The European Spallation Source ERIC (ESS) is a multi-disciplinary research facility currently under construction[1] in Lund, Sweden.

[7] The ESS will assist scientists in the tasks of observing and understanding basic atomic structures and forces, which are more challenging to do with other neutron sources in terms of lengths and time scales.

During operation, the ESS will use nuclear spallation, a process in which neutrons are liberated from heavy elements by high energy protons.

This is considered to be a safer process than uranium fission since the reaction requires an external energy supply which can be stopped easily.

It operates similarly to optical fibres, directing the beams of neutrons to experimental stations, where research is performed on a range of materials.

Neutrons serve as a probe for revealing the structure and function of matter from the microscopic down to the atomic scale, with the potential for development of new materials and processes.

By 1993, the European Neutron Scattering Association began to advocate for the construction of a new spallation source, and the project would eventually become known as the ESS.

So much so that the Organization for Economic Development (OECD), declared in 1999 that a new generation of high-intensity neutron sources should be built, one each in North America, Asia and Europe.

In 2001, a European roadmap for developing accelerator driven systems for nuclear waste incineration estimated that the ESS could have the beam ready for users in 2010.

[16] A European international task force gathered in Bonn, Germany in 2002 to review the findings and a positive consensus emerged to build ESS.

The stakeholders group met a year later to review the task force's progress, and in 2003 a new design concept was adopted that set the course for beginning operations by 2019.

The Founding Members of the European Spallation Source ERIC are the Czech Republic, Denmark, Estonia, France, Germany, Hungary, Italy, Norway, Poland, Spain, Sweden, Switzerland and the United Kingdom.

After 10 years of data collection, ESSnuSB is expected to cover over 70% of the CP-violating phase range with 5σ confidence level, achieving a precision better than 8° for all δCP values.