Isospin eigenstates of the color singlet-singlet type pentaquark states

Abstract

In this article, we construct the color-singlet-color-singlet type five-quark currents with the isospins (I, I3) = ( 12 , 1 2 ) and ( 32 , 1 2 ) unambiguously to explore the DΣc, DΣ * c , D * Σc and D * Σ * c molecular states via the QCD sum rules for the first time. The numerical results support assigning the Pc(4312), Pc(4380), Pc(4440) and Pc(4457) as the DΣc, DΣ * c , D * Σc and D * Σ * c pentaquark molecular states with the isospin I = 1 2 , respectively. The corresponding DΣc, DΣ * c , D * Σc and D * Σ * c pentaquark molecular states with the isospin I = 32 have slightly larger masses, the observations of the higher pentaquark molecule candidates in the J/ψ∆ invariant mass spectrum would shed light on the nature of the Pc states, and make contributions in distinguishing the scenarios of pentaquark states and pentaquark molecular states.

Study of isospin eigenstates of the pentaquark molecular states with strangeness

“…It has achieved many successful descriptions, such as the tetraquark states [27,28,29,30,31], tetraquark molecular states [32,33], pentaquark states [34,35], pentaquark molecular states [23,36,37,38,39,40], dibaryon and baryonium [41,42,43,44,45] and so on. However, the isospins of the states are seldom differentiated except our previous calculation [24], it shows that mass of the high isospin state is a few dozens of MeV above that of the low one. As is known, deviation of a few dozens of MeV is enough to confuse the assignment of the state, thus, we argue that the differentiation of the isospin may be one of the key preconditions for the accurate assignment.…”

“…4, and the numerical results extracted from the Borel platforms are displayed in the Table 1, in this table, one can clearly find the thresholds of the open meson and baryon pairs. The present study belongs to the systematic research of the color singlet-singlet-type pentaquark states under the eigenstates of isospins, the results of P c states from our previous study [24] are also attached in the Table 1 for the sake of our whole physical perspectives of the S-wave meson-baryon molecule under the eigenstates of isospins for the pentaquark states with and without strangeness. The dimensional contribution of the Borel platforms' centers are shown in the Fig.…”

“…The numerical results and conclusion of this paper may present a reference for the experimental search of the other pentaquark states with strangeness except P cs (4459), they may be confronted to the future experimental observation via the search of J/ψΛ invariant mass spectrum, if the future experimental search for the other pentaquark states with strangeness predicted in the present work except P cs (4459) hold, this will in return solidify the assignment of P cs (4459) and shed light on the low-energy QCD dynamics. 1: Numerical results extracted from the Borel windows and assignments of the pentaquark states with strangeness for high and low isospins, numerical results and assignments of pentaquark states without strangeness for high and low isospins are also attached [24], thresholds of the meson-baryon pairs are listed.…”

“…In Ref. [24], the isospins are unambiguously distinguished to study the hadron-hadron molecules in the framework of QCD sum rules for the first time and the P c (4312), P c (4380), P c (4440) and P c (4457) are assigned as the D( * ) Σ ( * ) c molecules with low isospin I = 1 2 in detail, intrigued by our previous works, we are very interested to investigate the present topic: what about the situation if we differentiate the isospins for the pentaquark states with strangeness? Can we clearly determine the nature of P cs (4459)?…”

Hidden-charm pentaquark states through current algebra: from their production to decay *

“…We use the current as an example, whose spectral density can be found in Eq. (A1), and apply the following QCD sum rule parameter values [93][94][95][96][97][98][99][100][101]:…”