nonperturbative
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Prof. Jia Yu from the Institute of High Energy Physics of the Chinese Academy of Sciences, and his teammates, unveiled unexpectedly some profound associations between two essential nonperturbative boundaries that describe the intrinsic properties of heavy mesons—supportive for foreseeing substantial meson hard exclusive production processes with better precision. The investigation was published in Physical Review Letters, following up on an examination distributed in Physical Review D in 2019.

Quantum chromodynamics (QCD) is the major hypothesis to portray the strong association in nature, & heavy meson refers to a hadron made out of a heavy quark and a light antiquark limited by the solid force.

The research of the heavy hadron production mechanism is a significant subject in the field of perturbative QCD. From one viewpoint, the heavy meson light-cone dissemination abundancy (LCDA) characterized in substantial quark successful hypothesis (HQET) is the fundamental nonperturbative information boundary, which universally shows up in foreseeing B-meson elite rots, and assumes a crucial function in weighty flavor material science. Then again, the collinear factorization hypothesis neglected to handle B-meson select creation and rather uses the weighty meson LCDA characterized in QCD, which is ineffectively obliged at present.

Over the past three decades, it was commonly believed that these two sets of nonperturbative B-meson LCDAs were independent of each other.

Due to asymptotic freedom in QCD, physicists have realized that, although these two nonperturbative functions have drastically different ultraviolet behavior, they possess identical infrared behavior.

Then they proposed a novel factorization theorem to link these two sets of functions together: The QCD LCDA of B-meson can be expressed as a convolution between the HQET LCDA of B-meson and a perturbatively calculable short-distance coefficient.

This factorization program not only helps to cleanly separate the  affiliated with three important energy scales intrinsic to hard exclusive B production processes but expedites the resummation of large logarithms. The novel theorem also employs the HQET LCDA of B-meson as the input parameter, which has already been extensively studied in innumerable B-meson decay channels, so that one can greatly improve the accuracy of theoretical predictions.