1996/05/28 by D. Indumathi, Wei Zhu · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph #nucl-th
paper · pdf · doi:10.1007/s002880050375
published as Z.Phys. C74 (1997) 119-129 · 27 pages LaTeX, with 7 figures of encapsulated postscript files, to appear in Z. Phys. C
arxiv created 1996/05/28 · openalex publication_date 1997/01/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The dynamical origins of the EMC effect are studied. We conclude that a swelling in size of a bound nucleon as well as nuclear binding plays an important rôle in determining the parton distributions within a bound nucleon. We find that the distortion of nucleon structure functions in nuclei can be simply explained with a few fundamental nuclear parameters. PACS numbers: 13.60.Hb, 24.85.+p, 21.10.Dr The fact that the structure functions of bound and free nucleons are not equal is called the EMC effect [1]. Recent accurate data [2, 3, 4] on nuclear structure functions impels us to reconsider the origin of the EMC effect. In this letter we report that this effect can be explained in a broad kinematical region using the idea of swelling and incorporating binding effects using only a few fundamental nuclear parameters but with a new understanding concerning these concepts. We expound on our ideas as follows. As the first step, we choose a set of parton distributions which can describe the structure functions of the free nucleon in the kinematic region of the EMC effect (where Q 2 ranges from less than 1 GeV 2 to a hundred GeV 2). One such model was proposed by Glück, Reya, and Vogt [5]. The model assumes that there exists a scale Q 2 = µ 2 which separates the perturbative regime (Q 2 ≥ µ 2) from the nonperturbative one (Q 2 < Λ 2). All parton distributions are generated dynamically by evolution from a set of valence-like inputs (of the form Nx α PN,q(x)(1−x) β) at µ 2. For example, in the leading order (LO) approximation with µ 2 = 0.23 GeV 2, the valence (uv, dv), the total sea (S), and gluon (g) input distributions are given to be [5], xu N v (x) = 1.377x0.549 PN,u(x)(1 − x) 3.027, xd N v (x) = 0.328x 0.366 PN,d(x)(1 − x) 3.744, xSN(x) = 2x(u + d) = 2.40x 0.29 PN,S(x)(1 − x) 7.88, xgN(x, ) = 35.8x 2.3 (1 − x) 4.0,