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

technology), a three-dimensional architecture based on
enhanced Cell BE processors, with an aggregate peak
performance of more than 416 (208) teraflop/s in single
(double) precision will become operational in the near
future. For a petaflop/s performance utilising the full
capacity of the next generation of multi-core processors,
a more powerful communication network needs
to be developed. In this respect, the apeNEXT computer
initiative at the European level was remarkable. For
thermodynamics calculations, with moderate demand
on computer memory and communication, high-end
graphic cards (GPUs) promise to be a powerful alternative
to massively parallel architectures. Similar strategies
are followed for the next generation of high-level trigger
architectures foreseen to be used for FAIR or for future
high luminosity LHC experiments, where rare events
of interest must be selected on-line in a collision rate
environment up to 10 9 times higher. Interpretation of the
experimental results in terms of fundamental properties
of matter requires sophisticated modelling of the collision
dynamics based in principle on three-dimensional
viscous relativistic dynamics followed by hadronic
Boltzmann transport calculations. Such large-scale
calculations can be efficiently performed on computing
infrastructures of the GRID type.
Network of Excellence – When the nuclear physics
community embarked on relativistic and ultra-relativistic
heavy ion collisions, R&D activities were started at
the European level. Over the years, the community has
built up a real network of excellence of infrastructures
and expertise across Europe. This network has had a
major impact on the development of high performance
detection and identification methods, associated frontend
electronics, building important parts of large-scale
experiments, structuring distributed computing centres
as part of large-scale GRID infrastructures and physics
programmes of the associated international collaborations.
This unique achievement has to be consolidated
to secure its contribution for running the experiments,
for fully exploiting their physics potential as well as for
the preparation and construction of future experimental
facilities. In this respect, the former initiative of IUPAP to
produce a compendium of European facilities involved in
research activities along Nuclear Physics key issues must
be continued and extended to the level of a European
Network of Excellence, as a component of the largescale
infrastructures network. Based on well-defined
criteria, on-line monitoring and regular evaluation of its
components, such a network can serve as an expert
panel for governmental or inter-governmental organisations
to secure their financial support and promote the
field of nuclear physics on an international level.
4.2.7 Recommendations
1) The understanding of the properties of the Quark
Gluon Plasma requires the full exploitation of the
unique new energy regime opened up by the LHC
at CERN. Support for a comprehensive physics programme
with proton-nucleus and nucleus-nucleus
collisions at several energies and upgrades of
the ALICE detector must be assured. This entails
a long-term investment in a vigorous programme with
nuclear beams at the highest possible luminosities for
the next decade. In addition, a proton-nucleus collision
programme must be pursued to provide access to the
physics of gluon saturation and to elucidate the interplay
between cold nuclear matter effects and genuine
plasma features. A programme of focused upgrades of
the ALICE detector at LHC must be developed to further
extend the physics reach into kinematically presently
unexplored and unavailable regions.
2) The construction of the FAIR accelerators and
the CBM experiment must be strongly supported
in order to open up in order to enable the study of
matter at extremely high baryonic densities. Such
studies will shed light on the nature of the phase transition
to a Quark Gluon Plasma and on the existence of a
critical point in the phase diagram of matter that interacts
via the strong interaction. Progress will be driven by
experiments at the SPS, at SIS100 and SIS18, operating
at the highest luminosities. The future high-intensity
beams from SIS-300 coupled with a detector capable
of operating at very high rates will provide access to
rare probes.
3) Experiments using beams of rare (n-rich and
n-poor) isotopes are essential for understanding
the isospin properties of nuclear matter and the
nuclear liquid gas phase transition and require the
construction and use of FAIR and SPIRAL2 (with the
energy upgrading). Suitable beams in an energy range
from several tens to hundreds of MeV/u at SPIRAL2,
SPES, FRIBS (LNS) and FAIR are required. In addition,
support is needed for new detectors with low detection
threshold detectors with large solid angle coverage and
good isotopic resolution like FAZIA.
4) Nuclear theory is essential to exploit fully the
new opportunities arising from existing and future
facilities and to identify future opportunities, and
should be strengthened at the European level. The
rigorous determination of as yet unquantified properties
of the QCD phase diagram, which are now coming into
experimental reach, requires supercomputers in the
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