1,720,969 research outputs found
Asymmetries involving dihadron fragmentation functions: from DIS to e+e- annihilation
No full textUsing a model calculation of dihadron fragmentation functions, we fit the spin asymmetry recently extracted by HERMES for the semi-inclusive pion pair production in deep-inelastic scattering on a transversely polarized proton target. By evolving the obtained dihadron fragmentation functions, we make predictions for the correlation of the angular distributions of two pion pairs produced in electron-positron annihilations at BELLE kinematics. Our study shows that the combination of two-hadron inclusive deep-inelastic scattering and electron-positron annihilation measurements can provide a valid alternative to Collins effect for the extraction of the quark transversity distribution in the nucleon
Scale evolution of kt-distributions
No full textWe review some of the features of the evolutions equations for transverse momentum dependent parton distributions recently proposed by us. We briefly describe the new ingredients entering the equations and their relationship with ordinary evolution equations. We comment on possible choices for the initial conditions and then show results for the evolved distributions obtained by numerical implementation of the equations. By computing the average transverse momentum at different scale we highlight some general properties of the solutions. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.SCOPUS: cp.pinfo:eu-repo/semantics/publishe
Studies of Backward Particle Production with a Fixed-Target Experiment Using the LHC Beams
Full text linkThe foreseen capability to cover the far backward region at a Fixed-Target Experiment using the LHC beams allows one to explore the dynamics of the target fragmentation in hadronic collisions. In this report we briefly outline the required theoretical framework and discuss a number of studies of forward and backward particle production. By comparing this knowledge with the one accumulated in Deep Inelastic Scattering on target fragmentation, the basic concept of QCD factorisation could be investigated in detail
QCD analysis of forward neutron production in DIS
No full textWe consider forward neutron production in DIS within fracture functions formalism. By performing a QCD analysis of available data we extract proton-to-neutron fracture functions exploiting a method which is in close relation with the factorisation theorem for this class of processes
Associated production of one particle and a Drell-Yan pair
No full textWe briefly discuss the collinear factorization formula for the associated production of one particle and a Drell-Yan pair in hadronic collisions. We outline possible applications of the results to three different research areas. © 2010 Elsevier B.V.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Associated production of one particle and a Drell-Yan pair in hadronic collisions
Full text linkpeer reviewedWe propose a collinear factorization formula for the associated production of one particle and a Drell-Yan pair in hadronic collisions. It is shown that additional collinear singularities appearing in the next-to-leading order calculations that cannot be factorized into parton and fragmentation functions are systematically renormalized by introducing fracture functions. Next-to-leading order coefficient functions for cross-sections double differential in the fractional energy of the identified hadron and lepton pair invariant mass are presented
Single-diffractive Drell–Yan pair production at the LHC
Full text linkWe present predictions for single-diffractive low-mass Drell–Yan pair production in pp collisions at the LHC at TeV. Predictions are obtained adopting a factorised form for the relevant cross sections and are based on a new set of diffractive parton distributions resulting from the QCD analysis of combined HERA leading proton data. We discuss a number of observables useful to characterise the expected factorisation breaking effects
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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