, C.G. (1984). "Review of Particle Physics" (PDF). Reviews of Modern Physics. Particle Data Group. 56 (2, Part II). doi:10.1103/RevModPhys.56.S1.
^ Kudryavtsev, Vitaly A. "Charmed mesons" (course files). Physics 466. University of Sheffield.^{[permanent dead link]}
^ Amsler, C.; et al. (Particle Data Group) (2008). "Quark Model" (PDF). Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D^±
" (PDF). Particle listings. Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D^±
" (PDF). Decay modes. Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D⁰
" (PDF). Particle listings. Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D⁰
" (PDF). Decay modes. Lawrence Berkeley Laboratory.
^ Nakamura, N.; et al. (Particle Data Group) (2010). "
D^±
_s" (PDF). Particle listings. Lawrence Berkeley Laboratory.
^ Nakamura, N.; et al. (Particle Data Group) (2010). "
D⁺
_s" (PDF). Decay modes. Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D^∗±
" (PDF). Decay modes. Lawrence Berkeley Laboratory.
^ Amsler, C.; et al. (Particle Data Group) (2008). "
D^∗0
(2007)" (PDF). Decay modes. Lawrence Berkeley Laboratory.
^ Aaij, R.; et al. (LHCb collaboration) (14 September 2021) . "Observation of the mass difference between neutral charm-meson eigenstates". Physical Review Letters. 127 (11): 111801. arXiv:2106.03744. Bibcode:2021PhRvL.127k1801A. doi:10.1103/PhysRevLett.127.111801. PMID 34558945. S2CID 235358523. 2106.03744. Published 2021 in Physical Review Letters 127, 111801. Report numbers: LHCb-PAPER-2021-009, CERN-EP-2021-099.

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[autogenerated1-1] Nave, G., ed. (2016). "D meson". Department of Physics & Astronomy. HyperPhysics. Atlanta, GA: Georgia State University.

[2] Wohl, C.G. (1984). "Review of Particle Physics" (PDF). Reviews of Modern Physics. Particle Data Group. 56 (2, Part II). doi:10.1103/RevModPhys.56.S1.

[3] Kudryavtsev, Vitaly A. "Charmed mesons" (course files). Physics 466. University of Sheffield.^{[permanent dead link]}

[PDGQuarkmodel-4] Amsler, C.; et al. (Particle Data Group) (2008). "Quark Model" (PDF). Lawrence Berkeley Laboratory.

[PDGD+-5] Amsler, C.; et al. (Particle Data Group) (2008). "
D^±
" (PDF). Particle listings. Lawrence Berkeley Laboratory.

[6] Amsler, C.; et al. (Particle Data Group) (2008). "
D^±
" (PDF). Decay modes. Lawrence Berkeley Laboratory.

[PDGD0-7] Amsler, C.; et al. (Particle Data Group) (2008). "
D⁰
" (PDF). Particle listings. Lawrence Berkeley Laboratory.

[8] Amsler, C.; et al. (Particle Data Group) (2008). "
D⁰
" (PDF). Decay modes. Lawrence Berkeley Laboratory.

[PDGDs-9] Nakamura, N.; et al. (Particle Data Group) (2010). "
D^±
_s" (PDF). Particle listings. Lawrence Berkeley Laboratory.

[10] Nakamura, N.; et al. (Particle Data Group) (2010). "
D⁺
_s" (PDF). Decay modes. Lawrence Berkeley Laboratory.

[PDGD*+-11] Amsler, C.; et al. (Particle Data Group) (2008). "
D^∗±
" (PDF). Decay modes. Lawrence Berkeley Laboratory.

[PDGD*0-12] Amsler, C.; et al. (Particle Data Group) (2008). "
D^∗0
(2007)" (PDF). Decay modes. Lawrence Berkeley Laboratory.

[13] Aaij, R.; et al. (LHCb collaboration) (14 September 2021) . "Observation of the mass difference between neutral charm-meson eigenstates". Physical Review Letters. 127 (11): 111801. arXiv:2106.03744. Bibcode:2021PhRvL.127k1801A. doi:10.1103/PhysRevLett.127.111801. PMID 34558945. S2CID 235358523. 2106.03744. Published 2021 in Physical Review Letters 127, 111801. Report numbers: LHCb-PAPER-2021-009, CERN-EP-2021-099.

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‡

[12]

[13]

Composition	D⁺ : c d D⁻ : d c D⁰ : c u D⁰ : u c D⁺ _s: c s D⁻ _s: s c
Statistics	Bosonic
Family	Mesons
Interactions	Strong, weak, electromagnetic, gravitational
Symbol	D⁺ , D⁻ , D⁰ , D⁰ , D⁺ _s, D⁻ _s
Antiparticle	D⁺ : D⁻ D⁰ : D⁰ D⁺ _s: D⁻ _s
Discovered	SLAC (1976)
Mass	D^± : 1869.62±0.20 MeV/c² D⁰ , D⁰ : 1864.84±0.17 MeV/c² D^± _s: 1968.47±0.33 MeV/c²
Mean lifetime	D^± : (1.040±0.007)×10⁻¹² D⁰ , D⁰ : (4.101±0.015)×10⁻¹³ D^± _s: (5.00±0.07)×10⁻¹³
Electric charge	D^± , D^± _s: ±1 e D⁰ , D⁰ : 0 e
Spin	0
Strangeness	D^± , D⁰ , D⁰ : 0 D^± _s: ±1
Charm	+1
Isospin	D⁺ , D⁰ : +1/2 D⁻ , D⁰ : −1/2 D^± _s: 0
Parity	−1

Overview

List of D mesons

D–D oscillations

See also

References

D
–
D
oscillations