Leaders: Katsuo TOKUSHUKU (KEK) Jean-Francois GRIVAZ (LAL) LHC_04: Search for a low mass Higgs using the VBFττ and 4-leptons modes. Leaders: Katsuo TOKUSHUKU (KEK) Jean-Francois GRIVAZ (LAL)

Members French side (Orsay, LAL) Japanese side (KEK) Jean-Francois Grivaz (Leader) Jean-Baptiste De Vivie Reisaburo Tanaka Lydia Iconomidou-Fayard Yu Nakahama Jean-baptiste Sauvan David Rousseau Marthe Teinturier Daniel Fournier Arthur Schaffer Japanese side (KEK) Katsuo Tokushuku (Leader) Masaya Ishino Junichi Kanzaki Soshi Tsuno Kunihiro Nagano Junji Tojo

Scope of the project The discovery of the Higgs boson is the major goal of the LHC. Higgs (depending on its mass) decays with various modes. – Combined information from different detectors is required to cover a wide mass region. The kick-off meeting was held at CERN on 4/May. Useful information exchange took place.

Start of LHC physics program Excitement of the first collisions (ECM=900GeV) on 23/Nov/2009, 7TeV Collisions on 30/March/2010. 3/3/2010

2009 ~10mb-1 Jun/2010 ~15nb-1 2011 1fb-1 W, Z re-(re-)discovery is done. Now reaching to the Top –level. Higgs in 2011?

Higgs is hard to catch. -> Project toward 2014-15 Comination of H->VV and H->tau tau (and H-> g g) covers the most of the mass region. Ecm=14TeV

But still there is small chances If Higgs mass is ~160 GeV or if SUSY-Higgs with a large tan(b) g H q H

Not yet Higgs ! but now we start seeing handful(3) Z’s and several tens(57) W’s (4.8 and 51.8 exepcted, resptvly) First 900GeV Collisions were successfully recorded on 23/Nov/2009 3/3/2010

ATLAS Collaboration: ~3000 physicists from 173 Institutions and 37 Countries Two-institute collaboration inside a large collaboration is important.

Why LAL- KEK collaboration? Major LAL contributions Major KEK contributions Because we are complimentary in detector experties and in physics (KEK: tau/mu LAL: e/gamma) 3/3/2010

Detailed detector studies Dead materials in front of LAr Muon Trigger Timing Photons will convert depending on the material amount in front of the calorimeter Good Level-1 Trigger timing Beam pipe Pixel 1 Pixel 2 Pixel 3 SCT 1 SCT 2 Compare the conversion position of data and MC

J/psi seen in both ee and mumu modes

We like to see this in GeV scale! And Mgg We like to see this in GeV scale!

Planned Activities The kick-off meeting at CERN on 4/May. A few collaboration meetings a year at CERN or LAL/KEK (connected to conference) on detector status update, signal objects (e, mu, tau) reconstructions, and then forming a physics analysis team. 2010: ICHEP and Higgs workshop in Paris: 2011: Hadron collider physics (HCP) in Paris 2012: Hadron collider physcis (HCP) in Japan

Budget Request French side: support for a post-doc : 19800 euros travel (2 x LAL -> KEK) : 4100 euros Japanese side: travel ( 6 CERN -> LAL visits + 1 KEK-> LAL visit) : 1020 k yen (10000 euros)