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Atomic and molecular beams have been valuable tools for precision measurement of atomic and molecular spectra for the past several decades. In order to achieve good signal to noise in a beam spectroscopy experiment, it is important to have high fluxes, low forward velocity (to increase interaction time), and, in the case of molecules, cold internal temperatures to concentrate population in a small number of internal states. Fundamental precision measurements, such as the searches for the electron electric dipole moment and time variation of fundamental contestants, typically call for molecules containing heavy or exotic atoms with high melting points. This makes production of these molecules through the standard effusive oven source or seeded supersonic source difficult. In this paper, we further explore the buffer gas beam technique and its ability to create bright, cold, and slow beams of the refractory, chemically reactive species ThO. We find that our beam compares very favorably to state-of-the-art supersonic sources for similar species, with higher flux, lower forward velocity, comparable internal temperatures, and smaller beam divergence.