federico mescia (ryc) outline: a. introduction b. our present world picture: standard model c. the...
Post on 19-Dec-2015
213 views
TRANSCRIPT
Federico Mescia (RyC)
Outline:
a. Introduction
b. Our present world picture: Standard Model
c. the future challenge:
(Flavour Physics in the LHC era)
ECM & ICC, Universitat de Barcelona
IX Jornada Cientifica d’ECM, February 7th, 2009
Particle Physics at ECM: Phenomenology
my research activity ECM
Federico Mescia
(Flavour Physics in the LHC era)
room 6.15, tel 39195
Particle Physics at ECM: Phenomenology
IX Jornada Cientifica d’ECM, February 7th, 2009
•Once Upon a Time ~ 2000 yrs ago
• Introduction
an economical description, consistent to our “daily” observation;
at higher energy scale <-> at shorter distances, new phenomena come up and new degrees of freedom are needed!
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
• Dep. d’Estructura i Constituents de la Materia about ~ 2000 years ago:
•Once Upon a Time ~ 2000 yrs ago
• Introduction
• Dep. d’Estructura i Constituents de la Materia about ~ 2000 years ago:
an economical description, consistent to our “daily” observation;
at higher energy scale <-> at shorter distances, new phenomena come up and new degrees of freedom are needed!
Modern Language: example of effective theory valid at at our day-life scale:
at the given scale, d.o.f looks fundamental! at higher scale, d.o.f only eff. variables (vevs)
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
macroscopic v.microscopic v.
f
What is a Dep. d’Estructura i Constituents de la Materia about?
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
40 orders of magnitude of research activities
Particle P. Nuclear P. Solide P Biology Astrophysics Cosmology
a few constituents, and many structures at the various scales,
m
• Introduction:
f
What is a Dep. d’Estructura i Constituents de la Materia about?
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
Particle P. Nuclear P. Solide P Biology Astrophysics Cosmology
m
My research line
• Introduction:
40 orders of magnitude of research activities
f
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
Particle P. Nuclear P. Solide P Biology Astrophysics Cosmology
m
My research linePhenomenology at ECM
Theory: Concha, Domenec, Joan, Joan, Sasha, (Jaume)Lhcb:Lluís, Eugeni, Graciano, Hugo, Ricardo, (David)
• Introduction:
40 orders of magnitude of research activities
f
• Introduction:
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
Particle P. Nuclear P. Solide P Biology Astrophysics Cosmology
m
My research lineoverlap with Lattice QCD studies
from Assumpta & Àngels, Volodymyr
40 orders of magnitude of research activities
• The present picture: Standard Model (forces and constituents)
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
6 types of quarks and lepton
Our Modern Mendeleev’ Table
Type of forces:
(gravity) strong (QCD) weak em (QED)
SM
strong= large at low energy
ew= 1/137 small
• Flavour Physics:
Flavour Transitions: Weak interactions violate flavour: CKM matrix and CP violation
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
bc
W
VCKM
in
...
CKt LL
M bc V W L
CKMV
=>3 angles and 1 Phase
• Flavour Physics:
Flavour Transitions: Weak interactions violate flavour: CKM matrix and CP violation
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
macroscopic picture(effective couplings after ewsb)
bc
W
VCKM
in
...
CKt LL
M bc V W L
• Flavour Physics: as probe of new fundamental interactions
Flavour Transitions: Weak interactions violate flavour: CKM matrix and CP violation
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
bc
W
VCKM
microscopic picture?=>LHC job
(the ewsb mechanism?)
2 open options: Linear or Non-Linear Higgs realisation?
THDM SUSY
Techni C Little H. Extra D.
in
...
CKt LL
M bc V W L
• Flavour Physics: as probe of new fundamental interactions
Flavour Transitions: Weak interactions violate flavour: CKM matrix and CP violation
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
bc
W
VCKM
microscopic picture?
• ad hoc description in the SM
1. not stable; 2.not fully investigated
(D )D
ewsb sector
H H V H H
ijL R
flavour sector
cY h.H
in
...
CKt LL
M bc V W L
• Future Challenge:
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
But already many exp. But already many exp. hints for physics hints for physics Beyond SMBeyond SM ::
gravity UV ~ 1016 TeV neutrino physics UV ~ 109 TeV (see-saw-leptog.) relic density WIMP 1 TeV, strong 1 TeV? matter/anti-matter asymmetries
and one big mystery left-over:and one big mystery left-over: THE ORIGIN OF THE MASS? HIGGS MECANISMTHE ORIGIN OF THE MASS? HIGGS MECANISM
1TeV
MZ
SM
MPlanck
109 TeV
Naturalness of Higgs sector would require n.o.f 1 TeV
The SM successfully describes phenomena to the Fermi scale, ~ 0.1 TeV => 10-17 m
Direct searches
Atlas and CMS;
indirect searches
MEG, LHCb, NA62;
Lepton, B, & K decays
to discover new particles at 1TeV to study flavour symmetries of n.d.f
Two main ways to unravel the naturalness of the Higgs sector
• Future Challenge: the origin of the Mass? the origin of the Mass?
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
1TeV
MZ
SM
MPlanck
109 TeV
Phenomenology of Quark Flavour Transitions
=>weak hadron decays in the SM and =>weak hadron decays in the SM and BSMBSM
• My research Activity:
strong= large at low energy.(non-perturbative method)
theoretical predictions plagued by hadronic uncertainties
KK KK xxs
L
˜ dR˜g̃
s
L
˜dR˜ g̃
Standard Model New Physics
Lattice QCDLattice QCD
K=sd
PhenomenologyPhenomenology
• Although no ``ab initio’’ limitations on the approach, limitations in computing resources introduce some approximations:
source of systematic errors.
Lattice QCDLattice QCD
lattice spacing a
lattice size L
quark field
gauge field
• Physical Quantities are computable from first principles, by tuning only the parameters appearing in the QCD Lagrangian, namely mq and s
• Green Functions => integrals of gauge and quark fields on a finite and discrete Box:
(x1) (x2) (x3) ∫ [d] (x1) (x2) (x3) e-S()
Studies with unquenched and light quark masses are now reliable, thanks to recent developments in both recent developments in both algorithms and new lattice actions.algorithms and new lattice actions.
Old-2001new
Time scalingTime scaling
QUENCHED QCD NF=0
seaqm
• Wilson: Luscher et al.-’05, m~280 MeV (NF=2)
• Twisted-mass: Boucaud et al.-‘06, m~280->250 MeV (NF=2 -> NF=2+1+1 ) • Clover: Lellouch et al.-’07, m~210 MEV (NF=2+1)
• Clover: PACS-CS-’07, m~190 MEV (NF=2+1)
• DomainWall: RBC-’07, m~300 MEV (NF=2+1)
• Staggered: MILC-2002, m~240 MeV ( NF=2+1 advanced studies)
Recent outstanding achievementsRecent outstanding achievements::Recent outstanding achievementsRecent outstanding achievements::
NF=2+1 ms + mu=md
seacm
The Wilson formulation of the lattice QCD action (standard up to 2002) did not allow to get m< 500 MeV**
**(physical m= 137 MeV)
The theoretical calculation can be performed only numerically.
In order to achieve the required precision, about 1 billion of billions operations are necessary, corresponding to an integral over 50 millions degrees of freedom and to the inversion of
thousands of matrices with 100 millions of elements
Parallel super-computer (~1 Tflop)
MareNostrum
DETERMINATIONS of the CKM couplings ρ-η DETERMINATIONS of the CKM couplings ρ-η
LATTICE QCD calculations has allowed to reduce the relative hadronic uncertainty!
in L LtCKMU D WV
L
DETERMINATIONS of the CKM couplings ρ-η DETERMINATIONS of the CKM couplings ρ-η
LATTICE QCD calculations has allowed to reduce the relative hadronic uncertainty!
in L LtCKMU D WV
LMy contribution
ECM on lattice QCDECM on lattice QCD
QCD potential
QCD coupling const
Flavor physics
Nuclear Physics
Phase transition
Dynamical fermions
Assumpta
Joan
Domenec
MareNostrum
Nature is a funny mess!Nature is a funny mess!
• Conclusion
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
Nature is a funny mess!Nature is a funny mess!
• unravelling mechanism of nature involves many unravelling mechanism of nature involves many different research lines,different research lines,
• and a lot of expertiseand a lot of expertise Dep. ECMDep. ECM
glad to be hereglad to be here
• Conclusion
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
PhenomenologyPhenomenology
Potential n.d.f at the TeV scale must have a rather sophisticated flavour structure … which we have not clearly understood yet
NEW Physics
flavour facilities
Rare K decays:
• e.w loopse.w loops• highest CKM suppressionhighest CKM suppression• S=1 couplingS=1 coupling like like ’’ • very cleanvery clean like like sin2sin2
LFV
• zero in the SM
Lepton Universalityin K and B B rare Decays
Bd,sSM tree-level contribution SM tree-level contribution accessible to very high accessible to very high precisionprecision
BuBu
an appealing scenario is MFV at large tanHu< Hd>
Barenboim et al, ‘07
Present Constraints from Flavour Physics!high discriminating powers to specific Higgs sector extension
wide bibliography for each constraints in the plots
an appealing scenario is MFV at large tanHu< Hd>
potential discovery modes from potential discovery modes from LHcbLHcb to to SuperBSuperB
B+ Bd,s l+l-
B+ D
K+
CC FCNC
FCNC amplitudes
c u u
BdsDv Buv KuvH+
exchange
Helicity suppressed
decays
Observables within 15% of theoretical uncertainties
ANTIMATTER
MATTER quarks
electron neutrino leptons
ANTIMATTER antiquarks positron antineutrinoantileptons
(visible) MATTER qqq proton BARYONS
ANTIMATTER qqq antiprotonANTIBARYONS
MESONS qq
strong= large at low energy~1GeV.
Direct searches
Atlas and CMS;
indirect searches
MEG, LHCb, NA62;
Lepton, B, & K decays
to discover new particles at 1TeV to study flavour symmetries of n.d.f
• Future Challenge: the origin of Mass? the origin of Mass?
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
THEORY EXPERIMENTTHEORY EXPERIMENT (QCD confined)(QCD confined)
•Once Upon a Time ~ 2000 yrs ago an economical description, consistent
to our “daily” observation;
at higher energy scale <-> at shorter distances, new phenomena come up and new degrees of freedom are needed!
Federico Mescia:”Particle Physics Phenomenology” ECM room 6.15, tel 39195
Since then, better “effective” theories have been designed for the different regime of
Nature
• Introduction
• Dep. d’Estructura i Constituents de la Materia about ~ 2000 years ago: