2025/11/25 by Sheng Lü, Ru-Xuan Wang, Lü, Sheng +3
Physics and Astronomy · #Quantum Chromodynamics and Particle Interactions #Particle physics theoretical and experimental studies #High-Energy Particle Collisions Research
paper · pdf · doi:10.1103/47bk-jjq4
We analyze the charmless two-body decays of the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi>B</a:mi> </a:math> meson into a pseudoscalar and a vector meson, referred to as <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:mi>B</c:mi> <c:mo stretchy="false">→</c:mo> <c:mi>P</c:mi> <c:mi>V</c:mi> </c:math> decay, within the framework of the modified perturbative QCD (PQCD) approach, which was originally developed to solve the long-standing puzzles, the so-called <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"> <f:mi>π</f:mi> <f:mi>π</f:mi> </f:math> and <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"> <h:mi>π</h:mi> <h:mi>K</h:mi> </h:math> puzzles. In this method, based on the conventional PQCD calculations, soft form factors and contributions arising from color-octet quark-antiquark components in the final state are introduced, which involve essentially nonperturbative dynamics. By employing the flavor SU(3) symmetry and its breaking effect, the parameters describing soft contributions are correlated and subsequently reduced into a more concise set of SU(3) parameters. Through a <j:math xmlns:j="http://www.w3.org/1998/Math/MathML" display="inline"> <j:msup> <j:mi>χ</j:mi> <j:mn>2</j:mn> </j:msup> </j:math> analysis procedure applied to the experimental data, these parameters are determined, from which the corresponding theoretical results for the branching ratios and <l:math xmlns:l="http://www.w3.org/1998/Math/MathML" display="inline"> <l:mi>C</l:mi> <l:mi>P</l:mi> </l:math> asymmetries in <n:math xmlns:n="http://www.w3.org/1998/Math/MathML" display="inline"> <n:mi>B</n:mi> <n:mo stretchy="false">→</n:mo> <n:mi>P</n:mi> <n:mi>V</n:mi> </n:math> decays are derived. Within this framework, it is demonstrated that the theoretical calculations align well with experimental measurements, suggesting that the method developed for solving <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"> <q:mi>π</q:mi> <q:mi>π</q:mi> </q:math> and <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"> <s:mi>π</s:mi> <s:mi>K</s:mi> </s:math> puzzles can be extended to more decay modes of the <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"> <u:mi>B</u:mi> </u:math> meson. The numerical analysis shows that these soft contributions have a significant influence on the theoretical results. Furthermore, more precise experimental data are needed for deeper investigations of the <w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"> <w:mi>C</w:mi> <w:mi>P</w:mi> </w:math> asymmetries.