2,814 research outputs found
QCD corrections to double J/\psi production in e+e- annihilation at \sqrt{s}=10.6 GeV
Next-to-Leading-Order(NLO) QCD corrections to double J/psi production in
e^+e^- annihilation at sqrt{s}=10.6 GeV are calculated. We find that they
greatly decrease the cross section, with a K factor (NLO/LO) ranging from -0.31
to 0.25 depending on the renormalization scale. Although the renormalization
scale dependence indicates a large uncertainty, when combined with the NLO QCD
corrections to J/psi + eta_c production, it can explain why the double J/psi$
production could not be found at B factories while the J/psi + eta_c production
could, despite the fact that cross section of the former is larger than that of
the latter at LO by a factor of 1.8.Comment: 4 pages, 4 figures, use revtex
QCD corrections to J/psi plus eta_c production in e+e- annihilation at sqrt{s}=10.6 GeV
Next-to-Leading-Order(NLO) QCD corrections to J/jpsi plus eta_c production in
e+e- annihilation at sqrt{s}=10.6 GeV is calculated in this paper, and an
analytic result is obtained. By choosing proper physical parameters, a K factor
(ratio of NLO to LO) of about 2, which is in agreement with the result in
Ref.\cite{Zhang:2005ch}, is obtained. Our results show that the
Next-Next-to-Leading-Order(NNLO) corrections might be quite large. The plot of
the K-factor vs the center-of-mass energy sqrt{s} shows that it is more
difficult to obtain a convergent result from the perturbative QCD without
resummation of ln(s/m_c) terms as the sqrt{s} becomes larger.Comment: 8 pages, 6 figures, two column
Towards a better understanding of the political economy of regional integration in the GMS: Stakeholder coordination and consultation for subregional trade facilitation in China
The main contribution of this paper is the identification of obstacles at the different levels of coordination, and constructive recommendations for (a) improving the effectiveness of existing coordination and (b) forging linkages where necessary between the various stakeholders i.e., central and provincial governments, state-owned enterprises, the private sector – including industrial associations, and small and medium-sized enterprises (SMEs) – border communities, donors and development partners, and civil organizations are the main stakeholders.Political economy, GMS, Trade Facilitation, China
Almost periodic solutions for an asymmetric oscillation
In this paper we study the dynamical behaviour of the differential equation
\begin{equation*} x''+ax^+ -bx^-=f(t), \end{equation*} where
,\ , and are two different positive
constants, is a real analytic almost periodic function. For this
purpose, firstly, we have to establish some variants of the invariant curve
theorem of planar almost periodic mappings, which was proved recently by the
authors (see \cite{Huang}).\ Then we will discuss the existence of almost
periodic solutions and the boundedness of all solutions for the above
asymmetric oscillation.Comment: arXiv admin note: substantial text overlap with arXiv:1606.0893
- …