The heavy hybrid spectrum from NRQCD and the Born-Oppenheimer approximation

The spectrum of heavy-quark hybrids is studied in the leading Born-Oppenhei mer (LBO) approximation and using leading-order NRQCD simulations with an i mproved gluon action on anisotropic lattices. The masses of four hybrid sta tes are obtained from our simulations for lattice spacings 0.1 fm and 0.2 f m and are compared to the LBO predictions obtained using previously-determi ned glue-excited static potentials. The consistency of results from the two approaches reveals a compelling physical picture for heavy-quark hybrid st ates.