P -wave fully charm and fully bottom tetraquark states

Abstract

We have studied the mass spectra of the P-wave fully charm and fully bottom tetraquark states in the framework of quantum chromodynamics (QCD) sum rules. We construct the interpolating currents by inserting the covariant derivative operator D↔μ between the S-wave diquark and antidiquark fields. The excitation structures show that the pure λ-mode excited P-wave fully heavy tetraquarks exist for the quantum numbers JPC=1−−,1−+,2−−,2−+, and 3−−, while it is difficult to separate the λ-mode and ρ-mode excitations in the 0−+ channel. Within three Lorentz indices, there is no pure λ-mode excited P-wave fully charm/bottom tetraquark operators with JPC=0−− and 3−+. Our results support that the recent observed X(6900) and X(7200) resonances could be interpreted as the P-wave fully charm ccc¯c¯ tetraquark states with JPC=1−+ and 2−+, respectively. Some P-wave fully bottom bbb¯b¯ tetraquark states are predicted to be lower than the di-ηb(1S) and di-ϒ(1S) mass thresholds. Hopefully our calculations will be useful for identifying the nature of new exotic tetraquark states. Published by the American Physical Society 2024