Masses of the conjectured H-dibaryon at different temperatures*

Abstract

We present a lattice QCD determination of masses of the conjectured H-dibaryon, denoted as , at nine different temperatures: 0.24, 0.63, 0.76, 0.84, 0.95, 1.09, 1.27, 1.52, and 1.90. The masses of baryons N, Σ, Ξ, and Λ at different temperatures were also computed. The simulations were performed on an anisotropic lattice with flavours of clover fermion at a quark mass corresponding to . The thermal ensembles were provided by the FASTSUM collaboration, whereas the zero temperature ensembles were provided by the Hadspec collaboration. We also calculated the spectral density of the correlation function of those particles. The spectral density distributions show a rich peak structure at the lowest temperature; at intermediate temperatures, the mass values of those particles obtained by the extrapolation method reflect a two-peak structure. While the spectral density for the octet baryon becomes smooth at 1.27, 1.52, and 1.90, the spectral density for the H-dibaryon becomes smooth at . At , the mass difference of the H-dibaryon and Λ pair, expressed as , was estimated to be MeV, which suggests the existence of a bound H-dibaryon state.