AUTHOR=Hendricks R. J. , Holland D. A. , Truppe S. , Sauer B. E. , Tarbutt M. R. 

TITLE=Vibrational branching ratios and hyperfine structure of 11BH and its suitability for laser cooling

JOURNAL=Frontiers in Physics

VOLUME=2

YEAR=2014

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2014.00051

DOI=10.3389/fphy.2014.00051

ISSN=2296-424X

ABSTRACT=<p>The simple structure of the BH molecule makes it an excellent candidate for direct laser cooling. We measure the branching ratios for the decay of the A<sup>1</sup>Π (<italic>v</italic>′ = 0) state to vibrational levels of the ground state, X<sup>1</sup>Σ<sup>+</sup>, and find that they are exceedingly favorable for laser cooling. We verify that the branching ratio for the spin-forbidden transition to the intermediate a<sup>3</sup>Π state is inconsequentially small. We measure the frequency of the lowest rotational transition of the X state, and the hyperfine structure in the relevant levels of both the X and A states, and determine the nuclear electric quadrupole and magnetic dipole coupling constants. Our results show that, with a relatively simple laser cooling scheme, a Zeeman slower and magneto-optical trap can be used to cool, slow and trap BH molecules.</p>