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BARYONS (S = 0, I = 1/2) P, N+ = Uud; N, N0 = Udd

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Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update N BARYONS (S = 0, I = 1/2) p, N+ = uud; n, N0 = udd p P 1 1 + I (J ) = 2 ( 2 ) Mass m = 1.00727646688 ± 0.00000000009 u Mass m = 938.272081 ± 0.000006 MeV [a] −10 [b] mp − mp /mp < 7 × 10 , CL = 90% ¯ q q ¯ ¯ p /( p )=1¯ .00000000000 ± 0.00000000007 ¯ mp ¯ mp ¯q +¯ q /e < 7 × 10−10, CL = 90% [b] ¯ p p¯ ¯q + q ¯/e < 1 × 10−21 [c] ¯ p e ¯ Magnetic¯ ¯ moment µ = 2.7928473446 ± 0.0000000008 µN (µ + µ ) µ = (0.3 ± 0.8) × 10−6 p p ± p Electric dipole moment d < 0.021 × 10−23 e cm Electric polarizability α = (11.2 ± 0.4) × 10−4 fm3 Magnetic polarizability β = (2.5 ± 0.4) × 10−4 fm3 (S = 1.2) Charge radius, µp Lamb shift = 0.84087 ± 0.00039 fm [d] Charge radius, e p CODATA value = 0.8751 ± 0.0061 fm [d] Magnetic radius = 0.851 ± 0.026 fm [e] Mean life τ > 2.1 × 1029 years, CL = 90% [f ] (p → invisible mode) Mean life τ > 1031 to 1033 years [f ] (mode dependent) See the “Note on Nucleon Decay” in our 1994 edition (Phys. Rev. D50, 1173) for a short review. The “partial mean life” limits tabulated here are the limits on τ/Bi , where τ is the total mean life and Bi is the branching fraction for the mode in question. For N decays, p and n indicate proton and neutron partial lifetimes. Partial mean life p p DECAY MODES (1030 years) Confidence level (MeV/c) Antilepton + meson N → e+ π > 5300 (n), > 16000 (p) 90% 459 N → µ+ π > 3500 (n), > 7700 (p) 90% 453 N → ν π > 1100 (n), > 390 (p) 90% 459 p → e+ η > 10000 90% 309 p → µ+ η > 4700 90% 297 n → ν η > 158 90% 310 N → e+ ρ > 217 (n), > 720 (p) 90% 149 N → µ+ ρ > 228 (n), > 570 (p) 90% 113 HTTP://PDG.LBL.GOV Page1 Created: 5/22/2019 10:04 Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update N → ν ρ > 19 (n), > 162 (p) 90% 149 p → e+ ω > 1600 90% 143 p → µ+ ω > 2800 90% 105 n → ν ω > 108 90% 144 N → e+ K > 17 (n), > 1000 (p) 90% 339 N → µ+ K > 26 (n), > 1600 (p) 90% 329 N → ν K > 86 (n), > 5900 (p) 90% 339 0 n → ν K S > 260 90% 338 p → e+ K ∗(892)0 > 84 90% 45 N → ν K ∗(892) > 78 (n), > 51 (p) 90% 45 Antilepton + mesons p → e+ π+ π− > 82 90% 448 p → e+ π0 π0 > 147 90% 449 n → e+ π− π0 > 52 90% 449 p → µ+ π+ π− > 133 90% 425 p → µ+ π0 π0 > 101 90% 427 n → µ+ π− π0 > 74 90% 427 n → e+ K 0 π− > 18 90% 319 Lepton + meson n → e− π+ > 65 90% 459 n → µ− π+ > 49 90% 453 n → e− ρ+ > 62 90% 150 n → µ− ρ+ > 7 90% 115 n → e− K + > 32 90% 340 n → µ− K + > 57 90% 330 Lepton + mesons p → e− π+ π+ > 30 90% 448 n → e− π+ π0 > 29 90% 449 p → µ− π+ π+ > 17 90% 425 n → µ− π+ π0 > 34 90% 427 p → e− π+ K + > 75 90% 320 p → µ− π+ K + > 245 90% 279 Antilepton + photon(s) p → e+ γ > 670 90% 469 p → µ+ γ > 478 90% 463 n → ν γ > 550 90% 470 p → e+ γ γ > 100 90% 469 n → ν γ γ > 219 90% 470 Antilepton + single massless p → e+ X > 790 90% – p → µ+ X > 410 90% – HTTP://PDG.LBL.GOV Page2 Created: 5/22/2019 10:04 Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update Three (or more) leptons p → e+ e+ e− > 793 90% 469 p → e+ µ+ µ− > 359 90% 457 p → e+ ν ν > 170 90% 469 n → e+ e− ν > 257 90% 470 n → µ+ e− ν > 83 90% 464 n → µ+ µ− ν > 79 90% 458 p → µ+ e+ e− > 529 90% 463 p → µ+ µ+ µ− > 675 90% 439 p → µ+ ν ν > 220 90% 463 p → e− µ+ µ+ > 6 90% 457 n → 3ν > 5 × 10−4 90% 470 Inclusive modes N → e+ anything > 0.6 (n, p) 90% – N → µ+ anything > 12 (n, p) 90% – N → e+ π0 anything > 0.6 (n, p) 90% – ∆B = 2 dinucleon modes The following are lifetime limits per iron nucleus. p p → π+ π+ > 72.2 90% – p n → π+ π0 > 170 90% – nn → π+ π− > 0.7 90% – nn → π0 π0 > 404 90% – p p → K + K + > 170 90% – p p → e+ e+ > 5.8 90% – p p → e+ µ+ > 3.6 90% – p p → µ+ µ+ > 1.7 90% – p n → e+ ν > 260 90% – p n → µ+ ν > 200 90% – + p n → τ ντ > 29 90% – nn → νe νe > 1.4 90% – nn → νµ νµ > 1.4 90% – p n → invisible > 2.1 × 10−5 90% – p p → invisible > 5 × 10−5 90% – p DECAY MODES Partial mean life p p DECAY MODES (years) Confidence level (MeV/c) p → e− γ > 7 × 105 90% 469 p → µ− γ > 5 × 104 90% 463 p → e− π0 > 4 × 105 90% 459 p → µ− π0 > 5 × 104 90% 453 p → e− η > 2 × 104 90% 309 HTTP://PDG.LBL.GOV Page3 Created: 5/22/2019 10:04 Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update p → µ− η > 8 × 103 90% 297 − 0 p → e K S > 900 90% 337 − 0 3 p → µ K S > 4 × 10 90% 326 − 0 3 p → e K L > 9 × 10 90% 337 − 0 3 p → µ K L > 7 × 10 90% 326 p → e− γ γ > 2 × 104 90% 469 p → µ− γ γ > 2 × 104 90% 463 p → e− ω > 200 90% 143 P 1 1 + n I (J ) = 2 ( 2 ) Mass m = 1.0086649159 ± 0.0000000005 u Mass m = 939.565413 ± 0.000006 MeV [a] −5 (mn − mn )/ mn = (9 ± 6) × 10 mn − mp = 1.2933321 ± 0.0000005 MeV = 0.00138844919(45) u Mean life τ = 879.4 ± 0.6s (S=1.6) cτ = 2.6362 × 108 km Magnetic moment µ = −1.9130427 ± 0.0000005 µN Electric dipole moment d < 0.30 × 10−25 e cm, CL = 90% Mean-square charge radius r2 = −0.1161 ± 0.0022 ­ n® fm2 (S = 1.3) Magnetic radius r 2 = 0.864+0.009 fm q­ M ® −0.008 Electric polarizability α = (11.8 ± 1.1) × 10−4 fm3 Magnetic polarizability β = (3.7 ± 1.2) × 10−4 fm3 Charge q = (−0.2 ± 0.8) × 10−21 e Mean nn-oscillation time > 8.6 × 107 s, CL = 90% (free n) Mean nn-oscillation time > 2.7×108 s, CL = 90% [g] (bound n) Mean nn′-oscillation time > 448 s, CL = 90% [h] − [i] p e νe decay parameters λ ≡ gA / gV = −1.2732 ± 0.0023 (S = 2.4) A = −0.1187 ± 0.0010 (S = 2.6) B = 0.9807 ± 0.0030 C = −0.2377 ± 0.0026 a = −0.1059 ± 0.0028 ◦ [j] φAV = (180.017 ± 0.026) D = (−1.2 ± 2.0) × 10−4 [k] R = 0.004 ± 0.013 [k] HTTP://PDG.LBL.GOV Page4 Created: 5/22/2019 10:04 Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update p n DECAY MODES Fraction (Γi /Γ) Confidence level (MeV/c) − p e νe 100 % 1 − −3 p e νe γ [l] ( 9.2±0.7) × 10 1 −3 hydrogen-atom νe < 2.7 × 10 95% 1.19 Charge conservation (Q) violating mode −27 p νe νe Q < 8 × 10 68% 1 + P 1 1 + N(1440) 1/2 I (J ) = 2 ( 2 ) Re(pole position) = 1360 to 1380 (≈ 1370) MeV −2Im(pole position) = 160 to 190 (≈ 175) MeV Breit-Wigner mass = 1410 to 1470 (≈ 1440) MeV Breit-Wigner full width = 250 to 450 (≈ 350) MeV N(1440) DECAY MODES Fraction (Γi /Γ) p (MeV/c) N π 55–75 % 398 N η <1% † N π π 17–50 % 347 ∆(1232)π , P-wave 6–27 % 147 N σ 11–23 % – p γ , helicity=1/2 0.035–0.048 % 414 nγ , helicity=1/2 0.02–0.04 % 413 − P 1 3 − N(1520) 3/2 I (J ) = 2 ( 2 ) Re(pole position) = 1505 to 1515 (≈ 1510) MeV −2Im(pole position) = 105 to 120 (≈ 110) MeV Breit-Wigner mass = 1510 to 1520 (≈ 1515) MeV Breit-Wigner full width = 100 to 120 (≈ 110) MeV N(1520) DECAY MODES Fraction (Γi /Γ) p (MeV/c) N π 55–65 % 453 N η 0.07–0.09 % 142 N π π 25–35 % 410 ∆(1232)π 22–34 % 225 ∆(1232)π , S-wave 15–23 % 225 ∆(1232)π , D-wave 7–11 % 225 N σ < 2% – HTTP://PDG.LBL.GOV Page5 Created: 5/22/2019 10:04 Citation: M. Tanabashi et al. (Particle Data Group), Phys. Rev. D 98, 030001 (2018) and 2019 update p γ 0.31–0.52 % 467 p γ , helicity=1/2 0.01–0.02 % 467 p γ , helicity=3/2 0.30–0.50 % 467 nγ 0.30–0.53 % 466 nγ , helicity=1/2 0.04–0.10 % 466 nγ , helicity=3/2 0.25–0.45 % 466 − P 1 1 − N(1535) 1/2 I (J ) = 2 ( 2 ) Re(pole position) = 1500 to 1520 (≈ 1510) MeV −2Im(pole position) = 110 to 150 (≈ 130) MeV Breit-Wigner mass = 1515 to 1545 (≈ 1530) MeV Breit-Wigner full width = 125 to 175 (≈ 150) MeV N(1535) DECAY MODES Fraction (Γi /Γ) p (MeV/c) N π 32–52 % 464 N η 30–55 % 176 N π π 3–14 % 422 ∆(1232)π , D-wave 1–4 % 240 N σ 2–10 % – N(1440)π 5–12 % † p γ , helicity=1/2 0.15–0.30 % 477 nγ , helicity=1/2 0.01–0.25 % 477 − P 1 1 − N(1650) 1/2 I (J ) = 2 ( 2 ) Re(pole position) = 1640 to 1670 (≈ 1655) MeV −2Im(pole position) = 100 to 170 (≈ 135) MeV Breit-Wigner mass = 1635 to 1665 (≈ 1650) MeV Breit-Wigner full width = 100 to 150 (≈ 125) MeV N(1650) DECAY MODES Fraction (Γi /Γ) p (MeV/c) N π 50–70 % 547 N η 15–35 % 348 ΛK 5–15 % 169 N π π 8–36 % 514 ∆(1232)π , D-wave 6–18 % 345 N σ 2–18 % – N(1440)π 6–26 % 150 p γ , helicity=1/2 0.04–0.20 % 558 nγ , helicity=1/2 0.003–0.17 % 557 HTTP://PDG.LBL.GOV Page6 Created: 5/22/2019 10:04 Citation: M.
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  • Standard Model & Baryogenesis at 50 Years

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    Standard Model & Baryogenesis at 50 Years Rocky Kolb The University of Chicago The Standard Model and Baryogenesis at 50 Years 1967 For the universe to evolve from B = 0 to B ¹ 0, requires: 1. Baryon number violation 2. C and CP violation 3. Departure from thermal equilibrium The Standard Model and Baryogenesis at 50 Years 95% of the Mass/Energy of the Universe is Mysterious The Standard Model and Baryogenesis at 50 Years 95% of the Mass/Energy of the Universe is Mysterious Baryon Asymmetry Baryon Asymmetry Baryon Asymmetry The Standard Model and Baryogenesis at 50 Years 99.825% of the Mass/Energy of the Universe is Mysterious The Standard Model and Baryogenesis at 50 Years Ω 2 = 0.02230 ± 0.00014 CMB (Planck 2015): B h Increasing baryon component in baryon-photon fluid: • Reduces sound speed. −1 c 3 ρ c =+1 B S ρ 3 4 γ • Decreases size of sound horizon. η rdc()η = ηη′′ ( ) SS0 • Peaks moves to smaller angular scales (larger k, larger l). = π knrPEAKS S • Baryon loading increases compression peaks, lowers rarefaction peaks. Wayne Hu The Standard Model and Baryogenesis at 50 Years 0.021 ≤ Ω 2 ≤0.024 BBN (PDG 2016): B h Increasing baryon component in baryon-photon fluid: • Increases baryon-to-photon ratio η. • In NSE abundance of species proportional to η A−1. • D, 3He, 3H build up slightly earlier leading to more 4He. • Amount of D, 3He, 3H left unburnt decreases. Discrepancy is fake news The Standard Model and Baryogenesis at 50 Years = (0.861 ± 0.005) × 10 −10 Baryon Asymmetry: nB/s • Why is there an asymmetry between matter and antimatter? o Initial (anthropic?) conditions: .
  • Gauge and Higgs Bosons

    Gauge and Higgs Bosons

    Citation: P.A. Zyla et al. (Particle Data Group), Prog. Theor. Exp. Phys. 2020, 083C01 (2020) GAUGE AND HIGGS BOSONS PC γ (photon) I (J ) = 0,1(1 − −) Mass m < 1 10−18 eV × Charge q < 1 10−46 e (mixed charge) × Charge q < 1 10−35 e (single charge) × Mean life τ = Stable g I (JP ) = 0(1 ) or gluon − Mass m = 0 [a] SU(3) color octet graviton J = 2 Mass m < 6 10−32 eV × W J = 1 Charge = 1 e ± Mass m = 80.379 0.012 GeV ± W Z mass ratio = 0.88147 0.00013 ± m m = 10.809 0.012 GeV Z − W ± m + m = 0.029 0.028 GeV W − W − − ± Full width Γ = 2.085 0.042 GeV ± N = 15.70 0.35 π± ± N = 2.20 0.19 K ± ± N = 0.92 0.14 p ± N = 19.39 0.08 charged ± HTTP://PDG.LBL.GOV Page1 Created: 6/1/2020 08:28 Citation: P.A. Zyla et al. (Particle Data Group), Prog. Theor. Exp. Phys. 2020, 083C01 (2020) W − modes are charge conjugates of the modes below. p + W DECAY MODES Fraction (Γi /Γ) Confidence level (MeV/c) ℓ+ ν [b] (10.86± 0.09) % – e+ ν (10.71± 0.16) % 40189 µ+ ν (10.63± 0.15) % 40189 τ + ν (11.38± 0.21) % 40170 hadrons (67.41± 0.27) % – π+ γ < 7 × 10−6 95% 40189 + −3 Ds γ < 1.3 × 10 95% 40165 c X (33.3 ± 2.6 )% – +13 c s (31 −11 )% – invisible [c] ( 1.4 ± 2.9 )% – − π+ π+ π < 1.01 × 10−6 95% 40189 Z J = 1 Charge = 0 Mass m = 91.1876 0.0021 GeV [d] ± Full width Γ = 2.4952 0.0023 GeV ± Γℓ+ ℓ− = 83.984 0.086 MeV [b] ± Γinvisible = 499.0 1.5 MeV [e] ± Γhadrons = 1744.4 2.0 MeV ± Γµ+ µ−/Γe+ e− = 1.0001 0.0024 ± Γτ + τ −/Γe+ e− = 1.0020 0.0032 [f ] ± Average charged multiplicity N = 20.76 0.16 (S=2.1) charged ± Couplings to quarks and leptons ℓ g V = 0.03783 0.00041 u − ± g V = 0.266 0.034 d ±+0.04 g V = 0.38−0.05 ℓ − g A = 0.50123 0.00026 u − +0.028± g A = 0.519−0.033 g d = 0.527+0.040 A − −0.028 g νℓ = 0.5008 0.0008 ± g νe = 0.53 0.09 ± g νµ = 0.502 0.017 ± HTTP://PDG.LBL.GOV Page2 Created: 6/1/2020 08:28 Citation: P.A.
  • Baryon Spectrum of SU(4) Composite Higgs Theory with Two Distinct Fermion Representations

    Baryon Spectrum of SU(4) Composite Higgs Theory with Two Distinct Fermion Representations

    PHYSICAL REVIEW D 97, 114505 (2018) Baryon spectrum of SU(4) composite Higgs theory with two distinct fermion representations Venkitesh Ayyar,1 Thomas DeGrand,1 Daniel C. Hackett,1 William I. Jay,1 Ethan T. Neil,1,2,* Yigal Shamir,3 and Benjamin Svetitsky3 1Department of Physics, University of Colorado, Boulder, Colorado 80309, USA 2RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA 3Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel (Received 30 January 2018; published 8 June 2018) We use lattice simulations to compute the baryon spectrum of SU(4) lattice gauge theory coupled to dynamical fermions in the fundamental and two-index antisymmetric (sextet) representations simulta- neously. This model is closely related to a composite Higgs model in which the chimera baryon made up of fermions from both representations plays the role of a composite top-quark partner. The dependence of the baryon masses on each underlying fermion mass is found to be generally consistent with a quark-model description and large-Nc scaling. We combine our numerical results with experimental bounds on the scale of the new strong sector to estimate a lower bound on the mass of the top-quark partner. We discuss some theoretical uncertainties associated with this estimate. DOI: 10.1103/PhysRevD.97.114505 I. INTRODUCTION study of the baryon spectrum on a limited set of partially quenched lattices (i.e., with dynamical fundamental In this paper, we compute the baryon spectrum of SU(4) fermions but without dynamical sextet fermions) was gauge theory with simultaneous dynamical fermions in presented in Ref.