16 research outputs found
Anomalies in Weak Decays of Hadrons Containing a b Quark
No full textA brief review of the current state of observed deviations of theoretical
predictions from experimental data in semileptonic decays of and
mesons is given. A theoretical analysis of these decays is carried out, taking
into account the effects of new physics, which appear due to the introduction
of new four-fermion operators, which are absent in the basis of the Standard
Model (SM) operators. The necessary form factors are calculated within the
framework of the covariant quark model developed in our papers.Comment: Contribution to: International Conference on Quantum Field Theory,
High-Energy Physics, and Cosmolog
Non-Leptonic Two-Body Decays of Charmed Mesons and CP Violation
No full textThe nonleptonic two body decays of the and mesons represent a key subject to study possible effects of CP violation. The attention for these decay modes was triggered four years ago by the results of measurements of the difference between CP asymmetries in charged and final state, . Although the measured is now compatible with zero the nonleptonic decays of charmed mesons into a pair of light mesons is an interesting subject for many reasons. Here we discuss phenomenological models to study the decays into two pseudoscalar mesons
Determination of the neutron / gamma separation threshold on single crystals of stilbene
No full textSection V. Equipment, Methods and Automation of Nuclear Experiments, Interaction of Nuclear Radiation with the Matter and Applications of Methods of Nuclear Physic
The study of b-s anomaly decays in covariant quark model
No full textThe work is devoted to the study of b-s anomaly decays. We compute the relevant form factors in the framework of the covariant quark model with infrared confinement in the full kinematical momentum transfer region. The calculated form factors are used to evaluate branching fractions and polarization observables in the decay caused by the presence of the intermediate scalar and in the cascade decay . We compare the obtained results with available experimental data and the results from other theoretical approaches
Semileptonic decays of <i>B</i><sub><i>c</i></sub> mesons into charmonium states
No full textIn this work we study the semileptonic decays of Bc meson. We evaluated
Bc→ D
D
*
,
B
c
→
D
s
D
s
*
and
Bc→ηc→
J
/
ψ
transitions form factors in the full kinematical region within the covariant quark model. The calculated form factors are used to evaluate the semileptonic decays of Bc meson and it was defined ratios (Rηc , RJ/ψ, RD ,RD*) of the branching ratios, which will be hopefully tested on LHC experiments.We compare the obtained results with the results from other theoretical approaches
Semileptonic decays of Bc mesons into charmonium states
No full textIn this work we study the semileptonic decays of Bc meson. We evaluated
Bc→ D
D
*
,
B
c
→
D
s
D
s
*
and
Bc→ηc→
J
/
ψ
transitions form factors in the full kinematical region within the covariant quark model. The calculated form factors are used to evaluate the semileptonic decays of Bc meson and it was defined ratios (Rηc , RJ/ψ, RD ,RD*) of the branching ratios, which will be hopefully tested on LHC experiments.We compare the obtained results with the results from other theoretical approaches
A realistic photon spectra in polarized γ γ processes in SANCphot
No full textAbstract This work presents an approach to improve the precision of polarized photon–photon collisions simulation implemented in the SANCphot package. The basic linear Compton approximation of the incoming photon spectrum is extended to a general energy distribution and a realistic description of circular or linear polarizations as expected to be seen at photon–photon colliders
Two-loop QED/QCD corrections for polarized process in SANCphot
No full textThe new version of the SANCphot integrator has been prepared for fast and stable numerical calculations up to two loops for polarized light-by-light scattering. One-loop modules based on the helicity formalism with massive particles and two-loop modules with massless particles inside the loops are used. The presented study is driven by the potential of polarized photon beams to probe the high energy region. This study is a contribution to the research program of the CEPC project being under development in China
Study of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>B</mml:mi></mml:mrow><mml:mrow><mml:mi>c</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math> decays into charmonia and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>D</mml:mi></mml:math> mesons
No full textRare
No full textIn this article, we study the rare decays corresponding to transition in the framework of the covariant confined quark model. The transition form factors for the channels and are computed in the entire dynamical range of momentum transfer squared. Using the form factors, we compute the branching fractions of the rare decays and our results are found to be matching well with the experimental data. We also compute the ratios of the branching fractions of the to rare decays using the inputs from previous papers on using this model. Further, using the form factors, model dependent and independent parameters, we also compute different other physical observables such as forward backward asymmetry, longitudinal polarization and angular observables in the entire range as well as in bins [0.1–0.98] GeV and [1.1–6] GeV. We also compare our findings with different theoretical predictions
