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J. Rank

Publications and source records attributed to J. Rank.

7 recordsLinked to original sources
arXiv1997

The Gluon Propagator at High Temperature: Screening, Improvement and Non-Zero Momenta

We study the gluon propagator and the singlet potential in Landau gauge in the deconfined phase of SU(2) lattice gauge theory, using both the standard Wilson action and a tree-level Symanzik improved action. From the long-distance behavior of correlation functions of temporal and spatial components of the gauge fields we extract electric (m_e) and magnetic (m_m) screening masses. For the magnetic mass we find m_m(T) = 0.456(6) g^2(T) T. The electric mass can be described by a next-to leading order ansatz, obtained from one loop resummed perturbation theory. However, the best description is given by m_e(T) = \sqrt{1.70(2)} g(T) T. The electric screening mass thus is different from its lowest order perturbative prediction even for temperatures as high as T \sim 10^4 T_c.

hep-lat↗
arXiv1997

Screening Lengths in SU(2) Gauge Theory at Finite Temperature

We discuss the calculation of electric and magnetic screening masses in SU(2) gauge theory. The temperature dependence of these masses obtained from the long-distance behaviour of spatial correlation functions has been analyzed for temperatures up to 10000 T_c.

hep-lat↗
arXiv1996

The Non-Perturbative ${\cal O}(g^6)$ Contribution to the Free Energy of Hot SU(N) Gauge Theory

The non-perturbative input necessary for the determination of the ${\cal O}(g^6)$ part of the weak coupling expansion of the free energy density for SU(2) and SU(3) gauge theories is estimated. Although the perturbative information completing the contribution to this order is missing, we give arguments that the magnetic fluctuations are dominated by screened elementary magnetic gluons.

hep-lat↗
arXiv1996

Critical Higgs Mass and Temperature Dependence of Gauge Boson Masses in the SU(2) Gauge-Higgs Model

We study the effective 3-D SU(2) Gauge-Higgs model at finite temperature for Higgs-masses in the range from $60$ GeV up to $100$ GeV. The first order electroweak phase transition weakens with increasing Higgs-mass and terminates at a critical end-point. For Higgs-mass values larger than about $m_{H,c}=75.4(6)$ GeV the thermodynamic signature of the transition is described by a crossover. Close to this Higgs-mass value we investigate the vector boson propagator in Landau gauge. The calculated W-boson screening masses are compared with predictions based on gap equations.

hep-lat↗
arXiv1996

The ${\cal O}(g^6)$ coefficient in the thermodynamic potential of hot SU(N) Gauge Theories and MQCD

The non-perturbative input necessary for the determination of the ${\cal O}(g^6)$ part of the weak coupling expansion of the free energy density for SU(2) and SU(3) gauge theories is estimated. Although the perturbative information completing the contribution to this order is missing, we give arguments that the magnetic fluctuations are dominated by screened elementary magnetic gluons.

hep-lat↗
arXiv1996

Gauge Boson Masses in the 3-d, SU(2) Gauge-Higgs Model

We study gauge boson propagators in the symmetric and symmetry broken phases of the 3-d, $SU(2)$ gauge-Higgs model. Correlation functions for the gauge fields are calculated in Landau gauge. They are found to decay exponentially at large distances leading to a non-vanishing mass for the gauge bosons. We find that the W-boson screening mass drops in the symmetry broken phase when approaching the critical temperature. In the symmetric phase the screening mass stays small and is independent of the scalar--gauge coupling (the hopping parameter). Numerical results coincide with corresponding calculations performed for the pure gauge theory. We find $m_w = 0.35(1)g^2T $ in this phase which is consistent with analytic calculations based on gap equations. This is, however, significantly smaller than masses extracted from gauge invariant vector boson correlation functions. As internal consistency check we also have calculated correlation functions for gauge invariant operators leading to scalar and vector boson masses. Finite lattice size effects have been systematically analyzed on lattices of size $L^2\times L_z$ with $L=4-24$ and $L_z = 16 - 128$.

hep-lat↗