Next-to-leading-order QCD calculations of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>B</mml:mi> <mml:mo stretchy="false">→</mml:mo> <mml:mi>A</mml:mi> </mml:math> form factors with higher-twist corrections

Applying the light-cone sum rules approach, the next-to-leading-order corrections to <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi>B</a:mi> <a:mo stretchy="false">→</a:mo> <a:mi>A</a:mi> </a:math> form factors are calculated with the twist-two and twist-three <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"> <d:mi>B</d:mi> </d:math> -meson light-cone distribution amplitudes (LCDAs) at leading power in <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"> <f:mi mathvariant="normal">Λ</f:mi> <f:mo>/</f:mo> <f:msub> <f:mi>m</f:mi> <f:mi>b</f:mi> </f:msub> </f:math> . At one-loop level, the vacuum-to- <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"> <i:mi>B</i:mi> </i:math> -meson correlation functions defined with interpolating currents for the <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"> <k:mi>p</k:mi> </k:math> -wave axial-vector meson are factorized into short-distance coefficients and the distribution amplitudes of the <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"> <m:mi>B</m:mi> </m:math> meson, among which the hard coefficients for A0-type currents and <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"> <o:mi>μ</o:mi> </o:math> -dependent jet functions entering correlation functions <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"> <q:msubsup> <q:mi mathvariant="normal">Π</q:mi> <q:mrow> <q:mi>μ</q:mi> <q:mo>,</q:mo> <q:mo stretchy="false">∥</q:mo> </q:mrow> <q:mrow> <q:mo stretchy="false">(</q:mo> <q:mi>T</q:mi> <q:mo>+</q:mo> <q:mover accent="true"> <q:mi>T</q:mi> <q:mo stretchy="false">˜</q:mo> </q:mover> <q:mo stretchy="false">)</q:mo> </q:mrow> </q:msubsup> </q:math> , <y:math xmlns:y="http://www.w3.org/1998/Math/MathML" display="inline"> <y:msubsup> <y:mi mathvariant="normal">Π</y:mi> <y:mrow> <y:mi>δ</y:mi> <y:mi>μ</y:mi> <y:mo>,</y:mo> <y:mo>⊥</y:mo> </y:mrow> <y:mrow> <y:mo stretchy="false">(</y:mo> <y:mi>V</y:mi> <y:mo>−</y:mo> <y:mi>A</y:mi> <y:mo stretchy="false">)</y:mo> </y:mrow> </y:msubsup> </y:math> , and <db:math xmlns:db="http://www.w3.org/1998/Math/MathML" display="inline"> <db:msubsup> <db:mi mathvariant="normal">Π</db:mi> <db:mrow> <db:mi>δ</db:mi> <db:mi>μ</db:mi> <db:mo>,</db:mo> <db:mo>⊥</db:mo> </db:mrow> <db:mrow> <db:mo stretchy="false">(</db:mo> <db:mi>T</db:mi> <db:mo>+</db:mo> <db:mover accent="true"> <db:mi>T</db:mi> <db:mo stretchy="false">˜</db:mo> </db:mover> <db:mo stretchy="false">)</db:mo> </db:mrow> </db:msubsup> </db:math> are identical to the corresponding ones of <kb:math xmlns:kb="http://www.w3.org/1998/Math/MathML" display="inline"> <kb:mi>B</kb:mi> <kb:mo stretchy="false">→</kb:mo> <kb:mi>V</kb:mi> </kb:math> in soft-collinear effective theory (SCET). In addition, <nb:math xmlns:nb="http://www.w3.org/1998/Math/MathML" display="inline"> <nb:msubsup> <nb:mi mathvariant="normal">Π</nb:mi> <nb:mrow> <nb:mi>μ</nb:mi> <nb:mo>,</nb:mo> <nb:mo stretchy="false">∥</nb:mo> </nb:mrow> <nb:mrow> <nb:mo stretchy="false">(</nb:mo> <nb:mi>V</nb:mi> <nb:mo>−</nb:mo> <nb:mi>A</nb:mi> <nb:mo stretchy="false">)</nb:mo> </nb:mrow> </nb:msubsup> </nb:math> and <tb:math xmlns:tb="http://www.w3.org/1998/Math/MathML" display="inline"> <tb:msubsup> <tb:mi mathvariant="normal">Π</tb:mi> <tb:mrow> <tb:mi>μ</tb:mi> <tb:mo>,</tb:mo> <tb:mo stretchy="false">∥</tb:mo> </tb:mrow> <tb:mrow> <tb:mo stretchy="false">(</tb:mo> <tb:mi>T</tb:mi> <tb:mo>+</tb:mo> <tb:mover accent="true"> <tb:mi>T</tb:mi> <tb:mo stretchy="false">˜</tb:mo> </tb:mover> <tb:mo stretchy="false">)</tb:mo> </tb:mrow> </tb:msubsup> </tb:math> coincide with the results of <bc:math xmlns:bc="http://www.w3.org/1998/Math/MathML" display="inline"> <bc:mi>B</bc:mi> <bc:mo stretchy="false">→</bc:mo> <bc:mi>π</bc:mi> <bc:mo>,</bc:mo> <bc:mi>K</bc:mi> </bc:math> under the limit <ec:math xmlns:ec="http://www.w3.org/1998/Math/MathML" display="inline"> <ec:msub> <ec:mi>m</ec:mi> <ec:mi>q</ec:mi> </ec:msub> <ec:mo stretchy="false">→</ec:mo> <ec:mn>0</ec:mn> </ec:math> up to one-loop accuracy. Then the subleading-power corrections to <hc:math xmlns:hc="http://www.w3.org/1998/Math/MathML" display="inline"> <hc:mi>B</hc:mi> <hc:mo stretchy="false">→</hc:mo> <hc:mi>A</hc:mi> </hc:math> form factors are computed with the higher-twist <kc:math xmlns:kc="http://www.w3.org/1998/Math/MathML" display="inline"> <kc:mi>B</kc:mi> </kc:math> -meson LCDAs at tree level up to the twist-six accuracy. Furthermore, we predict the <mc:math xmlns:mc="http://www.w3.org/1998/Math/MathML" display="inline"> <mc:msup> <mc:mi>q</mc:mi> <mc:mn>2</mc:mn> </mc:msup> </mc:math> dependence of <oc:math xmlns:oc="http://www.w3.org/1998/Math/MathML" display="inline"> <oc:mi>B</oc:mi> <oc:mo stretchy="false">→</oc:mo> <oc:mi>A</oc:mi> </oc:math> form factors via the Bourrely-Caprini-Lellouch <rc:math xmlns:rc="http://www.w3.org/1998/Math/MathML" display="inline"> <rc:mi>z</rc:mi> </rc:math> -series expanding parametrization to compute several physical observables including branching ratios of semileptonic <tc:math xmlns:tc="http://www.w3.org/1998/Math/MathML" display="inline"> <tc:mi>B</tc:mi> <tc:mo stretchy="false">→</tc:mo> <tc:mi>A</tc:mi> <tc:mo>ℓ</tc:mo> <tc:msub> <tc:mover accent="true"> <tc:mi>ν</tc:mi> <tc:mo stretchy="false">¯</tc:mo> </tc:mover> <tc:mo>ℓ</tc:mo> </tc:msub> </tc:math>