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arXiv · 0804.4863

Glueballs and the superfluid phase of Two-Color QCD

Maria Paola Lombardo·Maria Luigia Paciello·Silvano Petrarca·Bruno Taglienti
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Abstract

We present the first results on scalar glueballs in cold, dense matter using lattice simulations of two color QCD. The simulations are carried out on a $6^3 \times 12$ lattice and use a standard hybrid molecular dynamics algorithm for staggered fermions for two values of quark mass. The glueball correlators are evaluated via a multi-step smearing procedure. The amplitude of the glueball correlator peaks in correspondence with the zero temperature chiral transition, $μ_c = m_π/2$, and the propagators change in a significant way in the superfluid phase, while the Polyakov loop is mearly insensitive to the transition. Standard analysis suggest that lowest mass in the $0^{++}$ gluonic channel decreases in the superfluid phase, but these observations need to be confirmed on larger and more elongated lattices These results indicate that a nonzero density induces nontrivial modifications of the gluonic medium.

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Maria Paola Lombardo, Maria Luigia Paciello, Silvano Petrarca, Bruno Taglienti. 2008-08-22. Glueballs and the superfluid phase of Two-Color QCD. https://doi.org/10.1140/epjc%2Fs10052-008-0718-z

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