The Institute of Astronomy with National Astronomical Observatory (IANAO) is the premier institute of astrophysics in Bulgaria, operating the National Astronomical Observatory, and the only one in Bulgaria engaged in radio astronomy (RA) and space weather (SW) research. It has recently taken a strategic decision to significantly expand its RA scientific arm, and to work towards adopting world-class radio observing capabilities. To this end, it has begun a collaboration with the Technical University of Sofia’s (TUS) Faculty of Telecommunications, a local expert institution with strong capabilities in phased antenna array communications. ASTRON is a world-class centre of RA science and technological development. DIAS is a world-leader in advanced astronomical studies and SW research. ASTRON and DIAS recognize the importance of a partnership with the IANAO for expanding the network of the advanced European distributed telescope LOFAR, as well as for enhancing its RA and space weather capabilities. The proposed “Scientific and Technological Excellence by Leveraging LOFAR Advancements in Radio astronomy” (STELLAR) project will address the goals of all four partners by significantly increasing the LOFAR technical and scientific expertise at TUS and IANAO. It will allow IANAO and TUS to develop and strengthen collaborations with ASTRON and DIAS. STELLAR is a major step towards the realization, utilization, and further development of a LOFAR station in Bulgaria. STELLAR will achieve its objectives through carefully planned trainings for IANAO and TUS staff at ASTRON and DIAS, including lectures, workshops, summer schools, and research staff exchanges. STELLAR will have a multiplicative effect for the Bulgarian astronomical and geophysical community as a whole through the development of RA, SW, and radio technology training curricula for Bulgarian scientists and engineers, thus ensuring a sustainable effect of the project.

Nuclear astrophysics studies the origin of the chemical elements: from the Big Bang, to stellar burning, and to neutron star mergers. ChETEC-INFRA networks the three types of infrastructures that, together, provide the capabilities needed for this quest: astronuclear laboratories supply reaction data, supercomputer facilities perform stellar structure and nucleosynthesis computations, and telescopes and mass spectrometers collect elemental and isotopic abundance data. ChETEC-INFRA will overcome existing barriers to progress: Specifically, we will unify access to nuclear astrophysics research infrastructures using a novel integrated web portal. We will develop improved nuclear reaction targets and detectors, open-source nucleosynthesis software tools, and three-dimensional model atmospheres for stellar spectral analysis based on up to date physics. We will pioneer complementary techniques to address the same science case, and we will link telescopes to nuclear labs and supercomputers. ChETEC-INFRA provides the community with the tools needed to address key questions on solar fusion, neutron capture nucleosynthesis, and explosive stellar processes. In a combined approach designed to facilitate and boost accessibility, synergies and training, the large amount of transnational access provided will enable projects exploiting at least two different types of infrastructures. Within ChETEC-INFRA, data are archived and catalogued for long-term sustainability beyond the end of the project, ranging from evaluated nuclear reaction rates to detailed abundance data for a multitude of stars to tracer nucleosynthesis calculations. ChETEC-INFRA will reach out to PhD students, secondary school students, and to the detector industry. The ChETEC-INFRA community builds on the success of the ChETEC COST Action CA16117 (Chemical Elements as Tracers of the Evolution of the Cosmos). ChETEC-INFRA is networked with the nuclear astrophysics communities in the United States, China, and Japan.