English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We show that exclusive production of a pair of high transverse momentumphotons in pion-nucleon collisions can be systematically studied in QCDfactorization approach if the photon's transverse momentum $q_T$ with respectto the colliding pion is much greater than $\Lambda_{\rm QCD}$. We demonstratethat the leading power non-perturbative contributions to the scatteringamplitudes of this exclusive process are process-independent and can besystematically factorized into universal pion's distribution amplitudes (DAs)and nucleon's generalized parton distributions (GPDs), which are convolutedwith corresponding infrared safe and perturbatively calculable short-distancehard parts. The correction to this factorized expression is suppressed bypowers of $1/q_T$. We demonstrate quantitatively that this new type ofexclusive processes is not only complementary to existing processes forextracting GPDs, but also capable of providing an enhanced sensitivity to thedependence of both DAs and GPDs on the active parton's momentum fraction $x$.We also introduce additional, but the same type of exclusive observables toenhance our capability to explore GPDs, in particular, their $x$-dependence.

Exclusive production of a pair of high transverse momentum photons in pion-nucleon collisions for extracting generalized parton distributions