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FEATURES

At the early plans the only dedicated heavy iondetector was ALICE, but as the first resultsstarted to arise, also ALAS and CMS startedto invest increasingly more effort into heavyion research. Tis change o interest has two aspects. Con-trary to early expectations o very high hadron multiplicitythe collective flow became more dominant and a larger parto the available energy (o 208 2.76 eV = 574 eV) isinvested into the collective flow, which developed in the

QGP. Te number o produced final particles is not as highas expected. Tis made the ALAS and CMS detectorsully adequate or heavy ion research, and these detectorsprovided even a more extended rapidity acceptance, com-plementing the possibilities o ALICE detector well.

Te second aspect was recognized afer the very heavy-ion first results [1], where the heavy-ion studies providednew and important insight into the eatures o QGP. QGPturned out a strongly coupled liquid, with small viscosity,especially at the threshold o the quark/hadron phasetransition. Te small viscosity, the related fluctuations,and the flow properties arising rom these fluctuationsenable us to gain insight into the properties o the mattero the early universe, and also the fluctuations observed

in the early universe. Tese new results raised more inter-est in the ALAS and CMS collaborations also and theirprogress in the heavy ion research activity is becomingmore important. In recent months the CERN Courierhas more and more news about new heavy-ion results.

The Quark-Gluon Plasma,a nearly perfect fluidl L. Cifarelli1, L.P. Csernai2and H. Stcker3-DOI: 10.1051/epn/2012206

l 1Dipartimento di Fisica,Universita di Bologna,40126 Bologna,Italy;

l 2Department of Physics and Technology,University of Bergen,5007 Bergen,Norway;

l 3GSI Helmholtzzentrum fr Schwerionenforschung,64291 Darmstadt,Germany

We are living in interesting times, where the Worlds largest accelerator, the

Large Hadron Collider, has its most dominant successes in Nuclear Physics:

collective matter properties of the Quark-Gluon Plasma (QGP) are studied

at a detail which is not even possible for conventional, macro scale materials.

view of theexpanding androtating Quark-GluonPlasma from a fluid

dynamical calculation(discussed in: L.P.Csernai, V.K. Magas,H. Stcker, and D.D.Strottman, Phys. Rev.C84, 02914 (2011).)

Article available athttp://www.europhysicsnews.orgorhttp://dx.doi.org/10.1051/epn/2012206

http://www.europhysicsnews.org/http://dx.doi.org/10.1051/epn/2012206http://dx.doi.org/10.1051/epn/2012206http://www.europhysicsnews.org/

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References

[1] K. Aamodt et al., (ALICE Collaboration),Phys. Rev. Lett. 105,

252302 (2010)

[2] K. Aamodt et al., (ALICE Collaboration) arXiv:1105.3865v1

[nucl-ex], and CERN Courier, October 2011, p. 6

[3] P.K. Kovtun, D.T. Son and A.O. Starinets,Phys. Rev. Lett. 94,

111601 (2005)

[4] L.P. Csernai, J.I. Kapusta, L.D. McLerran,Phys. Rev. Lett. 97,

152303 (2006)

[5] STAR Collaboration,Science 328,58 (2010) and Nature 473,

353 (2011)[6] J. Steinheimer, M. Mitrovski, T. Schuster, H. Petersen,

M. Bleicher and H. Stcker,Phys. Lett. B 676, 126 (2009),

arXiv:0811.4077 [hep-ph].

and according to present expectations it is around the lowRHIC and the SPS energies. Te present CERN studiescould be well complemented by studying a system wherethe QGP is just created and critical fluctuations in densehadronic o baryonic matter can be studied. Apart rom thedrop o collective directed flow due to the rapid sofeningo the matter at the critical point, there are many otherobservables, which open new ways o studies. Te revolu-tionary fluctuation studies have an effect on the studies atthe critical point also, with many new results coming romthe RHIC Beam Energy Scan program. Here the criticalfluctuations are being in the ocus o present and utureresearch. Tese show up in the anomalous multiplicity andmass distribution o the produced matter as relics o QGP.Tese ragments, hypernuclei, anti-baryons, anti-nuclei,antihypernuclei and even anti matter atoms like anti-4He.

FAIR and NICACritical fluctuations, critical dynamics and the relicso QGP can be best generated at the phase transitionthreshold. Te planned Facility or Antiproton and IonResearch (FAIR) in Darmstadt and the Nuclotron basedIon Collider Acility (NICA) in Dubna are addressing

these questions. According to theoretical expectationsthe production o these exotic nuclear ragments opensin this energy range [5].Figure 5 shows theoretical predictions or anti-particlecluster production at mid-rapidity (|y|