LIP celebrates the 20th anniversary of the Neutrinos group

José Maneira has long since lost count of the neutrino interactions he has observed, but back in the 1990s, he wanted to study the subject and “there was no one working on it in Portugal”. As always, the gap gave rise to an opportunity: with the help of Professor Amélia Maio, the then student at the Faculty of Sciences of the University of Lisbon (Ciências ULisboa) discovered in Milan one of the centres of Italy’s National Institute of Nuclear Physics – and it was there that he carried out various pieces of work for his master’s and doctoral degrees. After spending time at Queen’s University in Canada and working with Art McDonald before he won the Nobel Prize in Physics, he returned in 2005 and had a research project approved by the Laboratory of Instrumentation and Particle Physics (LIP). It could have marked the launch of the Neutrino Physics Group, but the professor from the Department of Physics offers a perfectly plausible reason why this Group only celebrated its 20th anniversary this Tuesday at LIP, retaining 2006 as the reference year.

“LIP accepted and encouraged this first research project I submitted, but in 2005 I was the only one working in this field at LIP. And there are no one-person research groups. It was only in 2006 that researchers such as Sofia Andringa and Nuno Barros joined… and Professor Amélia Maio began working more closely with this new group at LIP,” explains José Maneira, a national pioneer in the field and coordinator of the Neutrino Physics Group (GFN) at LIP.

Despite the efforts of scientists from various continents, neutrinos remain among the most mysterious elementary particles. There had already been theoretical research on neutrinos in Portugal, but the early career of José Maneira ended up helping to pioneer the experimental side, whilst also contributing to a new positioning of Ciências ULisboa as a pioneering institution. “The first three PhDs in Experimental Neutrino Physics in Portugal were completed at Ciências ULisboa. I completed my PhD in 2002; Nuno Barros followed in 2012, and in 2022 it was Ana Sofia Inácio’s turn. Ciências ULisboa leads the way in experimental neutrino physics at a national level,” recalls the professor from the Department of Physics.

The days when PhDs were completed only once every ten years are now a thing of the past, and José Maneira estimates that, before the end of this year, another PhD thesis in the field of Experimental Neutrino Physics is set to be completed, alongside others that are already taking shape and may be announced in the near future. Meanwhile, Nuno Barros has taken up a teaching post at the University of Minho and “it is only natural that more PhDs will emerge there in the near future”.

The celebration of the GFN’s 20th anniversary served to highlight some of the pioneering work carried out in Portugal and also had the honour of welcoming an internationally renowned figure: Mark Chen, a professor at Queen’s University, came to Lisbon to present the SNO+ project, which aims to collect data on interactions with neutrinos – particles known for their ability to pass through matter and for being among the most abundant in the Universe. In addition to Mark Chen’s presentation on the SNO+ project, José Maneira himself provided details during the GFN’s 20th anniversary about the DUNE project, which aims to build an infrastructure designed to detect changes in the nature of a neutrino as it travels underground between the Fermilab laboratory in Illinois and the Sanford laboratory in South Dakota, in the United States.

Both DUNE and SNO+ serve as examples for José Maneira to illustrate how Ciências ULisboa and LIP have been involved in cutting-edge projects. At SNO+, which is preparing an experiment related to a rare decay of a tellurium isotope, LIP teams have contributed to the development of calibration equipment and data analysis. “Some tellurium decays result in the release of two electrons and two neutrinos. If we find that no neutrinos were released in these decays, we can deduce that the neutrinos annihilated each other, meaning that neutrinos are not fundamentally different from antineutrinos after all. And right now, that is the big question facing this field worldwide,” says José Maneira.

In the DUNE project, LIP’s involvement began with the development of calibration equipment – and here too, the pioneering nature of the research could make all the difference.

José Maneira points out that DUNE aims to alternately emit beams of neutrinos and antineutrinos to observe the changes both types of particles undergo as they travel a 1,300-kilometre underground path.

“It is an important project because it may provide clues about the asymmetry between matter and antimatter. Today, we have a universe dominated by matter… so the question that arises is: where has the antimatter gone? That is the question that may be answered if we use antineutrinos as the antimatter counterpart of neutrinos,” he explains.

The professor from the Department of Physics has no doubt that the subject may prove particularly interesting for those wishing to pursue master’s or doctoral degrees that allow them to participate in international projects at the forefront of research.

“It is an exciting field because it keeps fundamental questions open that may not take long to answer through projects such as SNO+ and DUNE… in which Ciências ULisboa is participating!” says the neutrino specialist. “Without Ciências ULisboa and without LIP, experimental neutrino physics would not be the same in Portugal. This is an area in which Ciências ULisboa will continue to lead,” concludes the researcher.