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A supersonic beam of cold lithium hydride molecules

S. K. Tokunaga·J. O. Stack·J. J. Hudson·B. E. Sauer·E. A. Hinds·M. R. Tarbutt
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Abstract

We have developed a source of cold LiH molecules for Stark deceleration and trapping experiments. Lithium metal is ablated from a solid target into a supersonically expanding carrier gas. The translational, rotational and vibrational temperatures are 0.9(0.1) K, 5.9(0.5) K and 468(17) K respectively. Although they have not reached thermal equilibrium with the carrier gas, we estimate that 90% of the LiH molecules are in the ground state, X^{1} Σ^{+} (v=0, J=0). With a single 7 ns ablation pulse, the number of molecules in the ground state is 4.5(1.8)*10^{7} molecules per steradian. A second, delayed, ablation pulse produces another LiH beam in a different part of the same gas pulse, thereby almost doubling the signal. A long pulse, lasting 150 microseconds, can make the beam up to 15 times more intense.

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S. K. Tokunaga, J. O. Stack, J. J. Hudson, B. E. Sauer, E. A. Hinds, M. R. Tarbutt. 2006-12-16. A supersonic beam of cold lithium hydride molecules. https://doi.org/10.1063/1.2711434

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