2026/03/19 by Anonymous, Andrew D. Hanlon, Daniel Darvish +8
Physics and Astronomy · #Quantum Chromodynamics and Particle Interactions #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism
paper · pdf · doi:10.1103/bs45-shv9
The role of tetraquark operators in studying the isodoublet strange <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi>κ</a:mi> </a:math> and isovector nonstrange <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:msub> <c:mi>a</c:mi> <c:mn>0</c:mn> </c:msub> <c:mo stretchy="false">(</c:mo> <c:mn>980</c:mn> <c:mo stretchy="false">)</c:mo> </c:math> scalar mesons in lattice quantum chromodynamics (QCD) is examined using an ensemble with <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:msub> <g:mi>m</g:mi> <g:mi>π</g:mi> </g:msub> <g:mo>≈</g:mo> <g:mn>230</g:mn> <g:mtext> </g:mtext> <g:mtext> </g:mtext> <g:mi>MeV</g:mi> </g:math> and spatial extent <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"> <i:mi>L</i:mi> </i:math> such that <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"> <k:msub> <k:mi>m</k:mi> <k:mi>π</k:mi> </k:msub> <k:mi>L</k:mi> <k:mo>≈</k:mo> <k:mn>4.4</k:mn> </k:math> . Hermitian correlation matrices using both single-meson, meson-meson, and tetraquark interpolating operators are used to extract the spectrum of finite-volume stationary states in the appropriate symmetry channels. Hundreds of local and extended tetraquark operators are explored. Determinations of the spectrum in each channel are found to be unreliable without the inclusion of at least one tetraquark operator. For example, the inclusion of tetraquark operators with isospin <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"> <m:mrow> <m:mn>1</m:mn> <m:mo>/</m:mo> <m:mn>2</m:mn> </m:mrow> </m:math> and strangeness 1 quantum numbers reveals the existence of an additional energy level in the <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"> <o:mi>K</o:mi> <o:mi>η</o:mi> </o:math> subsystem below the <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"> <q:mi>K</q:mi> <q:mi>η</q:mi> </q:math> threshold. The implications of this on parametrizing the scattering <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"> <s:mi>K</s:mi> </s:math> -matrix through a well-known quantization condition to extract properties of the <u:math xmlns:u="http://www.w3.org/1998/Math/MathML" display="inline"> <u:mi>κ</u:mi> </u:math> and <w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"> <w:msub> <w:mi>a</w:mi> <w:mn>0</w:mn> </w:msub> <w:mo stretchy="false">(</w:mo> <w:mn>980</w:mn> <w:mo stretchy="false">)</w:mo> </w:math> scalar meson resonances are discussed.