Cooling and Collisions of Large Gas Phase Molecules

Abstract

Cold and dense samples of naphthalene \((C_{10}H_8)\) are produced using buffer gas cooling in combination with rapid, high flow molecule injection. The observed naphthalene density is \(n \approx 10^{11} cm_{−3}\) over a volume of a few \(cm^3\) at a temperature of 6 K. We observe naphthalene–naphthalene collisions through two-body loss of naphthalene with a loss cross section of \(\sigma_{\Lambda-\Lambda} = 1.4 × 10^{-14} cm^2\). 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 methods to produce cold, high flux, continuous molecular beams.