We have been involved in CERN CLOUD-project since the beginning and have participated altogether 12 CLOUD experimental runs since 2007 (CLOUD 0 – CLOUD 11, with CLOUD 0 being a proof of concept run) summing up to approximately two years of experiment. CLOUD is likely the most well defined, most clean and by all means the best facility to simulate the atmospheric new particle formation. It has also a unique feature: we can utilise the high energy particle beam from CERN proton synchrotron. Why we do that? To simulate galactic cosmic radiation (GCR). GCR is the main source of ionisation in the atmosphere, and ions, may have a role in atmospheric new particle formation.
Up to date, we have measured nucleation (cluster formation) rates and the role of GCR in the cluster formation and growth in multiple different atmospherically relevant “chemical cocktails” and temperatures.
“Chemical cocktails” include sulphuric acid-ammonia, sulphuric acid – dimethyl amine, sulphuric acid – oxidised organics and oxidised organics alone. We have also been investigating the particle growth due condensation of highly oxidised low volatile organic vapours, just to mention few highlights.
Academy of Finland, European Commission 7th Framework Programme (Marie Curie Initial Training Network ‘CLOUD-ITN’ and ‘CLOUD-TRAIN’), and the European Research Council are acknowledged for funding the research.