Borexino SOX 2018The National Institute for Nuclear Physics (INFN) communicates the decision, commonly agreed with the Institute of Research into the Fundamental laws of the Universe (CEA/IRFU), to cancel the SOX project due to the technical impossibility of carrying out the experiment.
The Russian source producer, Mayak Production Association, has announced in December that it will not be able to deliver with the required characteristics the anti-neutrinos generator based on Cerium 144, at the core of the SOX project. Indeed the generator could not reach the required activity, by a factor 3, which means that it would not be able to provide enough anti-neutrinos nor  conduct the experiment in a scientifically effective and competitive way. The project, which was supported by two ERC (European Research Council) grants, the European funds reserved to highly innovative and challenging research projects, and which was part of the scientific program of the INFN Gran Sasso National Laboratories, will therefore not be realized.

"We knew that building a source of anti-neutrinos with the necessary characteristics to produce significant scientific results and internationally competitive was a technological challenge, - explains Marco Pallavicini, coordinator of the SOX project - but the great relevance of the scientific goal and the possibility of achieving it had guided us in this undertaking". "Today, unfortunately, we must accept the impossibility of producing a suitable source, - continues Pallavicini – this is a blow to me and to the many, especially young people, who believed in it and who worked with great commitment in recent years to bring SOX to realization". "Nevertheless this is how frontier research works: complex problems are tackled and cutting-edge technical and technological solutions are assessed. And sometimes it can happen that you have to face unexpected difficulties impossible to overcome. Our task as researchers is now to bet on new scientific targets with confidence," concludes Pallavicini.