The Binder cumulant in O(N)-models

20 May 2014, 16:30
spectrum (darmstadtium)



Board: B-20
Poster QCD Phase Diagram Poster session


Mr Paul Springer (Technische Universität München)


The phase structure of QCD is currently a much discussed topic in particle physics. In the context of this discussion we need precise knowledge about the nature of the chiral phase transition. A powerful tool to investigate it are lattice simulations. They are, however, still restricted to relatively large quark masses, far from the chiral limit, and to small volumes, which could affect the critical behavior. These two facts complicate the scaling analysis of lattice QCD results. In the chiral limit, a continuous phase transition is expected in two-flavor QCD. Since continuous phase transitions are controlled by the long range fluctuations, only the dimensionality and symmetries dictate the universal behavior near the critical point. Therefore, more simple systems from the same universality class can be investigated in order to describe scaling behavior which is expected at the chiral phase transition in lattice QCD. Because the long range fluctuations play such a prominent role at continuous phase transitions, it is self-evident that it is useful to investigate precisely the behavior of higher-order critical fluctuations close to the transition point. For this purpose the so-called Binder cumulants seem to be very well suited. We analyze the fourth-order Binder cumulant in 3-dimensional O(2)- and O(4)-models in finite volumes using non-perturbative Renormalization Group methods. This approach allows us to gain explicit insight into the behavior of the critical fluctuations and provides a tool which assists in analysis of lattice QCD data.
On behalf of collaboration: None

Primary author

Mr Paul Springer (Technische Universität München)


Dr Bertram Klein (Technische Universität München)

Presentation Materials