  We investigate the chiral structure of local vector and axial-vector
tetraquark currents, and study their chiral transformation properties. We
consider the charge-conjugation parity and classify all the isovector vector
and axial-vector local tetraquark currents of quantum numbers
I(G)J(PC)=1(-)1(-+), I(G)J(PC)=1(+)1(--), I(G)J(PC)=1(-)1(++) and
I(G)J(PC)=1(+)1(+-). We find that there is a one to one correspondence among
them. Using these currents, we perform QCD sum rule analyses. Our results
suggest that there is a missing b1 state having I(G)J(PC)=1(+)1(+-) and a mass
around 1.47-1.66 GeV.

High Energy Physics - Phenomenology