SOME COMMENTS ON CP-VIOLATION AND LEPTOGENESIS

Transcription

1 Marco Drewes TU München , NuFact, Quy Nhon, Vietnam 1 / 7

2 The Standard Model and General Relativity together explain almost all phenomena observed in nature, but... gravity is not quantised a handful of observations remain unexplained neutrino oscillations - the only signal found in the lab! baryon asymmetry of the universe - leptogenesis? dark matter - sterile neutrinos? accelerated cosmic expansion (Dark Energy, inflation) planck.cf.ac.uk 2 / 7

3 125 GeV figure by M. Shaposhnikov 3 / 7

4 Introduction MaD/Garbrecht S OME COMMENTS ON CP- VIOLATION AND LEPTOGENESIS 4/7

5 High scale leptogenesis Lepton asymmetries are characterised by CP violating parameter ɛ α = 3 M 1 16π (F F) 11 v 2 Im [ ] F α1 (m ν ) αβ F β1 Φ lβ Φ Φ Φ NI NI NI NJ NJ lα Yukawa matrix F = 1 v U ν complex rotation matrix R m diag ν Φ lα R M M,Casas/Ibarra Vanilla leptogenesis Asymmetry only depends on ɛ = α ɛ α Dependency on U ν drops out baryon asymmetry only depends on complex "Euler angles" in R Flavoured leptogenesis No sum over α baryon asymmetry depends on both, complex angles in R and the phases in U ν lβ lα 5 / 7

6 Low scale leptogenesis I is experimentally accessible plot from MaD/Garbrecht/Gueter/Klaric see also Canetti/MaD/Frossard/Shaposhnikov Hernandez/Kekic/Lopez-Pavon/Salvado Abada/Arcadi/Domcke/Lucente can explain baryon asymmetry with PMNS phases alone M ev GeV 10 MeV 100 MeV GeV e Im Ω Canetti/MaD/Frossard/Shaposhnikov / 7

7 Low scale leptogenesis II δ affects active-sterile flavour mixing pattern Uμ 2 /U sin 2 θ23 = sin 2 θ23 = δ = Ue 2 /U 2 CP-violation in sterile sector may be measued at SHiP (?) Cvetic/Zamora-Saa 7 / 7

8 some slides that may be useful for the discussion 8 / 7

9 Neutrinos have masses. There is (almost) no antimatter in the observable universe. There are times more photons in the observable universe than nuclei. 9 / 7

10 Neutrinos have masses. There is (almost) no antimatter in the observable universe. There are times more photons in the observable universe than nuclei. We need New Physics! Could the same New Physics solve these puzzles? Can we probe it in the lab? 9 / 7

11 125 GeV figure by M. Shaposhnikov 10 / 7

12 Neutrino masses: Seesaw mechanism L = L SM + i ν R / ν R L L Fν R H νr F L H 1 2 ( ν c RM M ν R + ν R M M νc R ) Minkowski 1979, Gell-Mann/Ramond/Slansky 1979, Mohapatra/Senjanovic 1979, Yanagida 1980, Schechter/Valle ( 0 2 (ν L νr c ) md md T M M ) ( ν c L ν R two sets of Majorana mass states with mixing θ = m D M 1 M ) = vfm 1 M 11 / 7

13 Neutrino masses: Seesaw mechanism L = L SM + i ν R / ν R L L Fν R H νr F L H 1 2 ( ν c RM M ν R + ν R M M νc R ) Minkowski 1979, Gell-Mann/Ramond/Slansky 1979, Mohapatra/Senjanovic 1979, Yanagida 1980, Schechter/Valle ( 0 2 (ν L νr c ) md md T M M ) ( ν c L ν R two sets of Majorana mass states with mixing θ = m D M 1 M three light neutrinos ν U ν (ν L + θνr c ) mostly "active" SU(2) doublet light masses m ν θm M θ T = v 2 FM 1 F T three heavy neutrinos N ν R + θ T νl c mostly "sterile" singlets heavy masses M N M M M ) = vfm 1 M Majorana masses M M introduce new mass scale(s) M I new heavy states only interact via small mixing U 2 ai = θ ai / 7

14 Introduction MaD/Garbrecht S OME COMMENTS ON CP- VIOLATION AND LEPTOGENESIS 12 / 7

15 Leptogenesis: Sakharov conditions baryon number violation C and CP violation nonequilibrium 13 / 7

16 Leptogenesis: Sakharov conditions baryon number violation SM: sphalerons violate B, but conserve B L at T > 140 GeV C and CP violation SM: weak interaction violates P and CP, but CP-violation insufficient nonequilibrium SM: Hubble expansion unsufficient, no EW phase transition 13 / 7

17 Leptogenesis: Sakharov conditions baryon number violation SM: sphalerons violate B, but conserve B L at T > 140 GeV Yukawa couplings F violate individual lepton flavour numbers in addition M M violates total lepton number C and CP violation SM: weak interaction violates P and CP, but CP-violation insufficient nonequilibrium SM: Hubble expansion unsufficient, no EW phase transition 13 / 7

18 Leptogenesis: Sakharov conditions baryon number violation SM: sphalerons violate B, but conserve B L at T > 140 GeV Yukawa couplings F violate individual lepton flavour numbers in addition M M violates total lepton number C and CP violation SM: weak interaction violates P and CP, but CP-violation insufficient additional complex phases in F violate CP nonequilibrium SM: Hubble expansion unsufficient, no EW phase transition 13 / 7

19 Leptogenesis: Sakharov conditions baryon number violation SM: sphalerons violate B, but conserve B L at T > 140 GeV Yukawa couplings F violate individual lepton flavour numbers in addition M M violates total lepton number C and CP violation SM: weak interaction violates P and CP, but CP-violation insufficient additional complex phases in F violate CP nonequilibrium SM: Hubble expansion unsufficient, no EW phase transition N I production ("freeze in leptogenesis") Akhmedov/Rubakov/Smirnov N I freezeout and decay ("freeze out leptogenesis") Yeq Y Fukugita/Yanagida M/T 13 / 7

20 Vanilla Leptogenesis (freeze out)fukugita/yanagida N I are produced thermally very early at T > M freeze out and decay at T M CP-violating decay produces L 0 NI Φ NI lβ Φ NI Φ NJ Φ NJ lα Φ lα lβ lα L 0 is partly transferred into B 0 by sphalerons Boltzmann equations (x = M/T ) see e.g. Buchmüller/Plümacher xh dy N dx xh dy B L dx = Γ N (Y N Y eq N ) = ɛγ N (Y N Y eq N ) c W Γ N Y B L 14 / 7

21 first principles derivation of kinetic equations Anisimov/Buchmuller/MaD/Mendizabal, Beneke/Garbrecht/Herranen/Schwaller, Garny/Hohenegger/Kartavtsev, Dev/Millington/Pilaftsis/Teresi quasiparticle dispersion relations Giudice/Notari/Raidal/Riotto 04, Plumacher/Kiessig 12 momentum dependency Hahn-Woernle/Plumacher/Wong 09, Asaks/Eijima/Ishida 12, Bodeker/Wormann 14 production rate Γ N Salvio/Lodone/Strumia 11, Laine 12, Besak/Bodeker 12, Biondini/Brambilla/Escobedo/Vairo 13, Garbrecht/Glowna/Herranen 13, Garbrecht/Glowna/Schwaller 13, Ghisoiu/Laine 14, Ghiglieri/Laine 15, Ghiglieri/Laine 16 washout rates c W Γ N Bodeker/Laine 14, Ghisoiu/Laine 14, Ghiglieri/Laine 16 CP violating parameter ɛ Biondini/Brambilla/Escobedo/Vairo 15 behaviour near resonance Garny/Hohenegger/Kartavtsev 11, Garbrecht/Herranen 11, Dev/Millington/Pilaftsis/Teresi 11 flavour effects Abada/Davidson/Ibarra/Josse-Michaux/Losada/Riotto 06, Nardi/Nir/Roulet/Racker 06, Jose-Michaux/Abada 07, Aristazabal Sierra/Munoz/Nardi 09, Racker/Pena/Rius 12, Beneke/Fidler/Garbrecht/Herranen/Schwaller 11,... low scale leptogenesis parameter space this talk 15 / 7

22 Low scale leptogenesis Y Y eq M/T 16 / 7

23 Leptogenesis from N-oscillations (freeze-in) Oscillating regime 17 / 7

24 Leptogenesis from N-oscillations (freeze-in) Oscillating regime Overdamped regime 17 / 7

25 Leptogenesis with two heavy neutrinos plot from MaD/Garbrecht/Gueter/Klaric see also Canetti/MaD/Frossard/Shaposhnikov , Hernandez/Kekic/Lopez-Pavon/Salvado and Abada/Arcadi/Domcke/Lucente Requires mass degeneracy and small mixing......but CP-violation may also be measurable Cvetic/Kim/Zamora-Saa / 7

26 0.5 Flavour mixing predictions 0.4 U Uμ 2 /U Ue 2 /U 2 allowed relative mixings U 2 a /U 2 for given U 2 and M = 1 GeV and IH measuring Dirac phase δ would considerably reduce allowed regions 19 / 7

27 How to find the N I? see e.g. MaD arxiv: [hep-ph] Indirect searches see e.g. MaD/Garbrecht Direct searches see e.g. Antusch/Fischer , Deppisch/Dev Cosmology: BBN and N eff see e.g. Hernandez/Kekic/Lopez-Pavon Astrophysics: X-ray, SN, pulsars, structure formation review / 7

28 How to find the N I? see e.g. MaD arxiv: [hep-ph] Indirect searches see e.g. MaD/Garbrecht neutrino oscillation data LFV in rare lepton decays violation of lepton universality, (apparent) violation of CKM unitarity neutrinoless double β-decay EW precision data Direct searches see e.g. Antusch/Fischer , Deppisch/Dev Cosmology: BBN and N eff see e.g. Hernandez/Kekic/Lopez-Pavon Astrophysics: X-ray, SN, pulsars, structure formation review / 7

29 How to find the N I? see e.g. MaD arxiv: [hep-ph] Indirect searches see e.g. MaD/Garbrecht neutrino oscillation data LFV in rare lepton decays violation of lepton universality, (apparent) violation of CKM unitarity neutrinoless double β-decay EW precision data Direct searches see e.g. Antusch/Fischer , Deppisch/Dev LNV and LFV in gauge boson or meson decays D, B N meson or lepton antilepton displaced vertices, SHiP peak searches, missing 4-momentum l l Cosmology: BBN and N eff see e.g. Hernandez/Kekic/Lopez-Pavon Astrophysics: X-ray, SN, pulsars, structure formation review / 7

30 Direct searches plot by Bhupal Dev see talks by Bhupal Dev, Un-ki Yang, Eric van Herwijnen 21 / 7

31 Introduction Indirect searches Example: leptogenesis and neutrinoless double β-decay 10-9 range of KamLAND-Zen upper limit mββ [GeV] M [GeV] plot from MaD/Eijima see also Hernandez/Kekic/Lopez-Pavon/Racker/Salvado , Asaka/Eijima/Hiroyuki S OME COMMENTS ON CP- VIOLATION AND LEPTOGENESIS 22 / 7

32 Summary Heavy right handed neutrinos can be the common origin of neutrino masses and baryons in the universe. Much progress has been made in the quantitative understanding of leptogenesis If the heavy neutrino masses are below the TeV scale, they can be found in experiments. The requirement to explain the neutrino masses and the baryon asymmetry impose strong constraints on the properties of the heavy neutrinos. If any heavy neutral leptons are found in experiments in the future, these can be used to asses whether the new particles are indeed the common origin of neutrino masses and matter in the universe. 23 / 7