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Title: QCD compositeness as revealed in exclusive vector boson reactions through double-photon annihilation: e+e- →γγ* → γV0 and e+e- γ*γ* V$$0\atop{a}$$V$$0\atop{b}$$

We study the exclusive double-photon annihilation processes, e+e- →γγ* → γV0 and e+e- γ*γ* V$$0\atop{a}$$V$$0\atop{b}$$, where the V$$0\atop{i}$$ is a neutral vector meson produced in the forward kinematical region: s>> -t and -t >> Λ$$2\atop{QCD}$$. We show how the differential cross sections $$dσ\atop{dt}$$, as predicted by QCD, have additional falloff in the momentum transfer squared t due to the QCD compositeness of the hadrons, consistent with the leading-twist fixed-θCM scaling laws, both in terms of conventional Feynman diagrams and by using the AdS/QCD holographic model to obtain the results more transparently. However, even though they are exclusive channels and not associated with the conventional electron–positron annihilation process e+e-→γ*→ $$q\bar{q}$$, these total cross sections σ(e+e-→γV0)and σ(e+e-→V$$0\atop{a}$$V$$0\atop{b}$$), integrated over the dominant forward-and backward-θCM angular domains, scale as 1/s, and thus contribute to the leading-twist scaling behavior of the ratio Re+e-. We generalize these results to exclusive double-electroweak vector-boson annihilation processes accompanied by the forward production of hadrons, such as e+e-→Z0V0and e+e-→W-ρ+. These results can also be applied to the exclusive production of exotic hadrons such as tetraquarks, where the cross-section scaling behavior can reveal their multiquark nature.
Authors:
 [1] ;  [2] ;  [3]
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Arizona State Univ., Tempe, AZ (United States). Dept. of Physics
  3. Univ. Tuebingen (Germany). Inst. fuer Theoretische Physik, Kepler Center for Astro and Particle Physics; Tomsk State Univ. (Russian Federation); Tomsk Polytechnic Univ. (Russian Federation)
Publication Date:
OSTI Identifier:
1332769
Report Number(s):
SLAC-PUB-16809
Journal ID: ISSN 0370-2693; arXiv:1609.06635
Grant/Contract Number:
AC02-76SF00515
Type:
Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 764; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Phenomenology-HEP; HEPPH