An infinite sequence ∆ = 〈∆n(x0, . . . , xn−1, y, ū) : n < ω〉 of possibly infinite sets of formulas in n + 1 variables x0, . . . , xn−1, y and a possibly infinite system of parameters ū is a parameterized graded deduction-detachment (PGDD) system for a deductive system S over a S-theory T if, for every n < ω and for all φ0, . . . , φn−1, ψ ∈ FmΛ, T, φ0, . . . , φn−1 `S ψ iff T `S ∆n(φ0, . . . ,...

The situation is summarised in Fig. 1, which shows the kinematic regions in the (x,Q) plane covered by (i) the experiments at HERA, (ii) the fixed target deep-inelastic scattering experiments and (iii) the single jet inclusive experiments at the Tevatron. Roughly speaking, the fixed target experiments determine the distributions of the u, d, ū, d̄, s, s̄ quarks for x ∼ 0.1 (and Q ∼ 10 GeV). The H...

The long time behavior for the degenerate Cahn-Hilliard equation [4, 5, 10], ut = ∇ · (1− u)∇ [Θ 2 {ln(1 + u)− ln(1− u)} − αu− 4u ] , is characterized by the growth of domains in which u(x, t) ≈ u±, where u± denote the ”equilibrium phases;” this process is known as coarsening. The degree of coarsening can be quantified in terms of a characteristic length scale, l(t), where l(t) is prescribed vi...

The lepton helicity distributions in the polarized Drell-Yan process at RHIC energy are investigated. For the events with relatively low invariant mass of lepton pair in which the weak interaction is negligible, only the measurement of lepton helicity can prove the antisymmetric part of the hadronic tensor. Therefore it might be interesting to consider the helicity distributions of leptons to o...

Polarized deep inelastic scattering (DIS) data are analyzed in leading and next–to– leading order of QCD within the common ‘standard’ scenario of polarized parton distributions with a flavor–symmetric light sea (antiquark) distribution δq̄, and a completely SU(3)f broken ‘valence’ scenario with totally flavor-asymmetric light sea densities (δū 6= δd̄ 6= δs̄). The latter flavor–broken light sea dis...

We compute the quark and antiquark transversity distributions in the nucleon at a low normalization point (μ≈600MeV) in the large–Nc limit, where the nucleon can be described as a soliton of an effective chiral theory (chiral quark–soliton model). The flavor–nonsinglet distributions, δu(x)−δd(x) and δū(x)−δd̄(x), appear in leading order of the 1/Nc–expansion, while the flavor–singlet distributio...

In connection with the semi-inclusive polarized DIS, it is proposed to consider the first Melin moments ∆q of the polarized quark and antiquark densities, instead of the respective variables δq(x), local in Bjorken x themselves. This gives rise to a very essential simplification of the next to leading order (NLO) QCD and, besides, allows one to use the respective QCD sum rules. An expression fo...

¯ d − ¯ u asymmetry and semi-inclusive production of pions in DIS Abstract We investigate unambiguities in the extraction of the ¯ d − ¯ u asymmetry from semi-inclusive production of pions in DIS. The role of several effects beyond the quark-parton model (QPM) which lead to N π + p = N π + n and N π − p = N π − n and may therefore cloud such an extraction is studied. The results are discussed i...

We prove existence, regularity and a Feynman–Kač representation formula of the strong solution to the free boundary problem arising in the financial problem of the pricing of the American Asian option with arithmetic average. To cite this article: L. Monti, A. Pascucci, C. R. Acad. Sci. Paris, Ser. I 347 (2009). © 2009 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved...

We continue our study of hydrodynamic models of self-organized evolution of agents with singular interaction kernelφ(x) = |x|−(1+α). Following ourworks Shvydkoy and Tadmor (2017) [1,2]which focused on the range 1 ≤ α < 2, and Do et al. (2017) which covered the range 0 < α < 1, in this paper we revisit the latter case and give a short(-er) proof of global in time existence of smooth solutions, t...