The b1Sigma+(b0(+)) left and right arrow X3Sigma-(X10(+),X21) transitions of SbH and SbD have been studied by laser-induced fluorescence measurements. Ground state SbH(SbD) radicals were generated in a fast-flow system by reaction of microwave-discharged hydrogen (deuterium) with antimony vapor. Vibrational levels v = 0 and 1 of the b1Sigma+ state were excited with a pulsed dye laser. In addition to five electric dipole branches SR, QP, QR, QQ, and OP, weak magnetic dipole branches PQ were observed in the 0-0 bands of the b1Sigma+ <-- X3Sigma- transitions. Rotational and vibrational constants of the X3Sigma- and b1Sigma+ states were deduced from high-resolution excitation spectra. Time-resolved measurements of the fluorescence decay and measurements of relative line and band intensities allowed determination of the radiative lifetime of the b1Sigma+ state of SbH (tau = 173 +/- 3 µs) and of the electric and magnetic dipole transition moments µ0 = +/-0.036 D, µ1 = -/+0.058 D, |M| = 1.62 Bohr magnetons. Copyright 1998 Academic Press.