Masses of doubly heavy tetraquarks QQq̄n̄ with JP = 1+

Abstract

In this paper, we apply the method of QCD sum rules to study the doubly heavy tetraquark states [Formula: see text] with spin-parity [Formula: see text] and strangeness [Formula: see text] using careful estimates of the Borel and threshold parameters involved. Masses of the doubly bottom and charmed tetraquarks with isospin [Formula: see text] are computed precisely via taking into account multifarious condensates up to dimension 10. Compared with the two-heavy meson thresholds, we find that all nonstrange doubly-bottom tetraquarks and a doubly-charmed tetraquarks associated with [Formula: see text] with [Formula: see text] are stable against strong decay into two bottom mesons while a doubly-charmed tetraquark associated with current [Formula: see text] is unstable against strong decay. By the way, weak decay widths of the doubly bottom tetraquarks are also given.