منابع مشابه
Comparative analysis of non - perturbative effects in B →
In order to extract the Cabibbo-Kobayashi-Maskawa matrix element |Vub| from B → Xulνl decays, the overwhelming background from B → Xclνl decays must be reduced by appropriate acceptance cuts. We study the non-perturbative effects due to the motion of the b quark inside the B meson on the phenomenologically relevant decay distributions of B → Xulνl in the presence of such cuts in a comparative a...
متن کاملNon - perturbative Effects in B → X s l + l −
The rare decay B → Xsll provides excellent prospects for precision tests of Standard Model flavour dynamics. The process can be computed in perturbation theory with small uncertainty. However, in order to ensure a reliable theoretical prediction, also potentially important effects from non-perturbative QCD have to be controlled with sufficient accuracy. The present article summarizes recent dev...
متن کاملNon - Perturbative Strings Effects
Computations of non-perturbative contributions is still a difficult task. In (supersymmetric) Field theory a direct computation requires the construction of the measure of integration over vacua containing n-instantons, which is not yet available for every n. The use of dualities is still the main tool for getting the answer. In String theory the D-instantons contributions for the R4 were conje...
متن کاملPerturbative and Non-perturbative Corrections to B → Dlν
The ratios R+, R1, and RA are defined at zero recoil; the ratio R− is defined in the limit of zero recoil. The ρ are matching factors, needed to patch radiative corrections from short distances. The ratios R+ and R− directly give the form factors h+ and h−, which together form the hadronic amplitude for B → Dlν. Information from R+, R1, and RA must be extracted from their heavy quark expansions...
متن کاملNon-perturbative effects in spin glasses
We present a numerical study of an Ising spin glass with hierarchical interactions--the hierarchical Edwards-Anderson model with an external magnetic field (HEA). We study the model with Monte Carlo (MC) simulations in the mean-field (MF) and non-mean-field (NMF) regions corresponding to d ≥ 4 and d < 4 for the d-dimensional ferromagnetic Ising model respectively. We compare the MC results with...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nuclear Physics B - Proceedings Supplements
سال: 1999
ISSN: 0920-5632
DOI: 10.1016/s0920-5632(99)00174-7