Seung J. Lee KAIST So Far Nothing but Higgs…

Perspective on Future Circular Colliders Seung J. Lee KAIST So far nothing but Higgs…

Courtesy of C. Grojean Where are we now, after Higgs Discover?

M.L. Mangano, Aspen `14 Where to go? • The details for the future plan will be depending on the outcome of Run 2 of the LHC (13TeV), less than three years from now!

• But in every scenario, we will need ~100 TeV machine eventually Perspective

• Precision Higgs coupling measurements will be critical (e.g. ZZh coupling probe light states that couple to the Higgs) uncolored top partner Invisible Zh coupling shift � h h �

h h h h Perspective

• Precision Higgs coupling measurements will be critical (e.g. ZZh coupling probe light states that couple to the Higgs) uncolored top partner Invisible Zh coupling shift � h h �

h h h h New era of precision studies of the Higgs sector (from Snowmass Higgs working group report): Higgs precision will approach that of EWP Higgs Potential

• we need to understand the underlying dynamics of the EWSB Higgs Potential

• we need to understand the underlying dynamics of the EWSB Need to study/explore the restoration of SU(2)LxU(1)

• Need to go to energy up to 4� v / g => common argument for why we need a future pp collider High Luminosity vs High energy

A. Weiler

Obviously you can test naturalness further with higher energy Challenges

• heavier masses yield more boosted tops; new strategies will be required

Cohen, D’Agnolo, Hance, Lou, Wacker [arxiv:1406.4512] What’s going on now? European Side ECFA European Committee for Future Accelerators 2013

ECFA mandate includes “Monitoring of the ongoing implementation of the European Strategy for Particle Physics”

Discussion on future (post-LHC) accelerators: ! ILC and CLIC: continuous support through the ECFA LC study

! FCC (Future Circular Collider): RECFA strongly supports the proposed design study! ECFA represented in steering committee

Goal: Have studies available at the time of the next European Strategy Update in sufficient details on physics case, technological feasibility and with stable cost estimates. ECFA European Committee for Future Accelerators 2013

ECFA mandate includes “Monitoring of the ongoing implementation of the European Strategy for Particle Physics”

Discussion on future (post-LHC) accelerators: ! ILC and CLIC: continuous support through the ECFA LC study

! FCC (Future Circular Collider): RECFA strongly supports the proposed design study! ECFA represented in steering committee

Goal: Have studies available at the time of the next European Strategy Update in sufficient details on physics case, technological feasibility and with stable cost estimates. CERN COUNCIL DECISION

Slides'from'M.'Benedikt''

FCC Kick-Off 2014

Future Circular Collider (FCC) Study

Future Circular Collider Study FCC Kick-Off 2014 R-D Heuer, CERN ‹#› Why

Future Circular Collider Study FCC Kick-Off 2014 ‹#› Why

• Push the energy frontier beyond LHC

Future Circular Collider Study FCC Kick-Off 2014 ‹#› Why

• Push the energy frontier beyond LHC • High Priority item within the European Strategy for Particle Physics

Future Circular Collider Study FCC Kick-Off 2014 ‹#› Why

• Push the energy frontier beyond LHC • High Priority item within the European Strategy for Particle Physics • Timely lead times for R&D very long LHC physics program for ~20 years

Future Circular Collider Study FCC Kick-Off 2014 ‹#› Why

• Push the energy frontier beyond LHC • High Priority item within the European Strategy for Particle Physics • Timely lead times for R&D very long LHC physics program for ~20 years • Need for a project plan when LHC results indicate direction to go

Future Circular Collider Study FCC Kick-Off 2014 ‹#› Why