Magnetic moments of the vector hidden-charm tetraquark states

Abstract

The magnetic moment yields an excellent framework to explore the inner structure of particles determined by the quark-gluon dynamics of QCD, as it is the leading-order response of a bound system to a weak external magnetic field. Motivated by this, in this study, the magnetic moments of possible axial-vector T bcūū , T bc d d, and T bcū d tetraquarks are obtained with the help of light-cone QCD sum rules. For this purpose, we assume that these states are represented as a diquark-antidiquark picture with different structures and interpolating currents. The magnetic moment results derived using different diquark-antidiquark configurations differ substantially from each other. This can be translated into more than one tetraquark state with the same quantum number and quark content yet possessing different magnetic moments. From the numerical results obtained, we have concluded that the magnetic moments of the T bc states can project their inner structure, which can be used for their quantum numbers and quark-gluon organization. The contribution of individual quarks to the magnetic moments is also analyzed for completeness. We hope that our predictions of the magnetic moments of the T bc tetraquarks, together with the results of other theoretical investigations of the spectroscopic parameters and decay widths of these interesting tetraquarks, may be valuable in the search for these states in future experiments and in unraveling the internal structure of these tetraquarks.

Unveiling the underlying structure of axial-vector bottom-charm tetraquarks in the light of their magnetic moments

“…The use of LCSR to obtain electromagnetic properties for doubly-heavy baryons, tetraquarks and pentaquarks is illustrated in refs. [39][40][41][42][43][44][45][46][47].…”

Analysis of the $$\mathrm {X_{AV}}$$ state through its electromagnetic properties

“…For interested readers, details of this procedure performed to acquire the expression of the perturbative and non-perturbative contributions are presented in Refs. [33,45]. Using the abovementioned procedures and then applying the Fourier transform to the obtained expressions to transfer the position space expressions to the momentum space, the QCD representation of the correlation function is extracted.…”

“…Inspired by this, in the present work, the magnetic and quadrupole moments of the theoretically predicted singly-charmed state, X AV , with the quantum numbers J P = 1 + are extracted by means of the QCD light-cone sum rules method by considering the diquark-antidiquark configuration of this state with quark contents [ud][ cs]. Several studies in the literature have extracted the magnetic and quadrupole moments of hiddencharm and singly-charmed tetraquark states [24,26,[28][29][30][31][32][33][34][35][36][37].…”

Analysis of P cs (4338) and related pentaquark molecular states via QCD sum rules*

“…They show evidences that two charm quarks can correlate in a hadronic state, and has trigged high enthusiasms of different theoretic groups to study the possible doubly-charm (doubly-bottom) tetraquark states T cc (T bb ). In fact, various theoretical methods have been applied to study them, such as the colormagnetic interaction model [17,18], (simple) potential quark models [19,20,21], QCD sum rules [22,23,24,25], lattice QCD simulations [26,27,28] and so on [29,30,31].…”