327 research outputs found
Muon g-2, rare decays P \to l^+l^- and transition form factors P \to \gamma\gamma^*
Measuring the muon anomalous magnetic moment g-2 and the rare decays of light
pseudoscalar mesons into lepton pair P \to l+l- serve as important test of the
standard model. To reduce the theoretical uncertainty in the standard model
predictions the data on the transition form factors of light pseudoscalar
mesons play significant role. Recently new data on behavior of these form
factors at large momentum transfer was supplied by the BABAR collaboration. We
comment on the (in)consistency of these data with perturbative QCD expectation.Comment: 4 pages, 3 figures, invited talk at the 3rd Joint International
Hadron Structure'09 Conference, Tatranska Strba (Slovak Republic), Aug.
30--Sept. 3, 2009; v2 - some typos are correcte
Nonlinear analysis of RR and QT variability for cosmonauts data
Nonlinear analysis of cardiovascular oscillations gives important information about their autonomic regulations. New nonlinear tools like Mindexes gives possibility to analyze the most pure dynamic
process that are observed by RR and QT intervals variability. Time series classification that is based on Mindexes
allows using stationary methods of oscillation variability like Fourier analysis for sure
Stability analysis of RR and QT variability for cosmonauts data
Stability analysis of cardiovascular oscillations together with nonlinear nalysis gives important and complements information about their autonomic regulations. New nonlinear tools like M-indexes gives
possibility to analyze stability of the most pure dynamic process that is observed with the help of RR and QT intervals variability
Search for decay at Super factory
A Monte Carlo study of possible background processes in a search for decay has been performed for conditions of the Super
factory (CTF) (at a center-of-mass energy 3.686 GeV, 3.77 GeV and 4.17 GeV).
The background from events has been analysed. Selection
criteria for background suppression are suggested and necessary requirements on
the detector characteristics have been found. The CTF can successfully compete
with the Super B-factory in a search for decay.Comment: 3 pages, 1 figures; contribution to the Proceedings of the PHIPSI11
Workshop (Novosibirsk, Russia, 19-22 September 2011
CP Tagged Decays at SuperBaBar
We explore the possibility of measuring the CKM parameter gamma using CP
tagged decays at a very high luminosity e+e- B Factory. A new collider capable
of integrating as much as 10 inverse attobarns per year is being discussed as a
possible future for SLAC beyond the current PEP-II program, and could also be
in the future of KEK. In two years of operation, it could be possible for a
successor to BaBar or Belle to accumulate a sample of one million CP tagged B
decays. We find that a theoretically clean extraction of gamma with uncertainty
less than 5 degrees may be achievable in the analysis of such a data set.Comment: 14 pages, 4 figures; minimal revisions for version to appear in
Physical Review D, all formulas and conclusions unchange
Model analysis of the world data on the pion transition form factor
We discuss the impact of recent Belle data on our description of the pion
transition form factor based on the assumption that a perturbative formalism
and a nonperturbative one can be matched in a physically acceptable manner at a
certain hadronic scale . We discuss the implications of the different
parameters of the model in comparing with world data and conclude that within
experimental errors our description remains valid. Thus we can assert that the
low nonperturbative description together with an additional term
at the matching scale have a strong influence on the behavior up to very
high values of .Comment: 6 pages and 3 figures. Contains a comparison with other models and
additional reference
Pseudoscalar meson form factors and decays
In this communication we discuss few topics related with modern experimental
data on the physics of light pseudoscalar mesons. It includes the contribution
of the pseudoscalar mesons to the muon anomalous magnetic moment (AMM), ,
the rare decays of light pseudoscalar mesons to lepton pair, the transition
form factors of pseudoscalar mesons at large momentum transfer, the pion
transversity form factor.
Measuring the muon anomalous magnetic moment and the rare decays of
light pseudoscalar mesons into lepton pair serve as
important test of the standard model. To reduce the theoretical uncertainty in
the standard model predictions the data on the transition form factors of light
pseudoscalar mesons play significant role. Recently new data on behavior of
these form factors at large momentum transfer was supplied by the BABAR
collaboration. Within the nonlocal chiral quark model it shown how to describe
these data and how the meson distribution amplitude evolves as a function of
the dynamical quark masses and meson masses.Comment: 14 pages, 7 figures, based on the talks given at Hadron Structure 11
(Slovakia, Tatransk\'a \v{S}trba, June 27th - July 1st, 2011), The Actual
Problems of Microworld Physics (Gomel, Belarus, August 1 - 12, 2011),
International Workshop on e+e- collisions from Phi to Psi (Novosibirsk,
Russia, September 19-22, 2011
Probing scalar particle and unparticle couplings in e+ e- -> t tbar with transversely polarized beams
In searching for indications of new physics scalar particle and unparticle
couplings in e^+ e^- \to t\bar t, we consider the role of transversely
polarized initial beams at e^+ e^- colliders. By using a general relativistic
spin density matrix formalism for describing the particles spin states, we find
analytical expressions for the squared amplitude of the process with t or \bar
t polarization measured, including the anomalous coupling contributions. Thanks
to the transversely polarized initial beams these contributions are first order
anomalous coupling corrections to the Standard Model (SM) contributions. We
present and analyse the main features of the SM and anomalous coupling
contributions. We show how differences between SM and anomalous coupling
contributions provide means to search for anomalous coupling manifestations at
future e^+ e^- linear colliders.Comment: 28 pages in LaTeX, including 7 encapsulated PostScript figures,
published versio
Possibility of extracting the weak phase from decays
We explore the possibility of extracting the weak phase from pure
tree decays in a model
independent way. The CP violating weak phase can be determined
cleanly, without any hadronic uncertainties, as these decay modes are free from
the penguin pollutions. Furthermore, neither tagging nor time dependent studies
are required to extract the angle with these modes.Comment: 12 pages, LaTex, Minor changes in the text, version to appear in
Phys. Rev.
Chiral doublers of heavy-light baryons
We discuss the consequences of the chiral doubling scenario for baryons built
of heavy and light quarks. In particular, we use the soliton description for
baryons, demonstrating why each heavy-light baryon should be accompanied by the
opposite parity partner. Our argumentation holds both for ordinary baryons and
for exotic heavy pentaquarks which are required by the symmetries of QCD to
appear in parity doublets, seperated by the mass shift of the chiral origin.
Interpreting the recently observed by BaBaR, CLEO and Belle charmed mesons with
assignment as the chiral partners of known and mesons,
allows us to estimate the parameters of the mesonic effective lagrangian, and
in consequence, estimate the masses of ground states and excited states of both
parities. In particular, we interpret the state recently reported by the H1
experiment at HERA as a chiral partner of yet
undiscovered ground state pentaquark .Comment: 10 pages, in v2 some typos corrected, references adde
- …