While the internal structure of hadrons and the spectra of their excited states are important aspects of QCD, it is at least equally important to understand how nuclear physics emerges in a more rigorous way out of QCD and how nuclear structures - nuclei on the small scale and dense stellar objects on the large scale - are formed.

The study of hypernuclei can illuminate features that are obscured in conventional nuclear systems. The hyperon offers a selective probe of the hadronic many-body problem as its insertion inside nuclei is not restricted by the Pauli principle. Significant progress in nuclear structure calculations in chiral effective field theory nurtures the hope that detailed information on excitation spectra of hypernuclei will provide unique information on the hyperon-nucleon and hyperon-hyperon interactions. At the same time, the L-N and L-L weak interaction can be studied via hypernuclei decays, opening a unique window for the four-baryon, strangeness non-conserving interaction. Furthermore, the physics of strangeness in hadronic systems is a constantly developing field. It brings up new, often unexpected results, new challenges and open questions like S-hypernuclei, kaonic nuclei, exotic hadronic states like the controversially discussed pentaquark baryons and the H-dibaryons.

Even though a number of new experimental techniques have been developed in this field in the last decade, our knowledge is still limited to a small number of hypernuclei on or near the b-stability line. Several activities which are planned in Europe (High resolution g-spectroscopy in FINUDA, KAOS/A1@MAMI, HYPHI@GSI, PANDA@FAIR) for the next years will focus on different observables thus helping to overcome the present limitation. The Network Activity Strange Particles in Hadronic Environment Research in Europe (SPHERE) is created to support the exchange of new ideas and technologies, to tighten the relations among the various experimental and theoretical research groups and thus to broaden and complement the existing and future research structures in Europe.

The program of SPHERE consists of four activities: Physics (PHY), Experiments (EXP), Detectors (DET) and Theory (THE).

·         PHY: The close collaboration between various theory groups and experimentalists will help to guide and define the goals of future experiments and it will help to focus on the most relevant physics issues. Intensive and frequent scientific contacts between all participating groups will ensure a coordinated research program.

·         EXP: The planning, analysis and interpretation of the hypernuclear experiments require detailed input from very different branches of physics, ranging from high energy nuclear reactions, atomic transitions in hyperatoms, nuclear capture, nuclear physics up to hadron physics. A joint effort between theoreticians and experimentalists will ensure an optimal solution for the complex scientific and technological challenges in the analysis of present and the planning of future experiments.

·         DET: Exchange of knowledge to develop, build, integrate and operate the required new experimental equipment and analysis tools. Sharing of complex experimental devices will create synergetic effects and open new experimental possibilities.

·         THE: This activity will serve to join efforts of the various theory groups with the common goal to develop theoretical methods appropriate for the analysis of hypernuclear production and structure data, including large-scale numerical simulations. An issue of central importance is to derive elementary baryon observables from the hypernuclear data and investigate their relation and application to fields outside SPHERE, especially to hadron physics and astrophysics.

The physics activity (PHYS) comprises four tasks:

·         Exploring the role of weak decays in various nuclei which are accessible in future experiments

·         Exploring the physics potential of S = -2 and S = -3 systems

·         Feasibility study for PANDA

·         Exploring the role of elementary processes for the production of hypernuclei in nuclear reactions

All groups will participate in this activity.

The experimental activity (EXP) comprises three tasks:

·         Development of a Monte Carlo code based on detailed physics input for the experiments

·         Optimization of experimental setups for the various experiments

·         Development of common analysis strategies and tools

The main contributions will come from UMainz, INFN-Catania, INFN-LNF,INFN-Torino and GSI.

The sub-tasks of the detector activity (DET)are listed below:

·         Optimization of the HPGe-detector setups in the FINUDA and PANDA experiments

·         Optimization of the experimental setup and the tracking trigger in KAOS/A1 and HYPHI

·         Development of a fiber detector with SiPM-readout for KAOS/A1 and PANDA

·         Final design and prototype production for KAOS/A1 and PANDA detectors

The main contributors to this activity will be INFN-LNF, INFN-Torino, INFN-Catania,GSI, UMainz and JLU.

The sub-tasks of the theoretical activity are:

·         Relation of weak decay of hypernuclei to fundamental processes of QCD

·         Relation of hypernuclear observables to the free baryon-baryon force in SU(3)

·         Strange mesons in hadronic systems(antikaonic systems)

·         Application of hypernuclear physics to other fields of physics

The contributions will come from UB, JLU, University of Granada, Hebrew University, NPI-Prague, Universita' di Torino, University of Valencia and Copernicus Astronomical Center Warsaw.

·         yearly progress reports of the experimental and theoretical activity of SPHERE

·         technical reports on the various scientific programs e.g. design report and feasibility studies

·         detailed proposals for future experiments at FINUDA, KAOS/A1, HYPHI and PANDA

·         publications in scientific journals

Annual workshops will be held by SPHERE, with the aim of bringing together scientists and students with complementary expertise for an extended period of time. These extended annual meetings of the whole SPHERE community will help to share and disseminate the achievements of the Network both within and outside the Network. Progress reports will be delivered on a regular basis, usually following the annual workshop.

In addition, there will be subgroup meetings of the participating institutions of SPHERE during the frequent collaboration meetings of the various experiments which will guarantee a steady information flow among the participants of SPHERE. Theoreticians participate and contribute to these meetings.

The results of the Network will be promoted by formal and informal meetings, scientific and popular presentations, websites and new and emerging electronic media.

Publications in scientific journals are hard to predict. Considering the publication records of the participating groups, however, it is expected that the publication of the scientific results of SPHERE will be a continuous process after a startup phase.

Technical reports will be delivered after finishing a feasibility study. The time for the submission of proposals is difficult to predict. We do, however, expect that several detailed proposals based on the SPHERE activity will be presented within its funding period.

The impact of SPHERE in hadronic physics is the improvement of the relations of the participating groups to the four relevant European experimental facilities (FINUDA@DAPHNE, KAOS@MAMI, HYPHI@GSI, PANDA@FAIR) and of the theoretical groupsto the selected physics topics given above. It is expected that the Research Infrastructures as well as the other institutions involved in this Network will significantly profit from its outcome.

Research at the frontier of our knowledge provides also optimal conditions for the training of excellent students and future scientists. The education of the large number of graduate students participating in SPHERE is therefore another important aspect.