Primordial Black Holes and Cosmological Phase Transitions Report ...

PBHs and Cosmological Phase Transitions 40
Table 7: The fundamental mesons and their most common excited states. For each meson and antimeson it is indicated
the symbol, the quark content, the electric charge e, the spin s, the mean lifetime t and, whenever possible, the two most
probable decaying reactions with corresponding probabilities (for more data on these and other mesons consult the PDG –
http://pdg.lbl.gov/2007/listings/contents listings.html, Yao et al., 2006).
Name Meson Antimeson quark content e s m(MeV) t(s) Most probable decaying Second most probable
symbol symbol reaction decaying reaction
pion π + π− u ¯ d ūd ±1 0 139.57 2.6 × 10−8 π ± → µ ± + νµ 99.99%
neutral pion π0 √
(self) uū − dd¯ −17 / 2 – 0 0 134.98 8.4 × 10 π0 → γ + γ 98.80%
d¯s − s ¯ d / √ 2 – 0 0 497.648 8.953 × 10 −11 K 0 S → π+ + π − 69.2% K 0 S → π0 + π 0 30.7%
charged kaon K + K− u¯s ūs ±1 0 493.68 1.24 × 10−8 K ± → µ ± + νµ 63.4% K ± → π ± + π0 21%
neutral kaon K0 ¯ K0 d¯s ds ¯ 0 0 497.648 – – – –
K–Short K0 S (self)
K–Long K0 √
L (self) d¯s + sd¯ −8 / 2 – 0 0 497.648 5.116 × 10 K0 L → π± + e∓ + νe 40.6% K0 L → π± + µ ∓ + νµ 27%
charged rho ρ + ρ− u ¯ d ūd ±1 1 775.4 – ρ ± → π ± + π0 ≈ 100%
neutral rho ρ0 √
(self) uū − dd¯ 0 + − 0 0 / 2 – 0 1 775.49 – ρ → π + π + γ – ρ → π + γ –
uū + d ¯ d / √ 2 – 0 1 782.65 – ω → π + + π − + π 0 89.1% ω → π 0 + γ 8.9%
omega ω (self)
phi ϕ (self) s¯s – 0 1 1019.46 – ϕ → K + + K− 49.3% ϕ → K0 S + K0 √ L 34.0%
eta η (self) uū + dd¯ 0 0 0 − 2s¯s / 6 – 0 0 547.51 – η → γ + γ 39.4% η → π + π + π 32.5%
eta prime η ′ √
(self) uū + dd ¯ ′ + + ′ 0 + − + s¯s / 6 – 0 0 957.78 – η → π + π + η 44.5% η → ρ + γ +(π + π + γ) 29.4%
charged D D + D− c ¯ d ¯cd ±1 0 1869.62 1.04 × 10−12 D ± → K0 + ... + ¯ K0 + ... 61% D ± → K ± + ... 27%
neutral D D0 ¯ D0 cū ¯cu 0 0 1864.84 4.1 × 10−13 strange D D + s D− s c¯s ¯cs ±1 0 1968.2 5.0 × 10−13 D ± s → K0 + ... + ¯ K0 + ... 39% D ± s → K± + ... 13%
J/Psi J/ψ (self) c¯c – 0 1 396.92 – J/ψ → hadrons 88% J/ψ → e + + e− 6%
charged B B + B − u ¯ b ūb ±1 0 5297.0 1.638 × 10 −12 B ± → l ± + νl + ... 10.9%
strange B B0 s
charmed B B + c B− c c¯b ¯cb ±1 0 6286 4.6 × 10−11 B ± c → J/ψ + l ± + νl – B ± c → J/ψ + π ± –
neutral B B0 ¯ B0 d¯b db ¯ −12 0 0 5279.5 1.530 × 10 B0 → l + + νl + ... 10.4%
¯B 0 s s¯b ¯sb 0 0 5367.5 1.466 × 10−12 B0 s → D− s + ... 94%
Upsilon Υ (self) b ¯ b – 0 1 9460.3 – Υ → τ + + τ − 2.6% Υ → µ + + µ − 2.5%