Download - fermion and sfermion masses
fermion and sfermion massesfermion and sfermion masses
Melina Gómez Bock
Mini-Workshop on flavor physics: Mexican taste 24-25 November 2008
...el sabor leptónico nació con el descubrimiento del muón y la famosa pregunta de I.I. Rabi: ¿ quién ordenó esto? [W. Marciano:97]
flavor history
Una vez que Gell-Mann y yo ibamos camino a un restaurant en Pasadena para comer, pasamos por un lugar de helados Baskin & Robins, donde anunciaban 32 sabores diferentes. De repente, a Murray se le ocurri¶o una propuesta para usar el término “sabor" (...) para distinguir entre los diferentes grados de libertad de los quarks.[Fritzsch:01]
contentscontents
SUSY
Flavor in SUSY
Sfermions masses
Radiative generation of lepton masses
Flavor violation processes
x
1019GeV Planck Scale
GU
1GeV = 1.2 13 K
10-33cm10-44s
EM
StandardModel
EW
weak
246 MeV
SUSY
t
E
strong gravity
CPVFV FCNC
bosonsfermions
SusyQ
Q | > = | >
Q | > = | >
Chiral supermultipletChiral supermultiplet
Fermión de Weyl
Campo escalar complejo
Flavor in SUSYFlavor in SUSY
Sfermion mass matrixSfermion mass matrix
General contributions to sfermion massGeneral contributions to sfermion mass
From Soft SUSY breaking terms Direct contribution to sfermion masses
Contribution through Higgs interaction
Trilineal scalar couplingsTrilineal scalar couplingsOff-diagonal mass terms
trilineal mass terms
Mass contribution from auxiliary field FMass contribution from auxiliary field F
Mass contribution from auxiliary field DMass contribution from auxiliary field D
sfermion massessfermion masses
A
Trilineal terms
degenerationdegeneration, where different sfermion families have the same mass;
proportionalityproportionality, here the trilinear A-terms are proportional to the Yukawa couplings (SUGRA)[Hall:86] ;
decouplingdecoupling, where the superpartners are too heavy to affect the low energy physics(Split SUSY, focus point SUSY, inverted hierarchy)[Feng:05];
alignmentalignment, in this case the same physics that plains the fermion mass spectra and mixing angles also would explain the pattern of sfermions mass spectra [Nir:1993]
Several conditions or scenarios have been proposed , which reduce the number of free parameters and safely fit the experimental restrictions.
Trilineal term Ansatz
1.We have a defined mixing angle for sfermions2.Analitic expresions for FV processes3.We have no dependence on renormalization scale Q4.We are able to compare with low scale data5.Bound the parameter space of the model6.We have expresions for mass values of different sfermions -> non-universality
advantages:
LO mass matrix
Sfermion massesSfermion masses
Radiative generation of leptons masses
1 1 2 21 ( )2
f ffM vY v Y
Radiative generation of leptons masses
Flavor violation
if~
jf~
if jfB
Flavor violation in leptons
sabor!!!!
h0
h0
Hierarchy problem