Perspectives of Nuclear Physics in Europe - European Science ...

concentrate their efforts and continue to play a leading
role – provided sufficient computing resources are
made available.
Global Perspective
The recently inaugurated J-PARC complex of Accelerators
at Tokai (Japan) will be the most important laboratory
for hypernuclear physics in the next couple of years.
Another laboratory that will provide a good wealth of
experimental information on hypernuclear spectroscopy
is JLab. Several European groups are already involved in
experiments there. The European groups participating
in these efforts will take the chance to prepare for the
long-range programmes with PANDA at FAIR.
4.1.6 Recommendations
This report follows the tradition of similar documents written
in 2004 (NuPECC Long Range Plan 2004: Perspectives
for Nuclear Physics Research in Europe in the Coming
Decade and Beyond) and in 1997 (Nuclear Physics in
Europe: Highlights and Opportunities). Those earlier
reports emphasised the importance of understanding
hadronic physics on the basis of the underlying fundamental
theory of QCD. Extraordinary progress has been made
since the last report. The MAMI C facility in Mainz was
successfully installed and new, state-of-the-art detector
systems were added to COSY in Jülich and ELSA in Bonn.
Probing the nucleon structure by using lepton beams at
DESY and CERN yielded important results. Further studies
are going on at the COMPASS experiment at CERN.
This is complemented by the successful participation of
European groups in the Jefferson Laboratory’s hadron
physics programme. Frascati completed an ambitious
programme with the KLOE detector and on hypernuclear
physics. The construction of the FAIR facility, which the
2004 report recommended with the highest priority, is
taking more time than originally anticipated, because of
its international nature, which required lengthy political
processes. Theory also progressed significantly in both
fields – the simulation of hadron physics on the computer
and the development of phenomenological theories on
the basis of QCD. Given this progress and promise it
holds, three recommendations emerge naturally for the
near- and mid-term future and a fourth one for the longer
term perspectives of the field.
First recommendation:
A speedy construction of the PANDA experiment at
FAIR should be given the highest priority in the near and
mid-term future. Surprising new results in recent years
point to exciting physics hidden in the strong interaction,
waiting to be understood and explored with antiprotons
at FAIR. PANDA has a sophisticated detector system that
allows for a broad, diverse physics programme capable
of delivering results on hadron spectroscopy, the
nucleon’s structure, hypernuclei and in-medium modifications
of hadrons, which cannot easily be achieved
otherwise and therefore represent a major step forward
in our understanding of strong interaction physics. As a
flagship experiment for hadron physics, PANDA not only
enjoys the involvement of most of the hadron physics
community in Europe, it also attracts participants from
countries outside Europe and thus fulfils the aim of FAIR
to be a truly international facility.
Second recommendation:
Complete and exploit currently operating facilities
to ensure the best use of the investments made in the
past. These running facilities ensure high-quality physics
output while FAIR is being constructed. The users come
mainly from universities that combine education and
research in an ideal fashion. Continuing research at current
facilities provides an excellent training environment
for the future scientific workforce in Europe. Of course
there must be a balance between this recommendation
and the funding and work force requirements of the other
recommendations listed here.
Third recommendation:
Continued support for theory that aims to understand
hadrons in terms of the fundamental degrees of freedom
of QCD. Especially important in hadron physics is the
close interplay between theory and experiment, which
requires strong support for theoretical efforts. The computational
(lattice) and phenomenological approaches
complement each other and both are required to ensure
progress in the future.
Fourth recommendation:
In the longer term, further detailed studies of the
quark-gluon structure of hadrons will require additional
dedicated facilities. FAIR offers two options to contribute
to this international effort: the upgrade of the HESR
facility to a polarised proton-antiproton-collider or
to a polarised electron-proton/ion collider. Detailed
studies for both set-ups should be supported. Gluon
density saturation in hadrons will best be investigated
at the Electron-Ion Colliders (EICs) planned in the USA
or at the LHeC, a possible future accelerator complex
using the LHC at CERN.
General remarks:
Hadron physics is at the interface of elementary particle
physics, which deals with pointlike particles in
the high-energy limit, and the world around us, composed
of richly structured objects that are built out of
those fundamental particles. The complex problem of
understanding hadrons and ultimately nuclei requires a
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