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The European Physical Journal A

, Volume 31, Issue 4, pp 804–809 | Cite as

Exploring the details of the QCD phase diagram

  • Ph. de Forcrand
  • O. PhilipsenEmail author
QNP 2006

Abstract.

We summarize our recent results on the phase diagram of QCD with N f = 2 + 1 quark flavors, as a function of temperature T and quark chemical potential μ. Using staggered fermions, lattices with temporal extent N t = 4, and the exact RHMC algorithm, we first determine the critical line in the quark mass plane (m u, d, m s) where the finite-temperature transition at μ = 0 is second order. We confirm that the physical point lies on the crossover side of this line. Our data are consistent with a tricritical point at (m u, d, m s) = (0,∼500)MeV. Then, using an imaginary chemical potential, we determine in which direction this second-order line moves as the chemical potential is turned on. Contrary to standard expectations, we find that the region of first-order transitions shrinks in the presence of a chemical potential, which is inconsistent with the presence of a QCD critical point at small chemical potential. The emphasis is put on clarifying the translation of our results from lattice to physical units, and on discussing the apparent contradiction of our findings with earlier lattice studies. Finally, we review related results obtained via simulations at fixed baryon number via the canonical ensemble.

PACS.

12.38.Gc Lattice QCD calculations 12.38.Mh Quark-gluon plasma 

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References

  1. 1.
    E. Laermann, O. Philipsen, Annu. Rev. Nucl. Part. Sci. 53, 163 (2003) [arXiv:hep-ph/0303042]CrossRefADSGoogle Scholar
  2. 2.
    P. Hasenfratz, F. Karsch, I.O. Stamatescu, Phys. Lett. B 133, 221 (1983)CrossRefADSGoogle Scholar
  3. 3.
    P. de Forcrand, O. Philipsen, Nucl. Phys. B 642, 290 (2002) [arXiv:hep-lat/0205016].zbMATHCrossRefADSGoogle Scholar
  4. 4.
    M. D'Elia, M.P. Lombardo, Phys. Rev. D 67, 014505 (2003) [arXiv:hep-lat/0209146].CrossRefADSGoogle Scholar
  5. 5.
    S. Kim, PoS (LAT2005) 166 (2006) [arXiv:hep-lat/0510069].Google Scholar
  6. 6.
    P. de Forcrand, O. Philipsen, Nucl. Phys. B 673, 170 (2003) [arXiv:hep-lat/0307020].CrossRefADSGoogle Scholar
  7. 7.
    M.A. Clark, Nucl. Phys. Proc. Suppl. 140, 835 (2005) [arXiv:hep-lat/0409133].CrossRefADSGoogle Scholar
  8. 8.
    J.B. Kogut, D.K. Sinclair, arXiv:hep-lat/0504003.Google Scholar
  9. 9.
    M.A. Clark, PoS (LAT2005) 115 (2006) [arXiv:hep-lat/0510004].Google Scholar
  10. 10.
    P. de Forcrand, O. Philipsen, arXiv:hep-lat/0607017.Google Scholar
  11. 11.
    D.K. Sinclair, J.B. Kogut, arXiv:hep-lat/0609041.Google Scholar
  12. 12.
    Z. Fodor, S.D. Katz, JHEP 0404, 050 (2004) [arXiv:hep-lat/0402006].CrossRefADSGoogle Scholar
  13. 13.
    Y. Aoki, G. Endrodi, Z. Fodor, S.D. Katz, K.K. Szabo, Nature 443, 675 (2006).CrossRefADSGoogle Scholar
  14. 14.
    Z. Szep, PoS (JHW2005) 017 (2006) [arXiv:hep-ph/0512241].Google Scholar
  15. 15.
    M. Golterman, Y. Shamir, B. Svetitsky, Phys. Rev. D 74, 071501 (2006) [arXiv:hep-lat/0602026].CrossRefADSGoogle Scholar
  16. 16.
    R.V. Gavai, S. Gupta, Phys. Rev. D 71, 114014 (2005) [arXiv:hep-lat/0412035].CrossRefADSGoogle Scholar
  17. 17.
    J.B. Kogut, D.K. Sinclair, Phys. Rev. D 73, 074512 (2006) [arXiv:hep-lat/0603021]CrossRefADSGoogle Scholar
  18. 18.
    F. Karsch, Nucl. Phys. Proc. Suppl. 129, 614 (2004) [arXiv:hep-lat/0309116].CrossRefADSGoogle Scholar
  19. 19.
    P. de Forcrand, S. Kratochvila, PoS (LAT2005) 167 (2006) [arXiv:hep-lat/0509143]Google Scholar

Copyright information

© Società Italiana di Fisica and Springer-Verlag 2007

Authors and Affiliations

  1. 1.Institut für Theoretische PhysikETH ZürichZürichSwitzerland
  2. 2.Physics Department, TH UnitCERNGeneva 23Switzerland
  3. 3.Institut für Theoretische PhysikWestfälische Wilhelms-Universität MünsterGermany

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