### Abstract

We study the exclusive double-photon annihilation processes, e^{+}e^{−}→γγ^{⁎}→γV^{0} and e^{+}e^{−}→γ^{⁎}γ^{⁎}→V_{a} ^{0}V_{b} ^{0}, where the V_{i} ^{0} is a neutral vector meson produced in the forward kinematical region: s≫−t and −t≫Λ_{QCD} ^{2}. We show how the differential cross sections dσdt, 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-θ_{CM} 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^{⁎}→qq¯, these total cross sections σ(e^{+}e^{−}→γV^{0}) and σ(e^{+}e^{−}→V_{a} ^{0}V_{b} ^{0}), integrated over the dominant forward- and backward-θ_{CM} angular domains, scale as 1/s, and thus contribute to the leading-twist scaling behavior of the ratio R_{e+e− }. We generalize these results to exclusive double-electroweak vector-boson annihilation processes accompanied by the forward production of hadrons, such as e^{+}e^{−}→Z^{0}V^{0} and 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.

Original language | English |
---|---|

Pages (from-to) | 174-179 |

Number of pages | 6 |

Journal | Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics |

Volume | 764 |

DOIs | |

Publication status | Published - 10 Jan 2017 |

### Fingerprint

### Keywords

- Electron–positron annihilation
- Electroweak bosons
- Hadron structure
- Quantum chromodynamics
- Tetraquarks
- Vector meson dominance

### ASJC Scopus subject areas

- Nuclear and High Energy Physics

### Cite this

^{+}e

^{−}→ γγ

^{⁎}→ γV

^{0}and e

^{+}e

^{−}→ γ

^{⁎}γ

^{⁎}→ V

^{0}V

^{0}.

*Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics*,

*764*, 174-179. https://doi.org/10.1016/j.physletb.2016.11.009

**QCD compositeness as revealed in exclusive vector boson reactions through double-photon annihilation : e ^{+}e^{−} → γγ^{⁎} → γV^{0} and e^{+}e^{−} → γ^{⁎}γ^{⁎} → V^{0}V^{0}.** / Brodsky, Stanley J.; Lebed, Richard F.; Lyubovitskij, Valery E.

Research output: Contribution to journal › Article

^{+}e

^{−}→ γγ

^{⁎}→ γV

^{0}and e

^{+}e

^{−}→ γ

^{⁎}γ

^{⁎}→ V

^{0}V

^{0}',

*Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics*, vol. 764, pp. 174-179. https://doi.org/10.1016/j.physletb.2016.11.009

^{+}e

^{−}→ γγ

^{⁎}→ γV

^{0}and e

^{+}e

^{−}→ γ

^{⁎}γ

^{⁎}→ V

^{0}V

^{0}. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. 2017 Jan 10;764:174-179. https://doi.org/10.1016/j.physletb.2016.11.009

}

TY - JOUR

T1 - QCD compositeness as revealed in exclusive vector boson reactions through double-photon annihilation

T2 - e+e− → γγ⁎ → γV0 and e+e− → γ⁎γ⁎ → V0V0

AU - Brodsky, Stanley J.

AU - Lebed, Richard F.

AU - Lyubovitskij, Valery E.

PY - 2017/1/10

Y1 - 2017/1/10

N2 - We study the exclusive double-photon annihilation processes, e+e−→γγ⁎→γV0 and e+e−→γ⁎γ⁎→Va 0Vb 0, where the Vi 0 is a neutral vector meson produced in the forward kinematical region: s≫−t and −t≫ΛQCD 2. We show how the differential cross sections dσdt, 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⁎→qq¯, these total cross sections σ(e+e−→γV0) and σ(e+e−→Va 0Vb 0), 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−→Z0V0 and 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.

AB - We study the exclusive double-photon annihilation processes, e+e−→γγ⁎→γV0 and e+e−→γ⁎γ⁎→Va 0Vb 0, where the Vi 0 is a neutral vector meson produced in the forward kinematical region: s≫−t and −t≫ΛQCD 2. We show how the differential cross sections dσdt, 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⁎→qq¯, these total cross sections σ(e+e−→γV0) and σ(e+e−→Va 0Vb 0), 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−→Z0V0 and 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.

KW - Electron–positron annihilation

KW - Electroweak bosons

KW - Hadron structure

KW - Quantum chromodynamics

KW - Tetraquarks

KW - Vector meson dominance

UR - http://www.scopus.com/inward/record.url?scp=84996548667&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84996548667&partnerID=8YFLogxK

U2 - 10.1016/j.physletb.2016.11.009

DO - 10.1016/j.physletb.2016.11.009

M3 - Article

AN - SCOPUS:84996548667

VL - 764

SP - 174

EP - 179

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

ER -