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/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

The cross section for deep inelastic lepton-proton scattering (DIS) $\ell p\to \ell' X$ includes a diffractive deep inelastic (DDIS) contribution $\ell p\to \ell' p' X$, in which the proton remains intact with a large longitudinalmomentum fraction $x_F$ greater than 0.9 and small transverse momentum. TheDDIS events, which can be identified with Pomeron exchange in the $t$-channel,account for approximately $10\%$ of all of the DIS events. Thus, when onemeasures DIS, one automatically includes the leading-twist Bjorken-scaling DDISevents as a contribution to the DIS cross section, whether or not thefinal-state proton $p'$ is detected. In such events, the missing momentumfraction $x_{p'} \sim 0.9$ carried by the final-state proton $p'$ in the DDISevents could be misidentified with the light-front momentum fraction carried bysea quarks or gluons in the protons' Fock structure. As we shall show in thisarticle, the underlying QCD Pomeron-exchange amplitude which produces the DDISevents does not obey the operator product expansion nor satisfy momentum sumrules. Thus we conclude that the quark and gluon distributions measured in DISexperiments will be misidentified, unless the measurements explicitly excludethe DDIS events and that a correct determination of the parton distributionfunctions (PDFs) derived from the DIS data requires the explicit subtraction ofthe DDIS contribution from the full DIS cross section.

The Diffractive Contribution to Deep Inelastic Lepton-Proton Scattering: Implications for QCD Momentum Sum Rules and Parton Distributions