The Heavy Hybrid Spectrum from NRQCD and the Born-Oppenheimer Approximation

The Born-Oppenheimer Approximation

where R is the set of nuclear coordinates and r is the set of electronic coordinates. If spin-orbit effects are important, they can be added through a spin-orbit operator Ĥso. Unfortunately, the V̂eN(r,R) term prevents us from separating Ĥ into nuclear and electronic parts, which would allow us to write the molecular wavefunction as a product of nuclear and electronic terms, Ψ(r,R) = Ψ(r)χ(R). W...

The Heavy-Light Spectrum from Lattice NRQCD

We present a lattice investigation of heavy-light mesons in the quenched approximation, using non-relativistic QCD for the heavy quark and a clover improved Wilson formulation for the light quark. A comprehensive calculation of the heavy-light spectrum has been performed for various heavy quark masses around the b. Our results for the Bs−Bd splitting agree well with the experimental value. We f...

The Time-dependent Born-oppenheimer Approximation

We explain why the conventional argument for deriving the time-dependent Born-Oppenheimer approximation is incomplete and review recent mathematical results, which clarify the situation and at the same time provide a systematic scheme for higher order corrections. We also present a new elementary derivation of the correct second-order time-dependent Born-Oppenheimer approximation and discuss as...

How good is the born-oppenheimer approximation?

fB and the Heavy-light Spectrum from NRQCD

B physics is a subject of active research. The theoretical and experimental understanding of the B meson and b baryon spectrum is just beginning. Weak matrix elements of B mesons, e.g. fB, fBs , BB, and BBs are being studied to determine fundamental parameters of the Standard Model. This review summarizes the progress made in calculating the B spectrum and decay constants using the nonrelativis...