Quark

Spin (aerodynamics)

Ground state

Meson

Nuclear physics

Particle physics

Invariant mass

Atomic physics

Hadron

Economics

Thermodynamics

Physics

Mathematics

Homogeneous space

X(3872)

Geometry

Quark model

Quarkonium

Finance

Order (exchange)

Physical review. D/Physical review. D.

Recently, the LHCb Collaboration reported a near-threshold enhancement $X(3960)$ in the ${D}_{s}^{+}{D}_{s}^{\ensuremath{-}}$ invariant mass distribution. We show that the data can be well described by either a bound or a virtual state below the ${D}_{s}^{+}{D}_{s}^{\ensuremath{-}}$ threshold. The mass given by the pole position is ($3928\ifmmode\pm\else\textpm\fi{}3$) MeV. Using this mass and the existing information on the $X(3872)$ and ${Z}_{c}(3900)$ resonances, a complete spectrum of the $S$-wave hadronic molecules formed by a pair of ground state charmed and anticharmed mesons is established. Thus, pole positions of the partners of the $X(3872)$, ${Z}_{c}(3900)$, and the newly observed ${D}_{s}^{+}{D}_{s}^{\ensuremath{-}}$ state are predicted. Calculations have been carried out at the leading order of nonrelativistic effective field theory and considering both heavy quark spin and light flavor SU(3) symmetries, though conservative errors from the breaking of these symmetries are provided.

Establishing the heavy quark spin and light flavor molecular multiplets of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>X</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>3872</mml:mn><mml:mo stretchy="false">)</mml:mo></mml:math> , <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>Z</mml:mi><mml:mi>c</mml:mi></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:mn>3900</mml:mn><mml:mo stretchy="false">)</mml:mo…

Establishing the heavy quark spin and light flavor molecular multiplets of the X(3872) , Zc(3900)