We realize a continuous guided beam of cold deuterated ammonia with flux of 3 × 10 11 ND 3 molecules s −1 and a continuous free-space beam of cold potassium with flux of 1 × 10 16 K atoms s −1 . A novel feature of the buffer gas source used to produce these beams is cold neon, which, due to intermediate Knudsen number beam dynamics, produces a forward velocity and low-energy tail that is comparable to much colder helium-based sources. We expect this source to be trivially generalizable to a very wide range of atomic and molecular species with significant vapor pressure below 1000 K. This source has properties that make it a good starting point for laser cooling of molecules or atoms, cold collision studies, trapping, or nonlinear optics in buffer-gas-cooled atomic or molecular gases.

Employing a two-stage cryogenic buffer gas cell, we produce a cold, hydrodynamically extracted beam of calcium monohydride molecules with a near effusive velocity distribution. Beam dynamics, thermalization and slowing are studied using laser spectroscopy. The key to this hybrid, effusive-like beam source is a "slowing cell" placed immediately after a hydrodynamic, cryogenic source [Patterson et al., J. Chem. Phys., 2007, 126, 154307]. The resulting CaH beams are created in two regimes. One modestly boosted beam has a forward velocity of v f = 65 m/s, a narrow velocity spread, and a flux of 10 9 molecules per pulse. The other has the slowest forward velocity of v f = 40 m/s, a longitudinal temperature of 3.6 K, and a flux of 5 × 10 8 molecules per pulse.

No abstract

No abstract