Exotic QQ(q)over-bar(q)over-bar, QQ(q)over-bar(s)over-bar, and QQ(s)over-bar(s)over-bar states

After constructing the possible J(P) = 0(-), 0(+), 1(-), and 1(+) QQ (q) over bar(q) over bar tetraquark interpolating currents in a systematic way, we investigate the two-point correlation functions and extract the corresponding masses with the QCD sum rule approach. We study the QQ (q) over bar(q) over bar, QQ (q) over bar(s) over bar, and QQ (s) over bar(s) over bar systems with various isospins I = 0, 1/2, 1. Our numerical analysis indicates that the masses of doubly bottomed tetraquark states are below the threshold of the two-bottom mesons, two-bottom baryons, and one doubly bottomed baryon plus one antinucleon. Very probably these doubly bottomed tetraquark states are stable. DOI: 10.1103/PhysRevD.87.014003