Cooling and collisions of large gas phase molecules

Abstract

Cold and dense samples of naphthalene (C₁₀H₈) are produced using buffer gas cooling in combination with rapid, high flow molecule injection. The observed naphthalene density is n ≈ 10¹¹ cm⁻³ over a volume of a few cm³ at a temperature of 6 K. We observe naphthalene–naphthalene collisions through two-body loss of naphthalene with a loss cross section of σ_– = 1.4 × 10⁻¹⁴ cm². Analysis is presented that indicates that this combination of techniques will be applicable to many comparably sized molecules. This technique can also be combined with cryogenic beam methods¹ to produce cold, high flux, continuous molecular beams.