Affleck-Dine Leptogenesis induced by the Flaton of Thermal Inflation

1. Summer Institute 2006: August 23-30, 2006 APTCP, Pohang, Korea Affleck-Dine Leptogenesis induced by the Flaton of Thermal Inflation Based on JHEP 0411:046,2004(hep-ph/0406136) Wan-il Park KAIST Korea Advanced Institute of Science and Technology

2. Contents • Introduction • Motivation • Model • Dynamics • Summary & Conclusion

3. Inflation Introduction • Matter-antimatter asymmetry • Observed asymmetry } • Direct measurement (galaxy survey) • Abundances of light elements (BBN) • Density perturbation (CMBR) - Is this given as initial condition of universe? • Dynamical generation of asymmetry is required after inflation: Baryogenesis !!!

4. Introduction • Basic ingredients of baryogenesis (Sakharov, 1967) • Baryon number violation • C and CP-violation • Departure from thermal equilibrium • Several types of baryogenesis • GUTbaryogenesis, leptogenesis (Yoshimura, 1978; Fukugita and Yanagida, 1986) • uses heavyparticledecay • → very high energy scale ~ GUT scale • Electroweak baryogenesis (Kuzmin, Rubakov and Shaposhnikov, 1985) • uses sphaleron, electroweak phase transition • → around electroweak scale, minimal extension of SM • Affleck-Dine(AD) baryogenesis (Affleck and Dine, 1985) • uses MSSM-flat directions • → intermediate scale, very simple and efficient

5. Introduction • Unwanted relics produced after inflation (gravitino, moduli problem) • Unwanted? Why? - Large enery density → “over closing” universe - Long life time with large number density → disturbing successful BBN, etc. * Primordial inflation can dilute sufficiently some heavy unwanted relics, for example, monopoles • Properties - Small mass→ thermal reproduction after reheating - Gravitationally suppressed weak coupling → late time decay or stable • Gravitino problem (Khlopov and Linde, 1984; etc.)

6. * Initial abundance ? < > ~ ~ * Observational constraint Introduction • Moduli problem (Coughlan, et. al., 1983; etc.) Large entropy release is required

7. due to thermal mass inflation! → Low scale → small number of e-folds Thermal Inflation * Dilution factor: Introduction * Thermal inflation (Lyth and Stewart, 1995)

8. 1. GUT baryogenesis & leptogenesis 2. Affleck-Dine baryogenesis Thermal Inflation Electroweak baryogenesis Flaton decay • Too low temperature • no baryogenesis mechanism can work New model ? Motivation • Incompatibility between thermal inflation and baryogenesis Coherent oscillation of moduli field

9. Motivation • The required features for new model • Working era: after thermal inflation to avoid dilution, • before flaton decay to avoid too low energy scale - Efficiency: efficient from dilution by entropy release due to flaton decay => Proper base of new model = Affleck-Dine mechanismdue to its efficiency * Affleck-Dine mechanism Angular momentum = charge asymmetry - Setting initial condition: Hubble terms due to SUSY-breaking effect of finite energy of early universe

10. Model • MSSM superpotential • Our superpotential -term Neutrino mass term Flaton self interaction term with (D. Jeong, K. Kadota, W. I. Park and E. D. Stewart, 2004) • Superpotential, W

11. Model • Ansatz & Potential • Ansatz :Only and flaton have nonzero values • Simplification : Consideration of just single generation • Potential : where

12. Dynamics - : is unstable at the end of thermal inflation - : is unstable near the end of thermal inflation - rolls away first, then • Key assumptions - All fields are held at origin initially due to thermal effect

13. 2b. becomes nonzero, → stabilizes dangerous directions 1a. rolls away 1c. Fixes initial phase of 2a. rolls away 2c. Fixes phase of 3c. Stabilizes 3a. Brings back into origin 1b. Stabilizes 3b. Rotates the phase of Dynamics

14. Dynamics

15. ? Dynamics • Potential problems • Problem due to MSSM • Deeper non-MSSM minima do exist • (see “Casas, Lleyda and Munoz, 1995”) Non-MSSM • Way of resolution - Avoiding being trapped : dynamical settling down in our vacuum - Stability of our vacuum : τ > 1/H τ = the time scale for quantum tunnelling to the minima 1/H = the age of our universe • How about our model? - Stability of our vacuum : τ > 1/H in large enough parameter space (see “Kusenko, Langacker and Segre, 1996”)

16. deeper non-MSSM minimum exists with nonzero but Give terms linearin Gives large mass to q Gives negative mass squared to q where Dynamics - Avoiding being trapped: • All the fields settle down in our vacuum!!!

17. Dynamics • Simulation results (homogeneous mode) Dynamics of AD-field Lepton number asymmetry

18. decay when field passes near the origin Dynamics • Preserving lepton asymmetry Damping Preheating: energy transfer from homogeneous modes to inhomogeneous modes Thermal friction:

19. to to < < ~ ~ Dynamics • Estimation of baryon asymmetry { we expect

20. Preliminary simulation result including preheating effect

21. Summary & Conclusion • becomes nonzero • stabilizes dangerous directions • Brief history of thermal inflation Moduli Domination held at origin held at origin held at origin Thermal Inflation rolls away • rolls away • ends thermal inflaton reaches its VEV • brought back into origin with phase rotation • generation of L-asymmetry Flaton Domination • decays • partial reheating • EW symmetry restoration • L-asymmetry → B-asymmetry oscillates decays B-asymmetry diluted but survives Radiation Domination radiation domination BBN

22. Summary & Conclusion • Conclusions • Baryogenesis compatible with thermal inflation was proposed. • Fairly minimal in the sense of particle physics theory. • Unique in the context of gravity mediated SUSY breaking and thermal inflation. • Flaton generated the -term and triggered the generation of lepton asymmetry. • Complete analysis of the damping of field is required as future work. • Our vacuum is unstable, but cosmological evolution leads to our vacuum. • can be tested at future particle accelerators.