Molecular charmed baryons and pentaquarks from light-meson exchange saturation
Mao-Jun Yan, Fang‐Zheng Peng, Manuel Pavón Valderrama
Abstract
The spectrum of the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>c</a:mi><a:mi>q</a:mi><a:mi>q</a:mi></a:math> baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msub><c:mi mathvariant="normal">Σ</c:mi><c:mi>c</c:mi></c:msub><c:mo stretchy="false">(</c:mo><c:mn>2800</c:mn><c:mo stretchy="false">)</c:mo></c:math> or the <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:msub><h:mi mathvariant="normal">Λ</h:mi><h:mi>c</h:mi></h:msub><h:mo stretchy="false">(</h:mo><h:mn>2940</h:mn><h:mo stretchy="false">)</h:mo></h:math>. Here we explore the spectrum of two-body systems composed of a light, octet baryon and a charmed meson (or antimeson) within a simple contact-range theory in which the couplings are saturated by light-meson exchanges. This results in the prediction of a series of composite anticharmed pentaquarks (<m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mrow><m:mover accent="true"><m:mrow><m:mi>c</m:mi></m:mrow><m:mrow><m:mo stretchy="false">¯</m:mo></m:mrow></m:mover><m:mi>q</m:mi><m:mi>q</m:mi><m:mi>q</m:mi><m:mi>q</m:mi></m:mrow></m:math>) and singly charmed baryons (<q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:mi>c</q:mi><q:mover accent="true"><q:mi>q</q:mi><q:mo stretchy="false">¯</q:mo></q:mover><q:mi>q</q:mi><q:mi>q</q:mi><q:mi>q</q:mi></q:math>). Among the latter we find <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"><u:mi>J</u:mi><u:mo>=</u:mo><u:mfrac><u:mn>1</u:mn><u:mn>2</u:mn></u:mfrac></u:math> <w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"><w:mi mathvariant="normal">Ξ</w:mi><w:mi>D</w:mi></w:math> and <z:math xmlns:z="http://www.w3.org/1998/Math/MathML" display="inline"><z:mi>J</z:mi><z:mo>=</z:mo><z:mfrac><z:mn>3</z:mn><z:mn>2</z:mn></z:mfrac></z:math> <bb:math xmlns:bb="http://www.w3.org/1998/Math/MathML" display="inline"><bb:mi mathvariant="normal">Ξ</bb:mi><bb:msup><bb:mi>D</bb:mi><bb:mo>*</bb:mo></bb:msup></bb:math> bound states with masses matching those of the recently observed <eb:math xmlns:eb="http://www.w3.org/1998/Math/MathML" display="inline"><eb:msub><eb:mi mathvariant="normal">Ω</eb:mi><eb:mi>c</eb:mi></eb:msub><eb:mo stretchy="false">(</eb:mo><eb:mn>3185</eb:mn><eb:mo stretchy="false">)</eb:mo></eb:math> and <jb:math xmlns:jb="http://www.w3.org/1998/Math/MathML" display="inline"><jb:msub><jb:mi mathvariant="normal">Ω</jb:mi><jb:mi>c</jb:mi></jb:msub><jb:mo stretchy="false">(</jb:mo><jb:mn>3327</jb:mn><jb:mo stretchy="false">)</jb:mo></jb:math> baryons. Published by the American Physical Society 2024