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Determination of the Determination of the Higgs-Fermion Yukawa couplings Higgs-Fermion Yukawa couplings
at future collidersat future collidersMarkus Schumacher, Bonn University
WE Heraeus Summer School on Flavour Physics and CP Violation Dresden, 29 August to 7 September
IntroductionIntroduction
Higgs boson discovery and Higgs boson discovery and
1st measurements at LHC 1st measurements at LHC
Precision measurements at ILC Precision measurements at ILC
Synergy of LHC and ILC for gSynergy of LHC and ILC for gtt
ConclusionsConclusions
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 2 / 45
The Higgs Mechanism in the Nut Shell
gauge symmetry no masses for W and Z
different reps. for left- a. rightchiral fields no masses for fermions
The problem: (for details see lecture by Marek Jezabek)
The „standard“ solution:
new doublet of scalar fields
with appropiately choosen potential V
vacuum spontaneously breaks gauge symmetry
one new particle: the Higgs boson H
= v + H
effective mass terms =
friction of particles
with omnipresent „Äther“
v =247 GeVx
fermion
gf
mf = gf v / sqrt(2)
gf is Yukawa coupling
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 3 / 45
The Higgs Mechanism in the Nut Shell
Higgs Boson couplings:
one unknown parameter in SM: mass of Higgs boson MH
MH completely determines Higgs phenomenology in SM
Loop induced effective couplings:
(sensitive to new physics)
Photon: g = gW “+“ gt “+“…
Gluon: g = gt “+“ gb “+“…
Hx
x
Born level couplings:
Fermions gf= mf / v
W/Z Bosons: gV= 2 MV / v
v = (sqrt(2) G)-1/2 =247GeV
2
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 4 / 45
The situation after LEP and from TEVATRON
Today: only discuss SM like Higgs boson with mass below 200 GeV
MH < 186 GeV
from EW fit (EPS05)
direct search:
MH<114.4 GeV
excluded by LEP
at 95% CL
MSSM: theory Mh <134 GeV (MSUSY=1TeV, mtop =175 GeV)
LEP Mh<92.9 GeV MA<93.4 excluded at 95% CL
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 5 / 45
50 100 200 100010-3
10-2
10-1
100
bb cc tt gg WW ZZ
Bra
nchi
ng r
atio (Higgs
)
mH (GeV)
bb
WW
ZZ
tt
ccgg
Higgs Boson Decays in SM
for M<135 GeV: H bb, dominant
for M>135 GeV: H WW, ZZ dominant
channels which can be identified and observed:
LHC: WW,ZZ, bb,
ILC: WW,ZZ,,Z bb,, cc udsg ()
HDECAY: Djouadi, Spira et al.
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 6 / 45
1) mass (LHC, ILC)
2) quantum numbers: spin and CP (LHC, ILC dep. on MH)
3) BRs, total width, couplings
4) self coupling (non vanishing at SLHC?, meas. only at ILC)
Higgs Physics at Future Colliders
discovery at LHC (SM like or at least one in MSSM)
investigation of Higgs boson profile
start at LHC and continue with higher precision at ILC
future colliders:
LHC: pp collisions at 14 TeV start in 2007
ILC: e+e- collisions between 90 and 800++ GEV start in 201x?
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 7 / 45
Why and how to access the couplings ?
partial width: Hz ~ gHz2
experiment measures rate: rate = Nsig+NBG
Nsig=L x efficiency x Hx x BR
need to know: luminosity, efficiency, background
Hx x BR ~ HX Hy
tot
tasks: disentangle contribution from production and decay
determine tot (tot << mass resolution for MH <200 GeV)
Why ? precision test of the hopefully discovered Higgs sector
look for deviations from SM prediction
hint towards new physics (SUSY, ED, Little H, TC)
Higgs couplings enter production and decay
Hx = const x Hx BR(Hyy) = Hy / tot
How ?
prod decay
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 8 / 45
pp collider /LHC and e+e- collider / ILCcollision of pointlike particle with known energy ECM = 2 Ebeam
high enery difficult to achieve
well defined quantum numbersand four momentum of initial state
production via el.-weak interaction smaller theo. uncertainties
“simple” final states, “moderate” background
no trigger needed
purely hadronic final statesselectable and reconstructable
Higgs: decay mode independent observation
moderate radiation exposure
suited for discoveries and precision measurements
collision of composed particleswith unknown energy ECM< 2 Ebeam
high energies easily achievable
quantum numbers of hard processnot known, only PT=0
production via strong interaction QCD uncertainty, PDF uncertainty
complex final states, overlaping events, huge background sophisticated trigger needed
purely hadronic final states can hardly be triggered and selected
Higgs: need identification of decay for observation
very high radiation level best suited for discoveries (energy frontier) and first measurementshadron and lepton collider are complementary !!
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 9 / 45
Comparison of cross sections
LHC: Higgs 150 GeV
S/B <= 10-10
ILC: Higgs 120 GeV
S/B >= 10-2
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 10 / 45
LHCLHCpp collisions
ECM = 14 TeV
start: 2007
tbunch = 25 ns
Luminosity:
first years: L= 12 1033/(cm2s) >10 fb-1 / year
later: L= 1034/(cm2s) 100 fb-1 / year
~23 overlaying minimum bias events
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 11 / 45
Production of the SM Higgs Boson at LHC
K~2.0
K~1.2
K~1.1
K~1.3
K = NLO / LO
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 12 / 45
uds = 0.005
Two multipurpose detectors at LHC: ATLAS and CMS
pixel vertex a. strip tracking detectors b andtagging (H, bb)
homogenous calorimeters up to e/ meas. (H,H4
lept.)
(pseudorapidtiy = -ln tan forward jet tagging (VBF)
missing energy (HHinv.)
complex myon spectrometers momentum accuracy and
eff. trigger (HZZ4 , A/H)
ATLAS CMS
detectors optimised for discovery of low mass Higgs boson
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 13 / 45
Discovery Potential for light SM Higgs boson
discovery channels:
GGF: H GGF: H ZZ 4l+-
GGF: H WW2(l)
tth: H bb
VBF: H
VBF: H WW
discovery with 10fb-1 for masses between LEP exclusion and 1 TeV
Exclu
ded
by
LEP
need photon, lepton or missing energy for trigger a. background supp. no sensitivity for fully hadronic final states signal processes with largest rate not useable e.g. GGF with Hbb
need identification of Higgs boson decay mode for observation !!!
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 14 / 45
Gluon Fusion: H and H ZZ 4 leptons
100 fb-1
MH=130GeVH signature two high Pt
Even
ts /
GeV
M: ~1GeV
K=1.6
S/BG ~ 1/20
4 high pt leptons narrow mass peak, small and flat background irreducible BG: ZZ reducible BG: tt, Zbb rejection via lepton isolation and b-veto mass resolution M: ~1%
HZZ4 leptons:
irreducible BG: pp +x mass resolution M: ~1% precise background estimate from sidebands ~ 0.1%
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 15 / 45
ttH with Hbb
signature: 1 lepton, missing energy,
6 jets of which 4 b-tagged
mbb ~ mH
mass resolution M: ~ 15%
difficult background estimate from
data foreseen, uncertainty ~ O(10 %)
reducible BG: tt+jets,W+jets b-tagging irreducible BG: ttbb reconstruct mass peak
exp. issue: full reconstruction of ttH final state b-tagging + jet/missing energy performance understanding of whole detector needed !
S/BG ~ 1/6
30 fb-1
only channel to see Hbb
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 16 / 45
Forward tagging jets
Higgs Decay
signature: - 2 forward jets with large
- only Higgs decay products
in central part of detector
Jet
Jet
Vector Boson Fusion
- forward jet reconstruction
- jet-veto fake rate due to pile up
- missing energy resolution
exp. issues:
decay modes: H WW l l and l j j
H l l and l had
only studied for low luminosity running results for 30 fb-1
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 17 / 45
MH=160 GeVHWWe
ATLAS
10 fb-1
ATLAS
He
Vector Boson Fusion
S/BG ~ 3.5/1
background: tt
no mass peak transverse mass
BG uncertainty ~ 10 %
S/BG ~ 1 to 2 / 1
background: Zjj
mass resolution ~ 10%
BG uncertainty ~ 5 to 10%
30 fb-1
MH=120 GeV
only channel to see H
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 18 / 45
Measurement of Higgs Boson Mass
1fb300L
ATLAS
M/M: 0.1% to 1%
Uncertainties considered:
“Indirect” from Likelihood fit to transverse mass spectrum: HWWllWHWWWlll
Direct from mass peak: HHbb HZZ4l
VBF with H or WW not studied yet
No theoretical errors considered: effect of PDF <<10 MeV
i) statistical ii) absolute energy scale 0.1% (goal: 0.02%) for l, 1% for jets iii) 5% on BG and signal rates for HWW channels
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 19 / 45
Strategy of Coupling Determination at LHC
assumption: CP-even, Spin=0 (several mass degenerate states fine)
only measurement of rates
only one Higgs boson
ratios of BRs = ratios of partial decay widths
= ratios of squared couplings, if only Born level couplings involved
further theoretical assumptions needed in order to constrain tot
measurement of couplings
t
W
Wg
WW
CorrWW)BR(HWW)BR(H
GF
WH
→
→
Direct: VBF
Indirect: e.g.
W
W
WW
ττ)BR(HWW)BR(H
VBF
VBF
→
→old study, Zeppenfeld et al.
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 20 / 45
Overview of 13 Channels used in new ATLAS Study
Production Decay Mass range
Gluon fusion
HHZZ4l HWW(*) l l
110 – 150 GeV 120 – 200 GeV 110 – 200 GeV
Vector Boson Fusion*
HH HWW(*)l lHZZ4l
110 – 150 GeV 110 – 150 GeV 110 – 190 GeV 110 – 200 GeV
ttH
HHbbHWWl l
110 – 120 GeV 110 – 140 GeV 120 – 200 GeV
WHHHWWl ll
110 – 120 GeV 150 – 190 GeV
ZH H 110 – 120 GeV* only studied for low lumi running, L= 30fb-1
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 21 / 45
CP even Spin 0: Measurement of Rates
Simultaneous fit of signal rates x BR in all 13 channels
Takes into account: cross talk between channels (e.g. GF events selected in VBF analysis) statistical fluctuations detector effects: Lumi, eff. tau, b-, forward jet tagging, and e background estimates: sidebands + shape + theoretical prediction uncertainties to signal rate from PDFs and QCD corrections
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 22 / 45
One CP even Higgs Boson: Ratio of Partial Widths
WWHZH,
WWHWH,
WWHttH,
WWHVBF,
WWHGF,
BR)(
BR)(
BR)(
BR)(
BR)(
W
b
WWW
Z
9 fit parameters:
all rates can
be expressed
by those 9
parameters
H WW chosen as reference as best measured for MH>120 GeV
For 30fb-1 worse by factor 1.5 to 2
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 23 / 45
Total Decay Width H
for MH>200 GeV, tot>1GeV measurement from peak width in ZZ4 l
for MH<200 GeV, tot<< mass resolution no direct determination
upper limit needs input from theory:
mild assumption: gV<gVSM
valid in models with only Higgs doublets and singlets
rate(VBF, HWW) ~ V2 / tot < (V
2 in SM)/ tot
tot< rate/(V2 in SM)
lower limit from rate measurements: tot > W+Z+t+g+....
have to use indirect constraints on tot
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 24 / 45
Fit of couplings with gV < gVSM constraint
8 fit parameters:
coupling to W, Z, , b, t
inv for undetactable decays
e.g. c, gluons,newphoton (new), gluon (new):
non SM contribution to loopsg/g = ½ g2)/g2
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 25 / 45
ILCILCECM: 90 GeV bis 800++ GeV
5 Bunch Trains/s tbunch=337 ns 950 µs 199 ms 950 µs
2820 bunches
Lumi.: 3.4 to 5 x 1034cm-2s-1 (6000xLEP)
L = 500 fb-1 @ 500 GeV ~ 2 to 3 years
L = 1000 fb-1 @ 800 GeV ~ 3 to 4 years
Polarisation: 80% electrons, 60% positrons
No hardware trigger deadtime free
contineous readout for bunch train
Superconducting cavities
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 26 / 45
SM Higgs Boson Production at ILC
17 Higgs events per hour
ECM=500 GeV, MH=120 GeV
Higgs factory
Higgs-Strahlung WW-Fusion
e+e- qq 330/h e+e- WW 930/h e+e- tt 70/h
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 27 / 45
Strategy for e+e- collider
decay mode independent observation in Higgs-Strahlung
from recoil mass spectrum model independent determination of mass, Spin, CP and coupling to Z boson gHZ
rate measurement in Higgs Strahlung with Hxx: gHZ x BR(Hxx) branching ratios BR(Hxx)
indirect but model independent determination of total width tot
BR(Hxx) + tot partial width x coupling gHx
Yukawa coupling from rate in ttH associated production
need: accelerator with luminosity ILC
highly performing detector
2
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 28 / 45
Performance Requirements
Momentum: Higgs mass,…
(1/p) = 7 x 10-5/GeV (1/10xLEP 1/7xLHC)
Impact parameter : Yukawa couplingsd=510/p(GeV)m (1/3xSLD, 1/2,1/5LHC)
Jet energy: Higgs selfcoupling, ttH
E/E = 0.3/E(GeV) (<1/2xLEP 2/3xLHC)
reconstruction of complex multi jet final states (even 8 or more)
hermeticity down to small angles 5 mrad
Design determined by precision physics, not by radiation hardness or event rate !!!
radiation hardness (almost) no problem compared to LHC
1st layer of vertex detector: 109 n/cm2/yr at TESLA = 0.00001 LHC
time structure of collisions and background vom beamstrahlung
read out speed / granularity
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 29 / 45
Detector Concept (TESLA/Large Detector)
tracking system and both calorimeters inside coil
magnetic field B = 4 Tesla
large gaseous central tracking device
precision vertex detector
instrumented mask for background shielding
no hardware trigger
different bunch separation / background level w.r.t to LHC
other technology options possible at ILC e.g. gaseous tracking
all silicium tracking also studied for ILC
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 30 / 45
Why (1/p) = 7 x 10-5/GeV? Higgs mass meas.
independent of H decay model independent
recoil mass to :
MH, ZH, gZZH, Spin
goal: M<0.1x
(1/p)
< 7x10-5/GeV
efficient supression of background
good resolution for recoil mass
e+e-ZZHX
Higgs-Strahlung
precise measurement of lepton momenta
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 31 / 45
Tracking System
Barrel region:Pixel vertex detector (VTX)Silicon strip tracker (SIT)Time projection chamber (TPC)
Forward region: Silicon Disks (FTD) Forward Tracking Chambers (FCH)(e.g. Strawtubes, Si strips)
Momentum resolution:
TPC only: (1/p) = 2.0 x 10-4 /GeV (1/6 x LEP)
TPC+VTX: (1/p) = 0.7 x 10-4 /GeV (1/9 x LEP)
TPC+VTX+SIT: (1/p) = 0.5 x 10-4 /GeV (below the goal)
E and B field
Efficient and robust track reconstruction, seperately in
TPC: 200 space point + VTX+SIT: 7 space points
global track finding: =98.4% (including background)
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 32 / 45
Mass and Coupling to the Z Boson
~ 5 bis 6%m ~ 100 MeV
ZH ~ gZH2 model independent
determination of gZH
decay mode independent selection of ZH with Z or ee
peak position peak height
fit to spectrum of the recoil mass to leptons
gZH/gZH~ 2-3%
m ~ 40 bis 80 MeV with complete reconstruction of the Higgs decay
500fb-1
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 33 / 45
Why d=510/p(GeV)m? Higgs Yukawa Couplings
efficient ID of b,c and light jets
reconstruction of secondary vtx.
with all tracks M, /, Q
Precise measurement of impact par. do
b: 300 m „state of the art“ c 75 m „challenging“<p> = 1 bis 2 GeV
d = a b/p(GeV)
goal: 5m 10m
LHC: 12m 57m
goal: determination of BR(Hbb, cc, light q+g) with O(%) precision
M
IP
Secundary vtx.
l ~ 8 mm
do .
IP
d= a b/p
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 34 / 45
Vertex detector: concept and expected performance
5 pixel layers R1 = 15 mm (1/2SLD, 1/4LEP,1/3LHC)
pixel size: 20x20m2, Punkt < 3 m
thin: 0.1 % X0 pro Lage (1/4 SLD) read out at ladder ends
no hybrid pixels a la LHC
M
e.g. vertex mass
•LEP-c
Expected resolution: = 4.2 4.0/p(GeV)m
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 35 / 45
Fermionic Branching Ratios
Select ZHqq/ll qq events by kinematic cuts
calculate likelihood for Hbb,cc,gg from
precise measurements of tracks at IP
perform fit of MC likelihood distributions to data
event rates
data =
Hbb backgroundHggHcc
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 36 / 45
( )( )
( ) / ( )
HZ X Z
BR H XHZ H BR Z
Higgs Boson Branching Ratios
Decay Rel.Error
for 500 fb , m=120 GeV-1
TDR study: two independent measurements of
alternative approach: measure fraction of Hxx events within an unbiased sample of HZHll events
disadvantage: smaller event sample
advantage : binomial errors smaller than gaussian errors
(one measurement instead of two)
23%
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 37 / 45
Total Decay Width
Indirect determination for M < 180 GeV:
tot << detector resolution no info in width of mass peak
Idea: use tot = (Hxx) / BR(Hxx)
best precision: W Boson
(HWW): from measurement of cross section of WW fusion
BR(HWW): from Higgs-Strahlung ZH with HWW
needed for determination of
Yukawa couplings to fermions
gf2 ~ ff = BR(Hff) x tot
direct determination from peak width
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 38 / 45
Coupling to W Boson and Total Width
WW fusion process:
b
b
fit to missing mass spectrum:
~ gw2xBR(Hbb)
+ meas. of BR(Hbb) in ZH
model independent determination of gw
gW/gW ~ 3 to 13%
= 6 to 16 %
for MH = 120 to 160 GeV
LHC
+BR (H>WW)
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 39 / 45
Top Quark Yukawa Coupling
gttH/gttH = 7 to 15 %
for mH =120 to 200 GeV
including 5% systematic
uncertainty on BG
small cross section and
„a lot of mass“ in the final state
large ECM = 800 GeV high luminosity L = 1 ab-1
challenging analysis (ANN):
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 40 / 45
Top Quark Coupling:Synergy of LHC and ILC
ILC: measurement of branching ratio BR(Hbb) BR(HWW)
LHC: measurement of rate tth x BR(Hbb)
tth x BR(HWW)
gt x BR(Hxx)
ILC at ??
2
combination of both measurementsmodel independent determination of top quark Yukawa coupling
H
xx
x
x
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 41 / 45
Determination of gt
gt ~ 13 to 17 % (7 to 11%)
combination of
LHC and ILC
assume Born level relation: ~ gt2
synergy of LHC and ILC allows 1st
model independent determination
of top Yuakwa coupling
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 42 / 45
The Higgs Boson Profile from ILC
PDG Booklet 201x ?
Why aim for this precision ?
precise test of the SM
discrimination between SM Higgs sector extensions or alternatives
(SUSY, ED, Little H, TC, …)
E. Gross
10-3
rel. error on Higgs boson couplings
expected accuracy: 1 to 5 %
g/g = ½
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 43 / 45
SM or Extended Higgs Sector e.g. Minimal SUSY ?
LHC: discrimination using
rate measurements from
VBF channels (30fb-1)
R = BR(h WW) BR(h )
300 fb-1
assume Higgs mass well measured no systematic errors considered
compare expected
measurement of R in MSSM
with prediction from SM
for same value of MH
systematic error from lumi,
PDFs, QCD in production cancel
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 44 / 45
SM or Extended Higgs Sector ?
ATLASprel.
300 fb-1
ILC
=|RMSSM-RSM|exp
similar study by Duehrssen et al.:
VBF dominates discrimination
comparison of all couplings
discrimination from profile measurements at 2 level
observation of additional Higgs bosons at LHC and ILC500/800
Markus Schumacher, Higgs Fermion Yukawa Couplings at LHC and ILC, Summer School Dresden 2005 45 / 45
Summary
LHC: discovery over full mass range 110 to 1000 GeV
1st measurements e.g.: mass ~ 0.1%, CP, Spinratios of partial width: W/Z, W/t, W/W/b ~10 to 60 %
absolute couplings only with further theoretical input = 5 to 45% depending on mass and particle
ILC: decay mode independent observation mass, CP, Spin mass determination: ~ 0.04 % total width determinable w/o theoretical assumptions absolute couplings (also 2nd generation) =1 to 5 %
LHC+ILC: 1st model independent determination of top quark coupling from synergy of data: ~15%
Let’s hope for unexpected deviations from the SM at LHC and ILCand also other collider and non collider experiments!