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Deep Elastic Processes of Composite Particles in Field Theory and Asymptotic Freedom

High Energy Physics - Phenomenology · Submitted 20 Oct 2004 · 31 references

Pith's verdict: The 1977 preprint that first defines the pion distribution amplitude and writes the leading-twist pion form factor as a DA convolution; the central formula holds, and only the low-Q² numerical illustration is soft.

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arXiv IDhep-ph/0410276 (version 1)
Pith IDAWHUP42V, Pith's permanent record of this paper and its review
CitationA.V. Radyushkin. "Deep Elastic Processes of Composite Particles in Field Theory and Asymptotic Freedom." arXiv:hep-ph/0410276 (2004). https://pith.science/paper/AWHUP42V
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The paper

The paper claims

The pion's electromagnetic form factor at large momentum transfer is claimed to factor into a hard, calculable quark-scattering amplitude convolved with a universal pion distribution amplitude, whose overall normalization is fixed by the早已

The reading

This paper asks whether a bound state's internal structure can be separated cleanly from the short-distance physics of a hard collision, using the pion's electromagnetic form factor as the test case. The author argues that at large momentum transfer $Q^2$ the answer is yes: the form factor becomes a convolution of two copies of a single universal object, the pion distribution amplitude, with a hard amplitude computed order by order in perturbative QCD. The distribution amplitude is defined through the moments of twist-2 axial quark operators, so its shape is a property of the pion alone and its overall normalization is fixed by the measured pion decay constant $f_$ rather than fitted. The payoff is a parameter-free prediction, $F_$. The paper also sketches the same logic for the proton and for wide-angle two-body scattering, where it reproduces the quark counting rules plus an extra logarithm from the running coupling.
Original abstract

This is an English translation of my 1977 Russian preprint. It contains the first explicit definition of the pion distribution amplitude (DA), the expression for the pion form factor asymptotics in terms of the pion DA, and formulates the pQCD parton picture for hard exclusive processes. Abstract of the original paper: The large Q^2 behavior of the pion electromagnetic form factor is explicitly calculated in the non-Abelian gauge theory to demonstrate a field-theoretical approach to the deep elastic processes of composite particles. The approach is equivalent to a new type of parton model.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 3,595 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.83 · states limitation 0.08 · human participants 0.01 · controlled comparison 0.02 · randomized assignment 0.01 · states quantitative result 0.10 · compares with prior results 0.15 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; .

This is an English translation of my 1977 Russian preprint. It contains the first explicit definition of the pion distribution amplitude (DA), the expression for the pion form factor asymptotics in terms of the pion DA, and formulates the pQCD parton picture for hard exclusive processes. Abstract of the original paper: The large Q^2 behavior of the pion electromagnetic form factor is explicitly calculated in the non-Abelian gauge theory to demonstrate a field-theoretical approach to the deep elastic processes of composite particles. The approach is equivalent to a new type of parton model.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#sentencerolethe authors' own workstates the main conclusionstrength
s0 This is an English translation of my 1977 Russian preprint. background 0.99 0.17 0.02 asserted 1.00
s1 It contains the first explicit definition of the pion distribution amplitude (DA), the expression for the pion form factor asymptotics in terms of the pion DA, and formulates the pQCD parton picture for hard exclusive processes. contribution 0.99 0.83 0.24 asserted 1.00
s2 Abstract of the original paper: The large Q^2 behavior of the pion electromagnetic form factor is explicitly calculated in the non-Abelian gauge theory to demonstrate a field-theoretical approach to the deep elastic processes of composite particles. contribution 0.64 0.87 0.66 asserted 1.00
s3 The approach is equivalent to a new type of parton model. interpretation 1.00 0.50 0.13 asserted 1.00

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 1.00.

What was examined, and what was not

sources read
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  • figures and tables
  • references and citing sentences
  • relations to other papers
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not run
  • S sections
  • T body sentences
  • C citations
  • R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

Figures
Figure 1. Electromagnetic form factor of a composite pion.
Figure 2. Subgraph producing the leading large-Q2 contribution. The functions f, ¯f do not depend on J because the contraction of V into point eliminates the dependence on Q2 . Summation over all possible subgraphs looks like a perturbative series, with E(Q2/µ2 , g(µ 2 )) describing short-distance interactions while f and ¯f correspond to the properly normalized quark-pion vertices: Fπ(Q 2 ) = 1 Q2 X∞ n=0 X∞ m=0 ¯f I m(µ 2 , g, P′ )E IK mn(Q 2 /µ2 , g)f K n (µ 2 , g, P) , (3) where I, K denote the spinor indices. The leading contribution can be obtained only when f and
Figure 3. Structure of the lowest-order diagram. Integration in the neighboorhod of α ∼ 0, β ∼ 0 gives g 2C2(R) 2P µ q 2 X VL,VR  g 2 16π 2 NL+NR Z Q dα(L) D2(VL) e iI(α (L) σ ,m2 π) 1 − L−/D(VL) G A(VL) Z Q dα(R) σ D2(VR) e iI(α (R) ,m2 π) 1 − R−/D(VR) G A(VR) . (8) We used the fact that for the diagrams of Fig. 3b type R+ = D(VR), where R± = R′ ± R, and hence R/D(VR) = (1 − R−/D(VR))/2. Expanding into series 1/(1 − R−/D(VR)) = P(R−/D) n we obtain an expression of Eq. (3) type. The factor (R−/D) n just means that the corresponding operator contains n derivatives. Due to symmetry between R…

Figures reproduced from arXiv:hep-ph/0410276 by the authors.

References
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45 arXiv papers cite this in 62 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 24 sentences without a confident label

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