1. Barbara Mele Sezione di Roma
Roma, 12 ottobre 2005
Physics : ILC vs LHC
….after Snowmass 2005
Barbara Mele
Sezione di Roma

3. Advances in Physics at Snowmass
Higgs
Supersymmetry
Beyond the Standard Model
Top / Quantum Chromodynamics
LHC/ILC Connections
Cosmological Connections
Radiative Corrections (Loopfest)

4. The Charge for the Physics Working Groups
1. What are the most important measurements that the ILC should perform in the subject area of your working group?
2. What are the key measurements by which the ILC will add to what is already known from the LHC?
3. What are the processes and measurements new to the community
in the past few years that further motivate the case for the ILC?
4. For each of these measurements, what criteria for the detectors are necessary to allow measurements to the appropriate precision?
5. Are there detector capabilities that are not strongly challenged by
the list of processes in #1 and #2? Is this acceptable, or are there
additional measurements that should be added to the list against
which detectors will be evaluated?

5. 485 pages !
started in Spring 2002
~ 120 authors
. . .

6. Precision Higgs physics at the ILC
model-independent observation
mass
absolute branching ratios
total width (mod.indep.)
spin, CP
top Yukawa coupling
self coupling
most measurements at the percent level!
Garcia-Abia et al

10. Supersymmetry Two methods to obtain absolute sparticle masses:
in the continuum:
at the kinematic threshold:
(polarized beams)
Freitas
Martyn
mass precision 0/00 – 0/0
many more observables than just masses:
angular distributions, FB-asymmetries - cross sections - LR-asymmetries - ratios of branching ratios
possibility to determine SUSY parameters without many model assumptions

11. LHC: Mass determination for 300fb-1 (thus 2014) LHC:
Toy MC from edges, thresholds to masses
Polesello et al: use of χ1 from ILC (high precision) in LHC analyses improves the mass determination
D. Zerwas, Snowmass talk
Allanach et al

12. MSSM parameter determination

13. SUSY W-group conclusions

14. The Cosmic Connection
SUSY provides excellent candidate for dark matter (LSP)
Other models also provide TeV-scale WIMPs
How well can the properties of the DM-candidates (to be found at accelerators) be compared to the properties of the real DM (inferred from astrophysical measurements) ?
ALCPG study/prel.
DM/DM main sensitivity
bulk 3.5%
focus 1.9%
co-ann. 6.5%
funnel 3.1%
matches precision of future CMB exp.

15. Dark Matter : is it the Susy LSP ?

16. Difficult at LHC

17. No elementary Higgs?
Cross section for vector boson scattering violates unitarity
at ~1.2 TeV, if forces remain weak and no new resonances appear
ILC sensitivity deep into multi-TeV region from VB final states
eff. Lagrangian parameters of strong EWSB:
Higgsless model: new resonance in WZWZ
Coupling structure from ILC if resonance seen by LHC
Birkedal et al.
Krstonosic et al.

18. Effective 4-fermion contact interactions

19. What if “unexpected” New Physics ?

20. Top
it’s there for sure! Threshold scan provides excellent mass measurement Theory (NNLL) controls mt(MS) to 100 MeV
precise mtop vital for
improved SM fits - MSSM (mh prediction) - DM-density in mSugra
Heinemeyer et al
Hoang et al

22. EW precision measurements :

26. Phisics Benchmarks for the ILC detectors