1 / 8

ENCONTRANDO O BÓSON DE HIGGS ATRAVÉS DE SUPERSIMETRIA

ENCONTRANDO O BÓSON DE HIGGS ATRAVÉS DE SUPERSIMETRIA. Maur í cio B. Magro (CUFSA – Santo Andr é ) F. de Campos (FEG / UNESP - Guaratinguet á ) Oscar É boli (IFUSP – São Paulo) D. Restrepo (U. Antioquia - Colômbia) J. W. F. Valle (U. Valência - Espanha). SUPERSYMMETRY AND THE HIGGS BOSON.

zada
Download Presentation

ENCONTRANDO O BÓSON DE HIGGS ATRAVÉS DE SUPERSIMETRIA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ENCONTRANDO O BÓSON DE HIGGS ATRAVÉS DE SUPERSIMETRIA Maurício B. Magro (CUFSA – Santo André)F. de Campos (FEG / UNESP - Guaratinguetá)Oscar Éboli (IFUSP – São Paulo)D. Restrepo (U. Antioquia - Colômbia)J. W. F. Valle (U. Valência - Espanha)

  2. SUPERSYMMETRY AND THE HIGGS BOSON • The CERN LHC will test the origin of mass and the nature of electroweak symmetry breaking  Higgs Boson  Hierarchy Problem • Supersymmetry (SUSY) is a possible solution to the hierarchy problem; • Weak scale Supersymmetry breaking unifies gauge coupling constants and can include gravity; • SUSY is broken via SuperGravity ↓↓↓↓ New physics beyond the Standard Model

  3. THE BILINEAR R-PARITY MODEL IN mAMSB • In SUSY there is a multiplicative quantum number called R-parity: RP = (-1)2J+3B+L If R-parity is conserved: 1. SUSY particles are produced in pairs. 2. SUSY particles must decay into antother SUSY particles. 3. There is a stable SUSY particle: LSP (neutralino). • We introduced a bilinear term in the SUSY superpotential: εiLiHu that breaks R-parity explicitly.

  4. Consequences Only one neutrino aquires mass at tree level. The neutrino mass spectrum can be cosistent with neutrino oscillation data, favouring  → . The neutrino mass is given by: with Λi = νi + εiνd The neutrino mixing angles are given by: and The lightest nuetralino is unstable, therefore can decay inside the present detector colliders  New signatures at colliders. The Neutralino branching ratio into Higgs is:

  5. HIGGS SEARCH Neutralino Decays • It can decay through Higgs boson as: χ0→  H* .→ ν bb • The model backgrounds are: χ0→  Z* .→ ν bb and χ0.→ ν bb χ0→ τW.→ ν qq (mistaged b´s)

  6. The LSP can live long enough to produce a displaced vertex at detectors. • The displaced vertices have litte if none background at LHC • We have considered a neutralino that lives long enough to decay out the primary vertex and before the tracking detectors. • We have applied the following kinematic cuts: 1. All charged tracks must be inside the region of |η| < 2.5; 2. We considered a b-tagging efficiency of either 50% or 30%; 3. We required an isolated electon(muon) with pt > 20(6) GeV; or a jet with pt > 100 GeV; or missing tranverse energy Etmiss > 100 GeV; 4. We required an invariant mass inside the range 100 GeV < MH < 125 GeV;

  7. THE RESULTS • The parameters are: m1/2; m0; Tanβ = 10; sign() > 0; εi; Λi. - We have used SPheno code to calculate the R-Parity violating branching ratios and Pythia code to calculate the cross sections. - We required at least 5 background free events, consistent with neutrino data. Reach for LHC Reach for Tevatron 10 fb-1 (stars) and 100 fb-1 (squares) 2 fb-1 (stars) and 8 fb-1 (squares)

  8. Results Reach for LHC Reach for Tevatron 10 fb-1 (stars) and 100 fb-1 (squares) 2 fb-1 (stars) and 8 fb-1 (squares) low efficienciy • For more details, see Phys. Rev. D80, 015002 (2009).

More Related