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Title: Enhanced molecular yield from a cryogenic buffer gas beam source via excited state chemistry
Abstract

We use narrow-band laser excitation of Yb atoms to substantially enhance the brightness of a cold beam of YbOH, a polyatomic molecule with high sensitivity to physics beyond the standard model (BSM). By exciting atomic Yb to the metastable3P1state in a cryogenic environment, we significantly increase the chemical reaction cross-section for collisions of Yb with reactants. We characterize the dependence of the enhancement on the properties of the laser light, and study the final state distribution of the YbOH products. The resulting bright, cold YbOH beam can be used to increase the statistical sensitivity in searches for new physics utilizing YbOH, such as electron electric dipole moment and nuclear magnetic quadrupole moment experiments. We also perform new quantum chemical calculations that confirm the enhanced reactivity observed in our experiment and compare reaction pathways of Yb(3P) with the reactants H2O and H2O2. More generally, our work presents a broad approach for improving experiments that use cryogenic molecular beams for laser cooling and precision measurement searches of BSM physics.

Authors:
; ; ; ;
Award ID(s):
1908634
Publication Date:
NSF-PAR ID:
10302740
Journal Name:
New Journal of Physics
Volume:
22
Issue:
2
Page Range or eLocation-ID:
Article No. 022002
ISSN:
1367-2630
Publisher:
IOP Publishing
Sponsoring Org:
National Science Foundation
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