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Periodic Reporting for period 2 - InvisiblesPlus (InvisiblesPlus)

Período documentado: 2018-02-01 hasta 2020-01-31

NEUTRINOS (Ns) and DARK MATTER (DM) are the most abundant particles in the universe. Their couplings to ordinary matter are so tenuous that they remained undiscovered -invisible- until very recently. N masses and DM constitute the first evidence ever of physics beyond the Standard Model of particle physics. The path to build the New Standard Model must confront the fundamental nature of the particles in the invisible sector at large. Furthermore, for each particle there is a mirror image with identical mass and opposite charge(s): its antiparticle. The laws of physics are almost particle-antiparticle symmetric: an asymmetry in Ns and/or DM properties may be the required seed that explains why the universe is made of matter and not antimatter.
InvisiblesPlus Project was the first transnational program addressing the N and DM properties at large, their interfaces, and in addition the connections of their particle/antiparticle asymmetries with those of the visible universe. It also complemented, continued and specially extended to a new qualitative realm the knowledge sharing and long-term collaboration of the well-established ITN Invisibles. The public engagement was also focused on the societal impact of research, showing that investments in science imply technological innovations which are essential not only for science but also for the benefit of society at large. The main deliverable of InνisiblesPlus was the scientific results that improved our understanding of the most abundant particles in the universe, that is, N and DM. A complementary search was that of the origin of the mass of ordinary particles, at the heart of the LHC and other hadronic enterprises. The world-wide collaborations among the leaders in the field planned within RISE constituted the best warranty that the results obtained are of high quality and constitute a significant step ahead in this quest. The strong dissemination strategy of the project aimed at increasing the impact of these scientific results.
This project was organized around the physics of N and DM (WP1 and WP2), with focus on the determination of their parameters and properties, and also on the crucial question of the identity of those particles and antiparticles and their different behavior beyond what stems from their opposite charges (technically dubbed “CP violation”). A third special WP (WP3) was dedicated to the fundamental symmetries of nature while the fourth research WP (WP4) developed the complementarity between N and DM physics.
The scientific progress of the project has been excellent. The network produced a large number of scientific publications in the area of Neutrino physics and Dark Matter. These were published in high impact journals in the field. Secondments were key to achieve the scientific goals of the project. In addition to developing already established collaborations for the task of InvisiblesPlus, they foster new scientific exchanges and new collaborations. Several new projects were stemming out of secondments. Word-leading laboratories were associated to the network. This was very important for all our ESRs and ERs working on Neutrino/DM phenomenology (and experiments) to be able to spend some time in these facilities, this allowed the direct interaction between theorists and experimentalists, leading to novel ideas, more reliable and detailed phenomenological studies. The secondments have contributed so far rather uniformly for all Work Packages. The balance between EU vs non-EU based secondments was crucial for the broad physics program of the network.
Good progress has been achieved towards the objectives to all WPs. In WP1 Neutrinos, several secondments at Fermilab and CERN have been essential to establish the links to the DUNE projects and the CERN Neutrino Platform. Regarding WP2 Dark Matter, secondments at the Korea Institute for Advance Studies and the HEP Chinese Academy of Sciences have led to fruitful collaborations on various topics. On the other hand, in WP3 BSM and the fundamental C, P, T Symmetries, secondments at CNRS, INFN, U. of Berkeley and CERN have resulted in collaborations on these topics. Finally, in WP4 Interfaces with secondments at CNRS, INFN, U. of Tokyo, U. Southampton and U. Washington.
InvisiblesPlus had a rich outreach plan. Specific actions have been identified in a coherent program which aimed at reaching a wide and varied public, raising its awareness to the research conducted by the project, its societal impact, and contributing to policy making at a critical decision time. The Invisibles18 Workshop took place in Karlsruhe, Germany from September 3 to September 7, 2018 and was organized by the MPG node in collaboration with the Karlsruhe Institute of Technology with 146 participants from 26 countries. The Invisibles19 Workshop was organized by UVEG with 162 participants from 23 countries.
Among the building blocks of the Universe, Neutrinos (Ns) and Dark Matter states (DM) are the most abundant of particles, yet they remained unnoticed -invisible- for a long time because of their tenuous couplings to the ordinary matter that we are composed of. Neutrinos are the best messengers of the dark sectors of the universe (dark matter and dark energy), as their interactions are not obscured by strong or electromagnetic forces. Most of the matter in the Universe seems to be neutral, does not interact with light and therefore is called “dark”. It is likely that neutrinos constitute only a fraction of dark matter. The nature of the bulk of the dark matter and its interactions, other than gravity, remains unknown, even though energetically dark matter adds to more than 20% of the universe. The discovery of neutrino oscillations and of DM cannot be explained within the Standard Model of particle physics (SM); they constitute the first clues of particle physics beyond the SM (BSM), awaiting to be revealed. Understanding the laws of physics accounting for neutrinos and DM is one of the major and most pressing unsolved questions in science today.
Secondments played a very important role in enhancing the scientific standing and international visibility of the ESR and more junior ERs in the network. In addition to being exposed to a new research environment and to starting new scientific collaborations, the researchers gave seminars at the hosting institutions. They also were mentored by additional senior scientists and attended many activities not available at their sending node. This results in an enhanced scientific growth of the ESRs and ERs but also in tangible impact on their careers. In science, women represent a small fraction of researchers and moreover that fraction decreases with the seniority, with only few women at the professor level in Europe and worldwide.
InvisiblesPlus provided scientific keys and complementary skills, international visibility, and collaborative links required to pursue a successful career in science or industry. Indeed, attention was devoted to fostering a stronger participation in science also of less-represented groups: in particular, the high-quality institutional partners from developing and emergent countries were an excellent asset for it. The outreach activities carried out and planned were strengthening this aspect by making sure those women and less represented groups in the specific environment were involved in the activities and gave them high visibility.
Invisibles16 Workshop
Prof. Kajita gave a talk at Invisibles16 Workshop_Padova