Research at ECT* has been recognized with two journal covers in the month of September 2023

An international collaboration involving the University of Warsaw (Poland), and funding from the European Union through the EURAMET initiative, performed a first principle calculation of the third density and acoustic virial coefficients of helium with unprecedented accuracy, vastly exceeding the one achievable in experiments, and improving it by a factor of five on the previous analogous calculation.

These results have been reported in Physical Chemistry Chemical Physics. They are expected to have significant impact on temperature and pressure metrology, enabling more accurate primary standards and consolidating a paradigm shift by which ab initio thermophysical data are crucial for establishing the state-of-the-art accuracy of gas-based primary standards of temperature and pressure.

This work is the culmination of several years of investigation, involving many research groups and metrological institutes in Europe (INRiM in Italy, PTB in Germany, LNE-Cnam in France, and NPL in the UK) and the United States (NIST). These endeavors, which have been characterized by a fruitful interplay between experimental and theoretical advances, have recently been reviewed in another paper published in the Journal of Physical and Chemical Reference Data. The  importance and usefulness of these results has also been recognized by the journal editor who made it a Featured article and used it to illustrate the cover of a special collection devoted to the latest research in temperature metrology.