Some model-independent phenomenological consequences of flexible brane-worlds IRGAC 2006 Barcelona, July J.A.R. Cembranos A. Dobado A. L. Maroto

IRGAC 2006Antonio L. Maroto2 Brane worlds: branons vs. KK gravitons Phenomenology in colliders Branons as dark matter Virtual branon effects Summary

IRGAC 2006Antonio L. Maroto3 Brane worlds: branons vs. KK gravitons

IRGAC 2006Antonio L. Maroto4 Introduction: brane worlds R fundamental scale of gravity in D = 4 +  dimensions brane tension Brane universe Brane hierarchy MDMD f4f4 ADD, 98 Antoniadis, et al. 98

IRGAC 2006Antonio L. Maroto5 Kaluza-Klein gravitons 3+1 coordinatesextra-dimensional coordinates KK graviton tower Linearizing the bulk gravitational field KK graviton mass (torus compactif.)

IRGAC 2006Antonio L. Maroto6 Coset space Isometry group of G MN Brane ground state Branons (brane fluctuations) Branons   (x) GB fields Spontaneous isometry breaking Brane position Sundrum, ‘99 Dobado, A.L.M. ‘01

IRGAC 2006Antonio L. Maroto7 Bulk metric: Branon mass related to bulk curvature: Induced metric on the brane: Branons

IRGAC 2006Antonio L. Maroto8 Branon dynamics Dirac-Nambu-Goto Induced metric

IRGAC 2006Antonio L. Maroto9 KK gravitons vs. branons KK-productionBranon production KK-SM coupling suppression Bando et al. ‘99

IRGAC 2006Antonio L. Maroto10 - Rigid branes ( f >> M D ) Kaluza-Klein modes Brane-world scenario - Flexible branes (f << M D ) Branon fields (KK modes decouple from SM) KK gravitons vs. branons

IRGAC 2006Antonio L. Maroto11 Phenomenology in colliders

IRGAC 2006Antonio L. Maroto12 Induced metric on the brane: Dirac - Nambu - Goto action: Branon action Limits from colliders LEP-II... TEVATRON-I +... hep-ex/ Cembranos, Dobado, A.L.M, ’03

IRGAC 2006Antonio L. Maroto13 Prospects for future colliders Single photon-Z Monojet (quark production) Monojet (gluon prod.)

IRGAC 2006Antonio L. Maroto14 Prospects for future colliders TEVATRON-IILHC ILC Cembranos, Dobado, A.L.M, ’04

IRGAC 2006Antonio L. Maroto15 Branons as dark matter

IRGAC 2006Antonio L. Maroto16 Brane orientation branons are pseudoscalar particles Parity on the brane branons couple by pairs to SM. (stable particles) Branons are stable, massive and weakly interacting particles NATURAL DARK MATTER CANDIDATES A new dark matter candidate Cembranos, Dobado, A.L.M, ’03

IRGAC 2006Antonio L. Maroto17 + e1e1  - ê1ê1  + e1e1 e2e2  + ê2ê2 ê1ê1 Parity on the brane Odd-dimensional branes: pseudoscalar branons Even-dimensional branes: scalar branons P P

IRGAC 2006Antonio L. Maroto18 Branon cosmic abundance Freeze-out in an expanding universe: Annihilation into all SM pairs X :, e.g. annihilation into photons, : Cold branons (M >> T) Hot branons (M << T)

IRGAC 2006Antonio L. Maroto19 Branon cosmic abundance Cold branons WMAP limits

IRGAC 2006Antonio L. Maroto20 Branon cosmic abundance Hot branons WMAP WMAP-CBI-ACBAR-2dF-Ly-  BBN limits (light branons): for

IRGAC 2006Antonio L. Maroto21 Combined limits

IRGAC 2006Antonio L. Maroto22 Direct detection Elastic branon-nucleon cross section (spin independent)

IRGAC 2006Antonio L. Maroto23 Non-thermal branon production (   M f 2 R B ) 1/2  explicit symmetry breaking scale). Branons are very light particles and decoupled from SM. Brane initial position: Y 0 = O (R B ) and    f 2 R B Dark matter as coherent brane oscillations (similar to axions) If H(T) >  (T) for T < T RH brane oscillations only diluted by Hubble expansion. Non-thermal branon abundance: A.L.M, ’04 If  << T RH << T f

IRGAC 2006Antonio L. Maroto24 Non-thermal branon production T f < (M M P ) 1/2

IRGAC 2006Antonio L. Maroto25 Virtual branon effects

IRGAC 2006Antonio L. Maroto26 Radiative corrections Cembranos, Dobado, A.L.M, ’06 One-loop SM effective action SM masses renormalization New SM vertices

IRGAC 2006Antonio L. Maroto27 Muon anomalous magnetic moment Cembranos, Dobado, A.L.M, ’06 Brookaven (g-2) coll. (2004) 2.7  above SM

IRGAC 2006Antonio L. Maroto28 Conclusions and future perspectives Low-energy branon dynamics universally described by effective action depending on 3 parameters (M,f,N) For f << M D only branons and SM particles relevant degrees of freedom. Limits on (M,f) from present and future colliders Loop effects contribute to the muon anomalous magnetic moment Branons are natural dark matter candidates (thermal or non- thermal production) Future detection in direct or indirect experiments?