Regge-like spectra of excited singly heavy mesons

Abstract

In this work, we study the Regge-like spectra of excited singly heavy mesons by proposing a general Reggelike mass relations in which the slope ratio α ′ /β ′ between the radial and angular-momentum Regge trajectories is π/2 and the hadron mass undergoes a shift including the heavy quark mass and an extra binding energy between heavy quark and strange anti-quark. The relation is successfully tested against the observed spin-averaged data of the singly heavy mesons in their radially and angularly excited states. Some new predictions are made for more excited excitations and the discussion is given associated with the QCD string (flux tube) picture. I. INTRODUCTIONDuring the last two decades, heavy meson spectroscopy has been greatly enlarged due to the discovery of numerous excited charm and charm-strange states (charm mesons hereafter) by the B-Factory experiments BaBar, Belle, CLEO and recently by the LHCb experiment [1]. One of recent examples is the observations of the heavy mesons B(5970) by the CDF Collaboration in the B + π − and B 0 π + mass distributions [2] and the B J (5960) by the LHCb Collaboration in the Bπ mass distributions [3]. The first observation determined the mass of the B (5970) resonances to be 5978 ± 5 ± 12 MeV for the neutral state and to be 5961 ± 5 ± 12 MeV for the charged state. The second observation, giving the mass of 5969.2 ± 2.9 ± 5.3 MeV for the neutral state and 82.3 ± 7.7 ± 9 : 4 MeV for the charged state for B J (5960), seems to be consistent with the B(5970) in their properties, and they may be the same state. Another example is the observation of the charmed states of D J (3000) by the LHCb Collaboration in the Dπ mass distribution data from pp collision [4,5]. These experimental findings arouses theoretical interests to explore and accommodate the newly-discovered states with various approaches, e.g., with the potential quark models [6-18], Lattice QCD [19,20] and other approaches (see Ref.[21] for a recent review). For the B(5970), the two main interpretations exist, with the assignments 2 3 S 1 [22] and the candidate of 1 3 D 3 state [23]. For the D J (3000) and D * J (3000), there are the different interpretations, the D(3 1 S 0 ) and the D(3 3 S 1 ) states, respectively, or the candidates of D(1F) or D(2P). For the D * 2 (3000) the prediction favoring D(3 3 P 2 ) was given [24].In Ref. [25], a comprehensive analysis was made for the whole singly heavy systems of mesons and baryons using the Regge-like mass relation,with M Q the heavy quark mass, supporting that all heavy-light hadrons fall on straight lines in a "shifted" orbital trajectory plane: M → M − M Q , with the slope (α) nearly half of that for the light hadrons. Here, L is the orbital angular momentum of the hadron system. This reflects that the notion of Regge trajectory, which is widely-used in light-flavor sector and stems * Electronic address: jiadj@nwnu.edu.cn from the well-known Regge theory of the scattering matrix [26], remains to be useful in the spectra of the heavy flavor hadrons if one shifts the h...

Excited mesons, baryons, glueballs and tetraquarks: predictions of the Holography Inspired Stringy Hadron model

“…The Regge trajectories are a central feature of the hadron spectrum, and are still widely used today to characterize the spectrum of hadrons [68][69][70][71][72][73][74][75][76][77], although these descriptions usually deal only with light hadrons. Not only do we have the linear or near-linear trajectories of the light hadrons such as the ρ meson or the nucleons, but the picture also extends to the HISH mass modified Regge trajectories of hadrons including heavy quarks.…”

Bottomonium spectrum in the relativistic flux tube model

“…[53,71]. The RFT model has been applied to study the masses of heavy-light mesons [72][73][74], charmonium states [75], single heavy baryons [54,76], glueballs [77,78], and other exotic hadrons [79].…”

Bottom-charmed meson spectrum from a QCD approach based on the Tamm-Dancoff approximation

“…This is in qualitative accordance with other works that have investigated heavy quarkonia states; see, for instance, Refs. [51][52][53][54][55]. Notwithstanding, using the linear approximation for the Regge trajectories through the laws [52,[56][57][58], Ref.…”