title: Observation of mixed fermionic-bosonic helium clusters by transmission grating diffraction.
abstract: Small weakly bound boson-fermion 4He(m) 3He(n) clusters formed in a free jet expansion are identified using nondestructive transmission grating diffraction. The observations confirm the existence of more than 11 very tenuous complexes including the three-body halo molecule 4He2 3He and the pseudo-Borromean complex 4He2 3He2. Effective cluster formation temperatures, extracted from a sudden freeze model for cluster growth using theoretical binding energies, increase smoothly with cluster size, thereby confirming the calculations with the possible exception of 4He2 3He2.
authors.affiliation: Max-Planck-Institut für Dynamik und Selbstorganisation, Bunsenstrasse 10, D-37073 Göttingen, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Kalinin
authors.forename: Oleg
authors.initials: O
authors.lastname: Kornilov
authors.forename: Wieland
authors.initials: W
authors.lastname: Schöllkopf
authors.forename: J Peter
authors.initials: JP
authors.lastname: Toennies