Projects / Programmes
January 1, 2015
- December 31, 2021
| Code |
Science |
Field |
Subfield |
| 1.02.00 |
Natural sciences and mathematics |
Physics |
|
| Code |
Science |
Field |
| P002 |
Natural sciences and mathematics |
Physics |
| Code |
Science |
Field |
| 1.03 |
Natural Sciences |
Physical sciences |
ultra high energy cosmic rays, hadronic interactions at extreme energies, gamma ray astronomy, black holes, new physics
Researchers (26)
Organisations (2)
Abstract
The proposed program is oriented towards the studies of processes at the extreme energy scales in nature. Its main goal is to push the frontier of knowledge regarding the ultra-high energy cosmic rays (UHECR), very-high energy (VHE) gamma rays and elementary particles. The proposed activities are embedded into the work of international research collaborations Pierre Auger, CTA and Belle2.
UHECR research will be pursued within the P. Auger Collaboration. Its work has insofar led to major breakthroughs, such as the evidence of a strong suppression of the UHECR flux above 55 EeV, anisotropy of their arrival directions, and tight limits on the UHE photon and neutrino fluxes. Major open questions that remain, such as particle composition of the UHECR flux and the identity of their sources, will be studied in detail in the scope of the proposed program. For this purpose, the Auger observatory will be substantially upgraded and will provide information on muon contents of the extensive air showers, which will facilitate identification of the primary UHECR. We will take an active role in the science and upgrade activities, focusing on the composition and anisotropy studies of the highest-energy particles.
The research of very high energy (VHE) gamma-rays will be pursued within Cherenkov Telescope Array (CTA) Consortium. Gamma-rays that are produced as secondaries in the UHECR acceleration and in the inelastic interactions during their propagation are not affected by interstellar magnetic fields and can be used to trace back to the location of UHECR sources. CTA Consortium will build two observatories for VHE gamma-rays providing full-sky coverage, improved sensitivity, angular and energy resolution with respect to current experiments. Scientific activities, scheduled to begin with partial array in late 2016, are expected to bring significant progress to the studies of cosmic ray sources, acceleration mechanisms, gamma-ray interactions with interstellar medium, as well as the nature and variety of black hole particle accelerators. In addition, due to its superior sensitivity, CTA will serve as a tool in dark matter search, Lorentz invariance violation and other fundamental physics tests.
The proposed scientific goals of both Auger and CTA collaborations will be supported and complemented by theoretical studies in quantum gravity, focusing on string theory, which is currently the most promising candidate for a unified quantum theory of particle physics and gravitational physics. Another complementary activity will be pursued through our involvement in the Belle2 experiment, probing "new" physics with precision measurements of B meson decay properties.
Significance for science
The goal of the proposed program is to investigate the phenomena related to extreme energy scales in nature. Its activities are embedded into the work of international research collaborations with competent partners, including among others the institutions from the EU, USA, Brazil, Argentina and Japan. Its results will be of fundamental nature and are expected to be relevant for science in general and in particular for the fields of astro- and elementary particle physics, astrophysics and cosmology.
The research of ultra-high energy cosmic rays (UHECR) and their interactions in the Earth's atmosphere (at several 10's of times higher energies than the projected final energies of the LHC collider) is at the forefront of the global physics endeavors in fundamental science. It is a fact that ultra high energy cosmic rays are the most energetic particles in nature, and that collisions at those energies may, with present technologies, never be achievable in man-made particle colliders. Analysis and interpretation of UHECR data collected by the Pierre Auger Observatory may be more difficult than that for data collected at accelerators, but due to its uniqueness provides all the more a challenge to the research community. A related activity is the investigation of very-high energy (VHE) gamma rays. As they travel in a straight line from their source to an observer, unscrambled by magnetic fields, they may provide the key to the identification of VHE gamma-ray and UHECR sources, which are expected to be related. Our involvement in the CTA project, an initiative to build the next generation ground-based very high energy gamma-ray instrument, is a step towards that goal. CTA is expected to provide a deep insight into the non-thermal high-energy universe.
The above activities will be strongly supported and complemented by theoretic studies. The understanding of black holes and the early universe has undergone dramatic progress in recent years, especially due to results coming from various experiments such as Fermi-LAT. It is a very exciting moment for the study of quantum gravity, black holes and cosmology, as a result of these experiments. For the first time there is some real data that enables us to eliminate various inaccurate models and focus on the more promising ones. There is great hope that in the next few years dramatic progress will be made in this fundamental field of study, of great importance for the development of science.
Recent experimental results in the field of elementary particle physics are rising new questions about the existence of new physics beyond the established Standard Model of elementary particles and interactions between them. We will pursue one of the ways to push the knowledge frontier through our activities in Belle2 collaboration, measuring the properties of B meson decays originating from electron-positron collisions at unprecedented luminosity, and, unlike the LHC, with a low level of background processes. Possible outcomes of these searches may, among others, include a discovery of a new mechanism at a higher energy scale, responsible for the observed CKM matrix hierarchy, and a better insight into the problem with the matter-antimatter asymmetry in the universe, which can not be explained solely by the CP violation within the Standard Model.
Finally, the proposed research program is relevant for integration into research roadmap and research projects of EU, as the largest financial and manpower contributors for the foreseen Pierre Auger Observatory upgrade and the future Cherenkov Telescope Array are institutions from EU. For both observatories our activities within the group will be coordinated with these institutions and oriented towards applying for European projects in the framework of Horizon 2020 and other relevant European mechanisms.
Significance for the country
Direct impact of the proposed program on the economy and society arises through the possibility of a transfer of knowledge and state-of-the-art technologies, developed for use at international research collaborations (i.e. the Pierre Auger Observatory - PAO), to Slovenia for commerical use and public service, a task in which we have been actively pursuing since our initial involvement with PAO.
As a direct spin-off of the basic research at PAO (characterization of the atmosphere as the main detector media using Lidar technology, timing of the ground detector array using GPS signals) the Laboratory for Astroparticle Physics of the University of Nova Gorica (together with its Center for Atmospheric Research and the Slovenian Environmental Agency) constructed the first lidar observatory site in Slovenia at Otlica, which among others successfully tracked and characterized Icelandic volcanic ash in 2010 Eyjafjallajökull eruption. We independently developed a Raman lidar system for the remote profiling of water vapor concentrations in the atmosphere, and in collaboration with the Slovenian companies Optotech and Fotona we have also developed a mobile lidar for aerosol tracking and identification. We are also investigating the impact of ionospheric perturbations on GPS and the posibilities of their mitigation, which were at low latitudes found to be of considerable importance in the times of the coming solar maximum. All these devices provide not only scientific results but also results with a broader impact on society. At the present we are in the negotiation phase with business partners to transfer this knowledge and technology into products for commercial use. These activities will be expanded and intensfied in the scope of the proposed project.
As an indirect impact of the proposed program on society we highlight the active and competitive participation of Slovenian researchers and students in these leading-edge global research activities; success of this and other such projects will help ensure the recognition of Slovenia as a high technology oriented country, which would further stimulate and promote international scientific, economical and financial cooperation.
The proposed program will facilitate the transfer of knowledge at the leading edge of current global research activities and state-of-the art technology into Slovenia, and in particular, it will provide a deeper insight into the description of fundamental interactions that govern our world, including gravity. Results are expected to bring indirect benefits on many levels of social activities, including on a cultural level and a technological level, as a profound understanding of nature inevitably leads to the development of tools beneficial to the society and the humankind as a whole.
Most important scientific results
Annual report
2015,
interim report
Most important socioeconomically and culturally relevant results
Annual report
2015,
interim report
