title: High-resolution imaging of velocity-controlled molecular collisions using counterpropagating beams.
abstract: We present ultrahigh-resolution measurements of state-to-state inelastic differential cross sections for NO-Ne and NO-Ar collisions, obtained by combining the Stark deceleration and velocity map imaging techniques. We show that for counterpropagating crossed beam geometries, the effect of the velocity spreads of the reagent beams on the angular resolution of the images is minimized. Furthermore, the counterpropagating geometry results in images that are symmetric with respect to the relative velocity vector. This allows for the use of inverse Abel transformation methods that enhance the resolution further. State-resolved diffraction oscillations in the differential cross sections are measured with an angular resolution approaching 0.3°. Distinct structures observed in the cross sections gauge the quality of recent ab initio potential energy surfaces for NO-rare-gas atom collisions with unprecedented precision.
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Sjoerd N
authors.initials: SN
authors.lastname: Vogels
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Jolijn
authors.initials: J
authors.lastname: Onvlee
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Alexander
authors.initials: A
authors.lastname: von Zastrow
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Gerrit C
authors.initials: GC
authors.lastname: Groenenboom
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Ad
authors.initials: A
authors.lastname: van der Avoird
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
authors.forename: Sebastiaan Y T
authors.initials: SY
authors.lastname: van de Meerakker