1. B. Dutta Texas A&M University Phys.Rev.Lett.99:261301, 2007; To appear Inflation, Dark Matter and Neutrino Masses Collaborators: Rouzbeh Allahverdi, Anupam Mazumdar ICHEP ‘08

2. Inflation and Dark Matter: Needs new physics What is this well motivated model particle physics model? Neutrino masses are small and require new physics: Can they be tied to this model? How can we test this model? Where? LHC, dark matter detection … How economically can we achieve all these? Introduction

3. We consider supersymmetry Dark Matter Candidate ~ (weak scale) Inflaton Mass ~ (weak scale) Sneutrino (spin 0) is the candidate Scalar Inflaton field contains the DM particle  Sneutrino Left Sneutrinos are ruled out as dark matter candidates We will consider New Sneutrinos Supersymmetry Framework

4. We consider simple extension: SU(3) x SU(2) L x U(1) Y x U(1) B-L B-L sneutrino can be the dark matter candidate U(1) B-L gets broken at a TeV or so We have an extra Z’ and 3 more neutralinos This is a minimal extension of the SM Model The model provides Dirac mass for neutrinos

5. The inflaton is composed of : Higgs field, Slepton and Sneutrino The corresponding flat direction : NH u L (W h NH u L) The mass of the flat direction is described in terms of the sparticle masses  O(weak scale) The mass of the inflaton,  ~ O(weak scale) Inflaton Note: DM candidate sneutrino is a part of the inflaton where, Flat direction and MSSM [Allahverdi, Enqvist, Kusenko, Mazumdar…]

6. The potential along the flat direction : h is the Yukawa coupling For A = 4 m   We get V’(  0 )=0 V’’(  0 )=0 but V’’’(  0 ) 0 V(  )=V(  0 )+1/3!V’’’(  0 )(  -  0 ) 3 +… Potential for inflation V 

7. In order to fit the CMBR result we need h~10 -12 We need this small coupling to explain the neutrino mass We have Dirac neutrinos  =h M ~O(0.1) eV Tiny neutrino mass arises when we explain inflation in this model Small Neutrino Mass

8. Inflaton is related to the neutrino mass:  H ~ 1.91 x 10 -5 Amplitude of Perturbations :  H ~ f(m,m ,  0 ) Inflaton vs neutrino masses Phys.Rev.Lett.99:261301, 2007

9. Inflaton and sparticle masses are correlated We use SUGRA boundary condition =1200 GeV m g ~ 1640 GeV 730 GeV m =0.3 eV Each line: Left end m 0 =0; Right end : M(sneutrino)=M(neutralino) Inflaton and other SUSY masses

10. Dark matter content is explained: Sneutrino is the LSP Sneutrino component of inflaton has never decayed - prime: t –channel, Z-prime: s-channel Z ~ Dark Matter Content Phys.Rev.Lett.99:261301, 2007

11. Direct Detection of dark matter LHC: Signal is similar as in the standard scenario with neutralino LSP If we can identify the spin of dark matter particle it is possible extract this model Work in progress… N ~ interacts with quark via Z’ exchange Typical cross section : 2 x10 -8 pb for Z’ mass ~ 2 TeV Collider Signal: Signal However, sneutrino has spin 0

12. Conclusion It is possible to explain Inflation and dark matter in the context of particle physics model We need to extend the MSSM by an extra U(1) symmetry Sneutrino is the dark matter candidate which is part of the flat direction for inflation Dark Matter content can be satisfied Direct detection experiment can observe it One can distinguish this scenario at the LHC if the spin of the missing particle can be measured