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Gauge Theories for Baryon Number

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Gauge Theories for Baryon Number Gauge Theories for Baryon Number. Michael Duerr International Workshop on Baryon and Lepton Number Violation 2017 (BLV 2017) Case Western Reserve University, 18 May 2017 Thanks to my collaborators. This talk is based on arXiv:1304.0576 [hep-ph], arXiv:1306.0568 [hep-ph], arXiv:1309.3970 [hep-ph], arXiv:1409.8165 [hep-ph], arXiv:1508.01425 [hep-ph], arXiv:1604.05319 [hep-ph], arXiv:1704.03811 [hep-ph] together with Pavel Fileviez Pérez (CWRU), Manfred Lindner (MPIK), Juri Smirnov (INFN and University Firenze), Mark B. Wise (Caltech) Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 2 The Standard Model of particle physics. > Standard Model gauge group: GSM = SU(3)C SU(2)L U(1)Y ⊗ ⊗ Field SU(3)C SU(2)L U(1)Y U(1)B U(1)L QL 3 2 1/6 1/3 0 R 3 1 2/3 1/3 0 dR 3 1 1/3 1/3 0 − ℓL 1 2 1/2 0 1 − eR 1 1 1 0 1 − H 1 2 1/2 0 0 Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 3 Baryon number. > Standard Model: > accidental global symmetry of the renormalizable couplings (broken by non-perturbative quantum effects) > stable p and no n–n¯ oscillations in the renormalizable SM > Generic GUT: > proton decay due to new gauge interactions > if quarks and leptons in the same multiplet one cannot define baryon number ! > What do we know about violation of B? [Figure: Viren, arXiv:hep-ex/9903029] > Baryon asymmetry of the Universe: γ π 0 P 10 e+ (nB nB¯)/nγ 10− − ∼ γ > Proton decay( ΔB = 1, ΔL = odd): 32 34 τp 10 − years ≥ Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 4 Side remark: lepton number. > Lepton number L conserved at the renormalizable level in the Standard Model as well > What do we know about violation of L? >ν oscillation experiments: ΔLe = 0, ΔLμ = 0, ΔLτ = 0 6 6 6 > ΔL = 2: Majorana neutrino masses (test with 0νββ) [Figure: Mohapatra et al., arXiv:hep-ph/0412099] Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 5 The desert of particle physics. c6 QQQL 2 ΛB [Weinberg, PRL 43 (1979) 1566] Low scale High scale Electroweak scale e.g. GUT scale 2 (Λ 1015 GeV) (ΛEW 10 GeV) ¦ ∼ [Figure: Wikipedia] Energy Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 6 The desert of particle physics. c6 QQQL 2 ΛB [Weinberg, PRL 43 (1979) 1566] Low scale High scale Electroweak scale e.g. GUT scale 2 (Λ 1015 GeV) (ΛEW 10 GeV) ¦ ∼ [Figure: Wikipedia] Energy Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 6 The desert of particle physics. c5 LLHH ΛL c6 QQQL 2 ΛB [Weinberg, PRL 43 (1979) 1566] Low scale High scale Electroweak scale e.g. GUT scale 2 (Λ 1015 GeV) (ΛEW 10 GeV) ¦ ∼ [Figure: Wikipedia] Energy Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 6 The desert of particle physics. c5 LLHH ΛL c6 QQQL 2 ΛB [Weinberg, PRL 43 (1979) 1566] Low scale High scale Electroweak scale e.g. GUT scale 2 (Λ 1015 GeV) (ΛEW 10 GeV) ¦ ∼ [Figure: Wikipedia] Energy Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 6 The desert of particle physics. c5 LLHH ΛL c6 QQQL 2 ΛB [Weinberg, PRL 43 (1979) 1566] Low scale High scale Electroweak scale e.g. GUT scale 2 (Λ 1015 GeV) (ΛEW 10 GeV) ¦ ∼ [Figure: Wikipedia] Energy Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 6 The Standard Model of particle physics. > Standard Model gauge group: GSM = SU(3)C SU(2)L U(1)Y ⊗ ⊗ Field SU(3)C SU(2)L U(1)Y U(1)B U(1)L QL 3 2 1/6 1/3 0 R 3 1 2/3 1/3 0 dR 3 1 1/3 1/3 0 − ℓL 1 2 1/2 0 1 − eR 1 1 1 0 1 − H 1 2 1/2 0 0 Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 7 The Standard Model of particle physics. > Extension of the SM gauge group: SU(3)C SU(2)L U(1)Y U(1)B U(1)L ⊗ ⊗ ⊗ ⊗ Field SU(3)C SU(2)L U(1)Y U(1)B U(1)L QL 3 2 1/6 1/3 0 R 3 1 2/3 1/3 0 dR 3 1 1/3 1/3 0 − ℓL 1 2 1/2 0 1 − eR 1 1 1 0 1 − H 1 2 1/2 0 0 Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 7 The Standard Model of particle physics. > Extension of the SM gauge group: SU(3)C SU(2)L U(1)Y U(1)B U(1)L ⊗ ⊗ ⊗ ⊗ Field SU(3)C SU(2)L U(1)Y U(1)B U(1)L Gauge theories for B (and L) QL 3 2 1/6 1/3 0 How to define a realistic theory R 3 1 2/3 1/3 0 where B (and L) are local gauge dR 3 1 1/3 1/3 0 symmetries that can− be broken at ℓL 1the low 2 (TeV) scale?1/2 0 1 − eR 1 1 1 0 1 − H 1 2 1/2 0 0 Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 7 Some history. Phys. Rev. 98, 1501 (1955) > heavy particle (= neutrons and protons) gauge transformation: α α ψN e ψN, ψP e ψP ! ! 45 > massless vector boson: gauge coupling must be tiny (αB ® 10− ) Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 8 Some history. Phys. Rev. D 8, 1844 (1973) > Use the Higgs mechanism to break B! Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 9 Some history. > Early discussions of gauging B (and L): anomaly cancellation, introduction of new fermions, properties of the gauge boson . > S. Rajpoot, Int. J. Theor. Phys. 27, 689 (1988) > R. Foot, G. C. Joshi, H. Lew, PRD 40, 2487 (1989) > C. D. Carone, H. Murayama, PRD 52, 484 (1995) > H. Georgi, S. L. Glashow, PLB 387, 341 (1996) > First realistic model (sequential/mirror family with B = 1) ± > P. Fileviez Pérez, M. B. Wise, PRD 82, 011901 (2010) Ruled out: new chiral quarks get mass from SM Higgs change gluon fusion Higgs production + Landau poles ) > This talk will focus on the following models: > P. Fileviez Pérez, M. B. Wise, JHEP 08 (2011) 068 > MD, P. Fileviez Pérez, M. B. Wise, PRL 110 (2013) 231801 > P. Fileviez Pérez, S. Ohmer, H. H. Patel, Phys. Rev. D 90 (2014) 037701 Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 10 Features of these models. > Framework for the spontaneous breaking of local baryon number at the low scale in agreement with experiments. > Proton is stable (or long-lived) think about the possibility of low-scale unification.! > Vector-like fermions F with baryon number to cancel anomalies (with or without color). > Cold dark matter candidate χ: lightest neutral field in the new sector. > Leptophobic gauge boson coupling to SM quarks and new fermions: ZB qq,¯ χχ, FF¯ ! > New Higgs Boson hB qq,¯ ZBZB, FF¯ ! > Connection between the DM and baryon asymmetries. Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 11 Outline. > Local baryon number > Baryonic dark matter > Baryon asymmetry > Collider signatures > Towards low-scale unification > Summary Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 12 Anomaly cancellation. > New gauge group: Field SU(3) SU(2) U(1)Y U(1)B U(1)L 1 1 QL 3 2 6 3 0 SU(3) SU(2) U(1)Y U(1)B 2 1 R 3 1 3 3 0 ⊗ ⊗ ⊗ 1 1 dR 3 1 3 3 0 − > Baryonic anomalies: νR 1 1 0 0 1 eR 1 1 1 0 1 − 1 2 2 2 H 1 2 2 0 0 1 SU(3) U(1)B , 2 SU(2) U(1)B , 3 U(1)Y U(1)B , A ⊗ A ⊗ A ⊗ 2 3 4 U(1)Y U(1)B , 5 (U(1)B) , 6 U(1)B . A ⊗ A A U(1)B Standard Model 3 SU(2)L SU(2)L 2 = 3 = ¡ A −A 2 > New fermions needed to cancel non-trivial anomalies > 0 simplest solution: colorless fields A1 = ) Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 13 How many new fermion multiplets?. > Two fermion multiplets ΨL (1, N, Y1,B1) and ΨR (1, M, Y2,B2) ∼ ∼ > U 1 0 requires B MB /N A5 ( ( )B) = 1 = 2 > Then U 1 3 0 requires M N and B B A6 ( )B = = 1 = 2 2 > 2 SU(2) U(1)B cannot be canceled A ⊗ > No solution with two new fermion multiplets [Fileviez Pérez, Ohmer, Patel, arXiv:1403.8029] Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 14 How many new fermion multiplets?. > Three fermion multiplets L (1, N, Y, B1), R (1, N, Y, B2), and χL (1, M, 0,B3) ∼ ∼ ∼ > Anomaly cancellation requires 2 2 3 M = 2N, Y = N /4,B1 = B2 = B3 = 3/N − − >χ L: fermions with fractional electric charge that cannot decay to SM particles > more general assignments lead to same conclusion > consistent with anomaly cancellation but in conflict with cosmology [Fileviez Pérez, Ohmer, Patel, arXiv:1403.8029] Michael Duerr | Gauge Theories for Baryon Number | 18 May 2017 | page 14 How many new fermion multiplets?.
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