Untitled

Pire, B.; Semenov-Tian-Shansky, K.; Szymanowski, L.

doi:10.1007/978-3-319-65732-5_38

Cited by 5 publications

(7 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To calculate a scattering amplitude in this framework, the TDAs are to be convoluted with a hard amplitude A H calculated in perturbative QCD. this hard amplitude has the same scaling behaviour in Q 2 as the nucleon form factor (A H ∼ Q −4 ), leading for instance to σ T ∝ Q −8 in electroproduction cross sections (see section 7.1 of [12]).…”

Section: Collinear Qcd Factorization and Baryon-to-meson Tdasmentioning

confidence: 88%

See 1 more Smart Citation

Progress and Opportunities in Backward angle (u-channel) Physics

Gayoso,

Bibrzycki,

Diehl

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the uchannel, as discussed in the first Backward angle (uchannel) Physics Workshop. In particular, we discuss backward angle measurements and their theoretical description via both hadronic models and the collinear factorization approach, and discuss planned future measurements of u-channel physics. Finally, we propose outstanding questions and challenges for u-channel physics.

show abstract

Section: Collinear Qcd Factorization and Baryon-to-meson Tdasmentioning

confidence: 88%

“…The baryon-to-meson TDAs (see [12] for a review) are defined within the QCD collinear factorisation scheme through matrix elements of the non-local three-quark (antiquark) operators on the light cone (n 2 = 0):…”

Section: Collinear Qcd Factorization and Baryon-to-meson Tdasmentioning

confidence: 99%

Progress and Opportunities in Backward angle (u-channel) Physics

Gayoso,

Bibrzycki,

Diehl

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Experimentally, one may access TDAs both in the space-like domain with backward electroproduction of mesons at JLab and COMPASS and in the time-like domain in antiproton nucleon annihilation at PANDA. We also expect [30] the time-reversed π → N TDAs to be accessible at J-Parc through the reactions: π − p → J/ψ n ; π − p → γ * n → µ + µ − n. Extracting TDAs from space-like and time-like reactions will be a stringent test of their universality [31], and hence of the factorization property of hard exclusive amplitudes. This hopefully will help us to disentangle details of the complex dynamics of quark and gluon confinement in hadrons.…”

Section: Discussionmentioning

confidence: 99%

Baryon-to-Meson Transition Distribution Amplitudes: Formalism and Models

2017

Self Cite

View full text Add to dashboard Cite

In specific kinematics, hard exclusive amplitudes may be factorized into a short distance dominated part computable in a perturbative way on the one hand, and universal, confinement related hadronic matrix elements on the other hand. The extension of this description to processes such as backward meson electroproduction and forward meson production in antiproton-nucleon scattering leads to define new hadronic matrix elements of three quark operators on the light cone, the nucleon-to-meson transition distribution amplitudes, which shed a new light on the nucleon structure.

show abstract

“…The TDA collinear factorization has made two specific qualitative predictions regarding backward meson electroproduction, which can be verified experimentally [25,37,41,50]:…”

Section: Two Predictions From Tda Collinear Factorizationmentioning

confidence: 94%

Backward-angle Exclusive pi0 Production above the Resonance Region

Li¹,

Huber²,

Stevens³

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

The proposed measurement is a dedicated study of the exclusive electroproduction process, 1 H(e, e ′ p)π 0 , in the backward-angle regime (u-channel process) above the resonance region. Here, the produced π 0 is emitted 180 degrees opposite to the virtual-photon momentum (at large momentum transfer). This study also aims to apply the well-known Rosenbluth separation technique that provides the model-independent (L/T) differential cross-section at the never explored u-channel kinematics region (−t = −t max , −u = −u min ).Currently, the "soft-hard transition" in u-channel meson production remains an interesting and unexplored subject. The available theoretical frameworks offer competing interpretations for the observed backward-angle cross section peaks. In a "soft" hadronic Regge exchange description, the backward meson production comes from the interference between nucleon exchange and the meson produced via re-scattering within the nucleon. Whereas in the "hard" GPD-like backward collinear factorization regime, the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes (TDAs), otherwise known as super skewed parton distributions (SuperSPDs). Both TDAs and SPDs are universal non-perturbative objects of nucleon structure accessible only through backward-angle kinematics.The separated cross sections: σ T , σ L and (σ T /σ L ) ratio at Q 2 =2-6 GeV 2 , provide a direct test of two predictions from the TDA model: σ T ∝ 1/Q 8 and the σ T ≫ σ L in u-channel kinematics. The magnitude and u-dependence of the separated cross sections also provide a direct connection to the re-scattering Regge picture. The extracted interaction radius (from u-dependence) at different Q 2 can be used to study the soft-hard transition in the u-channel kinematics. The acquisition of these data will be an important step forward in validating the existence of a backward factorization scheme (TDA and SuperSPD) of the nucleon structure function and establishing its applicable kinematic range.

show abstract

Untitled

Cited by 5 publications

References 30 publications

Progress and Opportunities in Backward angle (u-channel) Physics

Progress and Opportunities in Backward angle (u-channel) Physics

Baryon-to-Meson Transition Distribution Amplitudes: Formalism and Models

Backward-angle Exclusive pi0 Production above the Resonance Region

Contact Info

Product

Resources

About