Identification of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msubsup> <mml:mi>D</mml:mi> <mml:mn>2</mml:mn> <mml:mo>*</mml:mo> </mml:msubsup> <mml:mo stretchy="false">(</mml:mo> <mml:mn>3000</mml:mn> <mml:mo stretchy="false">)</mml:mo> </mml:math> as the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msubsup> <mml:mi>D</mml:mi> <mml:mn>2</mml:mn> <mml:mo>*</mml:mo> </mml:msubsup> <mml:mo stretchy="false">(</mml:mo> <mml:msup> <mml:mn>2</mml:mn> <mml:mn>3</mml:mn> </mml:msup> <mml:msub> <mml:mi>P</mml:mi> <mml:mn>2</mml:mn> </mml:msub> <mml:mo stretchy="false">)</mml:mo> </mml:math> and exploring potential of undiscovered <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msup> <mml:mn>2</mml:mn> <mml:mo>+</mml:mo> </mml:msup> </mml:math> mesons via <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>B</mml:mi> </mml:math> decays

Following the discovery of the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:msubsup> <a:mi>D</a:mi> <a:mn>2</a:mn> <a:mo>*</a:mo> </a:msubsup> <a:mo stretchy="false">(</a:mo> <a:mn>3000</a:mn> <a:mo stretchy="false">)</a:mo> </a:math> , its mass and full width have been extensively studied. Yet its nature remains undetermined to date. Since it was discovered through nonleptonic decay of <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"> <e:mi>B</e:mi> </e:math> mesons and the corresponding cascade process, we therefore in this paper investigate the nonleptonic and semileptonic decays of <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:mi>B</g:mi> </g:math> meson to <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"> <i:msup> <i:mi>J</i:mi> <i:mi>P</i:mi> </i:msup> <i:mo>=</i:mo> <i:msup> <i:mn>2</i:mn> <i:mo>+</i:mo> </i:msup> </i:math> charmed mesons using the Bethe-Salpeter equation approach. Our calculations on nonleptonic <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"> <k:mi>B</k:mi> </k:math> decays reveal that the unconfirmed resonance <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"> <m:msubsup> <m:mi>D</m:mi> <m:mn>2</m:mn> <m:mo>*</m:mo> </m:msubsup> <m:mo stretchy="false">(</m:mo> <m:mn>3000</m:mn> <m:mo stretchy="false">)</m:mo> </m:math> aligns well with <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"> <q:msubsup> <q:mi>D</q:mi> <q:mn>2</q:mn> <q:mo>*</q:mo> </q:msubsup> <q:mo stretchy="false">(</q:mo> <q:msup> <q:mn>2</q:mn> <q:mn>3</q:mn> </q:msup> <q:msub> <q:mi>P</q:mi> <q:mn>2</q:mn> </q:msub> <q:mo stretchy="false">)</q:mo> </q:math> predictions. Other candidates, including <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"> <u:msubsup> <u:mi>D</u:mi> <u:mn>2</u:mn> <u:mo>*</u:mo> </u:msubsup> <u:mo stretchy="false">(</u:mo> <u:msup> <u:mn>1</u:mn> <u:mn>3</u:mn> </u:msup> <u:msub> <u:mi>F</u:mi> <u:mn>2</u:mn> </u:msub> <u:mo stretchy="false">)</u:mo> </u:math> , <y:math xmlns:y="http://www.w3.org/1998/Math/MathML" display="inline"> <y:msubsup> <y:mi>D</y:mi> <y:mn>2</y:mn> <y:mo>*</y:mo> </y:msubsup> <y:mo stretchy="false">(</y:mo> <y:msup> <y:mn>3</y:mn> <y:mn>3</y:mn> </y:msup> <y:msub> <y:mi>P</y:mi> <y:mn>2</y:mn> </y:msub> <y:mo stretchy="false">)</y:mo> </y:math> , and <cb:math xmlns:cb="http://www.w3.org/1998/Math/MathML" display="inline"> <cb:msubsup> <cb:mi>D</cb:mi> <cb:mn>2</cb:mn> <cb:mo>*</cb:mo> </cb:msubsup> <cb:mo stretchy="false">(</cb:mo> <cb:msup> <cb:mn>2</cb:mn> <cb:mn>3</cb:mn> </cb:msup> <cb:msub> <cb:mi>F</cb:mi> <cb:mn>2</cb:mn> </cb:msub> <cb:mo stretchy="false">)</cb:mo> </cb:math> , are excluded due to their very small branching ratios in <gb:math xmlns:gb="http://www.w3.org/1998/Math/MathML" display="inline"> <gb:mi>B</gb:mi> </gb:math> decays. Considering that the <ib:math xmlns:ib="http://www.w3.org/1998/Math/MathML" display="inline"> <ib:msubsup> <ib:mi>D</ib:mi> <ib:mn>2</ib:mn> <ib:mo>*</ib:mo> </ib:msubsup> <ib:mo stretchy="false">(</ib:mo> <ib:mn>1</ib:mn> <ib:mi>F</ib:mi> <ib:mo stretchy="false">)</ib:mo> </ib:math> , <mb:math xmlns:mb="http://www.w3.org/1998/Math/MathML" display="inline"> <mb:msubsup> <mb:mi>D</mb:mi> <mb:mn>2</mb:mn> <mb:mo>*</mb:mo> </mb:msubsup> <mb:mo stretchy="false">(</mb:mo> <mb:mn>3</mb:mn> <mb:mi>P</mb:mi> <mb:mo stretchy="false">)</mb:mo> </mb:math> , and <qb:math xmlns:qb="http://www.w3.org/1998/Math/MathML" display="inline"> <qb:msubsup> <qb:mi>D</qb:mi> <qb:mn>2</qb:mn> <qb:mo>*</qb:mo> </qb:msubsup> <qb:mo stretchy="false">(</qb:mo> <qb:mn>2</qb:mn> <qb:mi>F</qb:mi> <qb:mo stretchy="false">)</qb:mo> </qb:math> have not yet been experimentally observed, we investigate the feasibility of their detection in <ub:math xmlns:ub="http://www.w3.org/1998/Math/MathML" display="inline"> <ub:mi>B</ub:mi> </ub:math> -meson decays.