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 Plus

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

Zendy Tools

Zendy Open

We compare the extraction of the ground-state decay constant from thetwo-point correlator in QCD and in potential models and show that the resultsobtained at each step of the extraction procedure follow a very similarpattern. We prove that allowing for a Borel-parameter-dependent effectivecontinuum threshold yields two essential improvements compared to employing aBorel-parameter-independent quantity: (i) It reduces considerably the(unphysical) dependence of the extracted bound-state mass and the decayconstant on the Borel parameter. (ii) In a potential model, where the actualvalue of the decay constant is known from the Schroedinger equation, aBorel-parameter-dependent threshold leads to an improvement of the accuracy ofthe extraction procedure. Our findings suggest that in QCD a Borel-parameterdependent threshold leads to a more reliable and accurate determination ofbound-state characteristics by the method of sum rules.

Extraction of ground-state decay constant from dispersive sum rules: QCD vs potential models