Researchers from Chalmers tekniska högskola, Lund University, Stockholms universitet and Uppsala University met with ESS this week to continue planning for a new Sweden-led instrument. The instrument, called HIBEAM, will search for neutrons converting into anti-matter or invisible particles belonging to a hidden "dark" sector. Investigations using an instrument such as HIBEAM will be able to address puzzling questions in modern physics. These include explaining why antimatter is so rare compared to matter and identifying the composition of dark matter, the universe's mysterious "missing matter". The unprecedented brightness and other experimental conditions at ESS will allow HIBEAM to exceed the sensitivity of previous research by an order of magnitude. While the focus of HIBEAM is the development of a dedicated fundamental physics beamline, it could also be the first stage of an even more ambitious ESS upgrade program involving the investigation of neutrons converting to antimatter - with a sensitivity improvement of a factor of 1000. The work is funded by a 10MSEK award from the Swedish Research Council and is led by Professor David Milstead, Stockholm University. It involves design studies and the construction and testing of a detector prototype. The work is expected to lead to conceptual design report for HIBEAM at the end of 2023.