Leptoproduction of vector meson from the small x to the valence region

Some non-trivial features of the QCD-improved parton model relevant to applications on heavy particle production and semi-hard (small-x) processes of interest to collider physics are reviewed. The underlying ideas are illustrated by a simple example. Limitations of the naive parton formula as well as first order corrections and subtractions to it are dis-cussed in a quantitative way. The behavior of parton distribution functions at small x and for heavy quarks are discussed. Recent work on possible impact of unconventional small-x behavior of the parton distributions on small-x physics at SSC and Tevatron are summarized. The Drell-Yan process is found to be particularly sensitive to the small x dependence of parton distributions. Measurements of this process at the Tevatron can provide powerful constraints on the expected rates of semi-hard processes at the SSC.

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Rise of the DIS structure function FL at small x caused by double-logarithmic corrections

Journal of High Energy Physics ◽

10.1007/jhep03(2021)274 ◽

2021 ◽

Vol 2021 (3) ◽

Author(s):

B. I. Ermolaev ◽

S. I. Troyan

Keyword(s):

Structure Function ◽

Present Calculation ◽

Synergic Effect ◽

Logarithmic Approximation ◽

Logarithmic Corrections ◽

Small X

Abstract We present calculation of FL in the double-logarithmic approximation (DLA) and demonstrate that the synergic effect of the factor 1/x from the $$ {\alpha}_s^2 $$ α s 2 -order and the steep x-dependence of the totally resummed double logarithmic contributions of higher orders ensures the power-like rise of FL at small x and arbitrary Q2.

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Exclusive heavy vector meson electroproduction to NLO in collinear factorisation

Journal of High Energy Physics ◽

10.1007/jhep08(2021)150 ◽

2021 ◽

Vol 2021 (8) ◽

Author(s):

C. A. Flett ◽

J. A. Gracey ◽

S. P. Jones ◽

T. Teubner

Keyword(s):

Phase Space ◽

Vector Meson ◽

Heavy Quarkonia ◽

Diffractive Scattering ◽

Meson Electroproduction

Abstract We compute the exclusive electroproduction, γ*p → Vp, of heavy quarkonia V to NLO in the collinear factorisation scheme, which has been formally proven for this process. The inclusion of an off-shell virtuality Q2 carried by the photon extends the photoproduction phase space of the exclusive heavy quarkonia observable to electroproduction kinematics. This process is relevant for diffractive scattering at HERA and the upcoming EIC, as well as at the proposed LHeC and FCC.

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