Code comparisons and benchmarking with different SEY models in electron cloud build-up simulations

A number of computer codes has been developed in laboratories worldwide to simulate electron cloud formation and dissipation in accelerators. The codes’ underlying assumptions and physical models are often different and based on alternative experimental inputs. As part of an inter-laboratory code-code and code-experiment benchmarking effort re-launched after the ECLOUD’04 workshop [4], the present study explores the effect on simulation results of a reference case of using different descriptions of secondary emission properties for electrons impinging on the vacuum chamber walls. The two models currently used in the codes ECLOUD [5, 6] and POSINST [7, 8] (and described respectively in [1] and [2]) have been compared, along with some tentative phenomenological fits of recent laboratory measurements obtained in surface science experiments realised at CERN [3].