8,228 research outputs found
Three-dimensional structures of the spatiotemporal nonlinear Schrödinger equation with power-law nonlinearity in PT-symmetric potentials
The spatiotemporal nonlinear Schrödinger equation with power-law nonlinearity in PT-symmetric potentials is investigated, and two families of analytical three-dimensional spatiotemporal structure solutions are obtained. The stability of these solutions is tested by the linear stability analysis and the direct numerical simulation. Results indicate that solutions are stable below some thresholds for the imaginary part of PT-symmetric potentials in the self-focusing medium, while they are always unstable for all parameters in the self-defocusing medium. Moreover, some dynamical properties of these solutions are discussed, such as the phase switch, power and transverse power-flow density. The span of phase switch gradually enlarges with the decrease of the competing parameter k in PT-symmetric potentials. The power and power-flow density are all positive, which implies that the power flow and exchange from the gain toward the loss domains in the PT cell.Funded by the National Natural Science Foundation of China (Grant No. 11375007), the Zhejiang Provincial Natural Science Foundation of China (Grant
No. LY13F050006)
QCD corrections to e^+ e^- to J/\psi(\psi(2S))+\chi_{cJ} (J=0,1,2) at B Factories
We analytically calculate the cross sections of double charmonium production
in (J=0,1,2) at next-to-leading order
(NLO) in in nonrelativistic QCD, and confirm factorization of these
processes. In contrast to production, for which the NLO correction
is large and positive, the NLO corrections for production can be
negative, resulting in decreased factors of 0.91 and 0.78 for J=1 and 2
respectively when . Consequently, the NLO QCD corrections
markedly enlarge the difference between cross sections of and
. This may explain why but
not is observed experimentally.
Moreover, for , the NLO QCD corrections
substantially reduce the dependence and lead to predictions with small
theoretical uncertainties.Comment: Version published in PRD, 6 pages, 3 figures, 2 tables, one reference
adde
J/psi (psi') production at the Tevatron and LHC at O(\alpha_s^4v^4) in nonrelativistic QCD
We present a complete evaluation for \jpsi(\psip) prompt production at the
Tevatron and LHC at next-to-leading order in nonrelativistic QCD, including
color-singlet, color-octet, and higher charmonia feeddown contributions. The
short-distance coefficients of \pj at next-to-leading order are found to be
larger than leading order by more than an order of magnitude but with a minus
sign at high transverse momentum . Two new linear combinations of
color-octet matrix elements are obtained from the CDF data, and used to predict
\jpsi production at the LHC, which agrees with the CMS data. The possibility
of \sa dominance and the \jpsi polarization puzzle are also discussed.Comment: Version published in PRL, 4 pages, 4 figure
- …