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Sep 23, 2013
09/13

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Z. Fodor

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Recent developments on the four dimensional (4d) lattice studies of the finite temperature electroweak phase transition (EWPT) are summarized. The phase diagram is given in the continuum limit. The finite temperature SU(2)-Higgs phase transition is of first order for Higgs-boson masses m_H

Source: http://arxiv.org/abs/hep-lat/9909162v1

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Sep 22, 2013
09/13

by
Z. FODOR

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The finite temperature electroweak phase transition is studied on the lattice. The results of the simulations obtained by the 3-dimensional effective theories and the 4-dimensional SU(2)-Higgs model are reviewed.

Source: http://arxiv.org/abs/hep-lat/9503014v1

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Sep 21, 2013
09/13

by
Z. Fodor

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Recent results on QCD thermodynamics are presented. The nature of the T>0 transition is determined, which turns out to be an analytic cross-over. The absolute scale for this transition is calculated. The results were obtained by using a Symanzik improved gauge and stout-link improved fermionic action. In order to approach the continuum limit four different sets of lattice spacings were used with temporal extensions N_t=4, 6, 8 and 10 (they correspond to lattice spacings a \sim 0.3, 0.2, 0.15...

Source: http://arxiv.org/abs/0712.2930v1

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Sep 19, 2013
09/13

by
Z. Fodor

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Recent lattice results on QCD at finite temperatures and densities are reviewed. Two new and independent techniques give compatible results for physical quantities. The phase line separating the hadronic and quark-gluon plasma phases, the critical endpoint and the equation of state are discussed.

Source: http://arxiv.org/abs/hep-lat/0209101v1

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Sep 17, 2013
09/13

by
Z. Fodor

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Recent results on QCD thermodynamics are presented. The nature of the T>0 transition is determined, which turns out to be an analytic cross-over. The absolute scale for this transition is calculated. The temperature dependent static potential is given. The results were obtained by using a Symanzik improved gauge and stout-link improved fermionic action. In order to approach the continuum limit four different sets of lattice spacings were used with temporal extensions N_t=4, 6, 8 and 10 (they...

Source: http://arxiv.org/abs/0711.0336v1

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Sep 19, 2013
09/13

by
Z. Fodor

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The origin of highest energy cosmic rays (UHECR) is yet unknown. In order to understand their propagation we determine the probability that an ultrahigh energy (above 5\cdot 10^{19} eV) proton created at a distance r with energy E arrives at earth above a threshold E_c. The clustering of ultrahigh energy cosmic rays suggests that they might be emitted by compact sources. A statistical analysis on the source density based on the multiplicities is presented. The ultrahigh energy cosmic ray...

Source: http://arxiv.org/abs/hep-ph/0302036v1

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Sep 22, 2013
09/13

by
Z. FODOR

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The electroweak phase transition is studied at finite temperature. The effective action is given to higher orders, including wave function correction factors and the full $g^4,\lambda^2$ effective potential. An upper bound for the Higgs mass $m_{H} \approx 70\ GeV$ is concluded for the reliability of the perturbative approach. A gauge invariant treatment of the phase transition is presented.

Source: http://arxiv.org/abs/hep-ph/9503325v1

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Sep 20, 2013
09/13

by
Z. Fodor

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We determine the probability that an ultrahigh energy (above 5\cdot 10^{19} eV) proton created at a distance r with energy E arrives at earth above a threshold E_c. The clustering of ultrahigh energy cosmic rays suggests that they might be emitted by compact sources. We present a statistical analysis on the source density based on the multiplicities. The ultrahigh energy cosmic ray spectrum is consistent with the decay of GUT scale particles. By using a maximum likelihood analysis we determine...

Source: http://arxiv.org/abs/hep-ph/0204296v1

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Sep 21, 2013
09/13

by
Z. Fodor; A. Hebecker

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The standard model effective potential is calculated at finite temperature to order $g^4,\la^2$ and a complete zero temperature renormalization is performed. In comparison with lower order calculations the strength of the first order phase transition has increased dramatically. This effect can be traced back to infrared contributions from typical non-Abelian diagrams and to the infrared behaviour of the scalar sector close to the critical temperature. Several quantities, e.g. surface tension,...

Source: http://arxiv.org/abs/hep-ph/9403219v1

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Sep 20, 2013
09/13

by
F. Csikor; Z. Fodor

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We calculate the ${\cal O}(g^2,\lambda)$ corrections to the coupling anisotropies of the SU(2)-Higgs model on lattices with asymmetric lattice spacings. These corrections are obtained by a one-loop calculation requiring the rotational invariance of the gauge- and Higgs-boson propagators in the continuum limit.

Source: http://arxiv.org/abs/hep-lat/9603023v1

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Sep 19, 2013
09/13

by
W. Buchmüller; Z. Fodor

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We investigate the possibility to search for supersymmetry in the scattering of protons and Compton back-scattered laser light. We evaluate the cross sections for inelastic and elastic production of wino pairs for different electron-proton c.m.s. energies. For $\sqrt{s}=1\ TeV$ the cross section exceeds $1\ fb$ for $m_w

Source: http://arxiv.org/abs/hep-ph/9307206v1

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Sep 21, 2013
09/13

by
W. Buchmuller; Z. Fodor

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The infrared behaviour of the standard model at finite temperature is determined by the confining phase of the SU(2)-Higgs model in three dimensions. Due to the Landau singularity of the three-dimensional gauge theory the perturbative treatment of the electroweak phase transition breaks down for Higgs masses above a critical mass $m_H^c$. Based on a renormalization group improved effective potential we find $m_H^c\sim$ 70 GeV. The scalar self-coupling has a Landau-type singularity also in the...

Source: http://arxiv.org/abs/hep-ph/9403388v1

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Sep 21, 2013
09/13

by
F. Csikor; Z. Fodor

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The new contributions to the electron (muon) anomalous magnetic moment arising in mirror fermion theories have been calculated. Imposing the experimental constraint lowers the current upper bound on the ordinary - mirror lepton mixing angles by a factor of 50 making predictions for mirror lepton production at HERA undetectably small. A way out is to allow for different mixing angles of the L and R field components. Choosing very small right mixing angles compatibility with the anomalous...

Source: http://arxiv.org/abs/hep-ph/9205222v1

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Sep 20, 2013
09/13

by
F. Csikor; Z. Fodor

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We discuss the perturbative running of alpha_s in a model independent way. Our analysis contains data on the hadronic tau decay and hadronic cross sections in e+e- annihilation between 5 GeV and M_Z. We determine the color coefficients and the perturbative beta-function of the strong interaction. The results are in agreement with QCD and rule out the QCD+light gluino scenarios on the 70.8 - 93.0% CL. We combine our method with that of the multi-jet analysis at LEP. The combined result rules out...

Source: http://arxiv.org/abs/hep-ph/9611320v3

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Sep 21, 2013
09/13

by
Z. Fodor; S. D. Katz

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Due to the sign problem, it is exponentially difficult to study QCD on the lattice at finite chemical potential. We propose a method --an overlap improving multi-parameter reweighting technique-- to alleviate this problem. We apply this method and give the phase diagram of four-flavor QCD obtained on lattices 4^4 and 4\cdot6^3. Our results are based on {\cal{O}}(10^3-10^4) configurations.

Source: http://arxiv.org/abs/hep-lat/0104001v2

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Sep 22, 2013
09/13

by
Z. Fodor; S. D. Katz

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Recent results on the QCD phase diagram are reviewed. We begin with a detailed introduction of lattice techniques. Then results at vanishing chemical potential are presented. The order of the phase transition, the transition temperature and the equation of state are discussed. At non-vanishing chemical potential we study the mu-T phase line, the critical point as well as the equation of state.

Source: http://arxiv.org/abs/0908.3341v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz

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We analyze the spectrum of the ultrahigh energy (above \approx 10^{9} GeV) cosmic rays. With a maximum likelihood analysis we show that the observed spectrum is consistent with the decay of extragalactic GUT scale particles. The predicted mass for these superheavy particles is m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.

Source: http://arxiv.org/abs/hep-ph/0105348v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz

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The clustering of ultrahigh energy (>10^{20} eV) cosmic rays (UHECR) suggests that they might be emitted by compact sources. Statistical analysis (Dubovsky et al., 2000) estimated the source density. We extend their analysis to give also the confidence intervals (CI) for the source density using a.) no assumptions on the relationship between clustered and unclustered events; b.) nontrivial distributions for the source luminosities and energies; c.) the energy dependence of the propagation....

Source: http://arxiv.org/abs/hep-ph/0105347v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz

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The spectrum of ultrahigh energy (above \approx 10^{9} GeV) cosmic rays is consistent with the decay of GUT scale particles. The predicted mass is m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.

Source: http://arxiv.org/abs/hep-ph/0008204v2

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Sep 21, 2013
09/13

by
Z. Fodor; S. D. Katz

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A critical point (E) is expected in QCD on the temperature (T) versus baryonic chemical potential (\mu) plane. Using a recently proposed lattice method for \mu \neq 0 we study dynamical QCD with n_f=2+1 staggered quarks of physical masses on L_t=4 lattices. Our result for the critical point is T_E=162 \pm 2 MeV and \mu_E= 360 \pm 40 MeV. For the critical temperature at \mu=0 we obtained T_c=164 \pm 2 MeV. This work extends our previous study [Z. Fodor and S.D.Katz, JHEP 0203 (2002) 014] by two...

Source: http://arxiv.org/abs/hep-lat/0402006v1

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Sep 17, 2013
09/13

by
Z. Fodor; S. D. Katz

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The clustering of ultra high energy (above 10^20 eV) cosmic rays (UHECR) suggests that they might be emitted by compact sources. Statistical analysis of Dubovsky et al. (Phys. Rev. Lett. 85 (2000) 1154) estimated the source density. We extend their analysis to give also the confidence intervals for the number of sources using a.) no assumptions on the relationship between clustered and unclustered events; b.) nontrivial distributions for the source intensities and energies; c.) the energy...

Source: http://arxiv.org/abs/hep-ph/0007158v2

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Sep 20, 2013
09/13

by
Z. Fodor; S. D. Katz

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We propose a method to study lattice QCD at finite temperature (T) and chemical potential (\mu). We test the method and compare it with the Glasgow method using n_f=4 staggered QCD with imaginary \mu. The critical endpoint (E) of QCD on the Re(\mu)-T plane is located. We use n_f=2+1 dynamical staggered quarks with semi-realistic masses on L_t=4 lattices. Our results are based on {\cal{O}}(10^3-10^4) configurations.

Source: http://arxiv.org/abs/hep-lat/0204029v1

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Sep 22, 2013
09/13

by
Z. Fodor; S. D. Katz

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We propose a method to study lattice QCD at finite temperature and chemical potential. We compare it with direct results and with the Glasgow method by using n_f=4 QCD at Im(\mu)\neq 0. We locate the critical endpoint (E) of QCD on the Re(\mu)-T plane. In this study we use n_f=2+1 dynamical staggered quarks with semi-realistic masses on L_t=4 lattices.

Source: http://arxiv.org/abs/hep-lat/0111064v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz

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We present results on lattice QCD at finite temperature (T) and chemical potential (\mu). We apply the overlap-improving multi-parameter reweighting technique for n_f=4 and 2+1 staggered QCD. We use semi-realistic masses on L_t=4 lattices. The critical endpoint (E) of 2+1 flavour QCD on the \mu-T plane is located. Our results are based on {\cal{O}}(10^3-10^4) configurations.

Source: http://arxiv.org/abs/hep-lat/0401023v1

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Sep 22, 2013
09/13

by
Z. Fodor; S. D. Katz

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We propose a method to study lattice QCD at finite temperature (T) and chemical potential (\mu). We compare the method with direct results and with the Glasgow method by using n_f=4 QCD at Im(\mu)\neq0. We locate the critical endpoint (E) of QCD on the Re(\mu)-T plane. We use n_f=2+1 dynamical staggered quarks with semi-realistic masses on L_t=4 lattices. Our results are based on {\cal{O}}(10^3-10^4) configurations.

Source: http://arxiv.org/abs/nucl-th/0201071v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz

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We propose a method to study lattice QCD at finite T and \mu. We compare it with direct results and with the Glasgow method by using n_f=4 QCD at Im(\mu)\neq 0. We locate the critical endpoint (E) of QCD on the Re(\mu)-T plane. In this study we use n_f=2+1 dynamical staggered quarks with semi-realistic masses on L_t=4 lattices.

Source: http://arxiv.org/abs/hep-lat/0110102v1

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Sep 22, 2013
09/13

by
Z. Fodor; S. D. Katz

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Based on universal arguments it is believed that there is a critical point (E) in QCD on the temperature (T) versus chemical potential (\mu) plane, which is of extreme importance for heavy-ion experiments. Using finite size scaling and a recently proposed lattice method to study QCD at finite \mu we determine the location of E in QCD with n_f=2+1 dynamical staggered quarks with semi-realistic masses on $L_t=4$ lattices. Our result is T_E=160 \pm 3.5 MeV and \mu_E= 725 \pm 35 MeV. For the...

Source: http://arxiv.org/abs/hep-lat/0106002v2

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Sep 21, 2013
09/13

by
Z. Fodor; S. D. Katz; A. Ringwald

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We consider the possibility that a large fraction of the ultrahigh energy cosmic rays are decay products of Z bosons which were produced in the scattering of ultrahigh energy cosmic neutrinos on cosmological relic neutrinos. We compare the observed ultrahigh energy cosmic ray spectrum with the one predicted in the above Z-burst scenario and determine the required mass of the heaviest relic neutrino as well as the necessary ultrahigh energy cosmic neutrino flux via a maximum likelihood analysis....

Source: http://arxiv.org/abs/hep-ph/0203198v1

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Sep 21, 2013
09/13

by
W. Buchmuller; Z. Fodor; A. Hebecker

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We evaluate the gauge invariant effective potential for the composite field $\sigma=2\Phi^{\dagger}\Phi$ in the SU(2)-Higgs model at finite temperature. Symmetric and broken phases correspond to the domains $\sigma\leq T^2/3$ and $\sigma > T^2/3$, respectively. The effective potential increases very steeply at small values of $\sigma$. Predictions for several observables, derived from the ordinary and the gauge invariant effective potential, are compared. Good agreement is found for the...

Source: http://arxiv.org/abs/hep-ph/9403391v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz; A. Ringwald

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We consider the possibility that a large fraction of the ultrahigh energy cosmic rays are decay products of Z bosons which were produced in the scattering of ultrahigh energy cosmic neutrinos on cosmological relic neutrinos. We compare the observed ultrahigh energy cosmic ray spectrum with the one predicted in the above Z-burst scenario and determine the mass of the heaviest relic neutrino as well as the necessary ultrahigh energy cosmic neutrino flux via a maximum likelihood analysis.

Source: http://arxiv.org/abs/hep-ph/0105336v1

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Sep 19, 2013
09/13

by
F. Csikor; Z. Fodor; J. Heitger

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We present a calculation of the O(g^2,\lambda) perturbative corrections to the coupling anisotropies of the SU(2)-Higgs model on lattices with asymmetric lattice spacings. These corrections are obtained by a one-loop calculation requiring the rotational invariance of the gauge and Higgs boson propagators in the continuum limit. The coupling anisotropies are also determined from numerical simulations of the model on appropriate lattices. The one-loop perturbation theory and the simulation...

Source: http://arxiv.org/abs/hep-lat/9804026v2

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz; G. Papp

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We study the feasibility of a PC-based parallel computer for medium to large scale lattice QCD simulations. The E\"otv\"os Univ., Inst. Theor. Phys. cluster consists of 137 Intel P4-1.7GHz nodes with 512 MB RDRAM. The 32-bit, single precision sustained performance for dynamical QCD without communication is 1510 Mflops/node with Wilson and 970 Mflops/node with staggered fermions. This gives a total performance of 208 Gflops for Wilson and 133 Gflops for staggered QCD, respectively (for...

Source: http://arxiv.org/abs/hep-lat/0202030v3

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz; A. Ringwald

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The origin of highest energy cosmic rays is yet unknown. An appealing possibility is the so-called Z-burst scenario, in which a large fraction of these cosmic rays are decay products of Z bosons produced in the scattering of ultrahigh energy neutrinos on cosmological relic neutrinos. The comparison between the observed and predicted spectra constrains the mass of the heaviest neutrino. The required neutrino mass is fairly robust against variations of the presently unknown quantities, such as...

Source: http://arxiv.org/abs/hep-ph/0210123v2

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Sep 18, 2013
09/13

by
F. Csikor; Z. Fodor; J. Heitger

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We give the nonperturbative phase diagram of the four-dimensional hot electroweak phase transition. A systematic extrapolation $a \to 0$ is done. Our results show that the finite temperature SU(2)-Higgs phase transition is of first order for Higgs-boson masses $m_H

Source: http://arxiv.org/abs/hep-ph/9809293v2

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Sep 22, 2013
09/13

by
F. Csikor; Z. Fodor; J. Heitger

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In this letter we present the results of our numerical simulations for the finite temperature electroweak phase transition using the SU(2)-Higgs model on four-dimensional lattices at $m_H \approx 80$ GeV. The temporal extension $L_t=2$ is used for asymmetric lattice spacings with an asymmetry parameter $a_s/a_t \approx 4$. The measured thermodynamical quantities (interface tension, jump of the order parameter and latent heat) suggest that the phase transition is of very weakly first order.

Source: http://arxiv.org/abs/hep-lat/9807021v2

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Sep 19, 2013
09/13

by
Z. Fodor; S. D. Katz; G. Papp

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A PC-based parallel computer for medium/large scale lattice QCD simulations is suggested. The Eotvos Univ., Inst. Theor. Phys. cluster consists of 137 Intel P4-1.7GHz nodes. Gigabit Ethernet cards are used for nearest neighbor communication in a two-dimensional mesh. The sustained performance for dynamical staggered(wilson) quarks on large lattices is around 70(110) GFlops. The exceptional price/performance ratio is below $1/Mflop.

Source: http://arxiv.org/abs/hep-lat/0209115v1

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Sep 18, 2013
09/13

by
Z. Fodor; S. D. Katz; A. Ringwald

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Ultrahigh energy neutrinos (UHE\nu) scatter on relic neutrinos (R\nu) producing Z bosons, which can decay hadronically producing protons (Z-burst). We compare the predicted proton spectrum with the observed ultrahigh energy cosmic ray (UHECR) spectrum and determine the mass of the heaviest R\nu via a maximum likelihood analysis. Our prediction depends on the origin of the power-like part of the UHECR spectrum: m_\nu=2.75^{+1.28}_{-0.97} eV for Galactic halo and 0.26^{+0.20}_{-0.14} eV for...

Source: http://arxiv.org/abs/hep-ph/0105064v2

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Sep 18, 2013
09/13

by
F. Csikor; Z. Fodor; J. Heitger

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We give the nonperturbative phase diagram of the four-dimensional hot electroweak phase transition. The Monte-Carlo analysis is done on lattices with different lattice spacings ($a$). A systematic extrapolation $a \to 0$ is done. Our results show that the finite temperature SU(2)-Higgs phase transition is of first order for Higgs-boson masses $m_H

Source: http://arxiv.org/abs/hep-ph/9809291v1

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Sep 18, 2013
09/13

by
F. Csikor; Z. Fodor; P. Kovács

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Radiative symmetry breaking is a well known phenomenon in perturbation theory. We study the problem in a non-perturbative framework, i.e. lattice simulations. The example of the bosonic sector of the SU(2)-Higgs model is considered. We determine the minimal scalar mass which turns out to be higher than the mass value given by 1-loop continuum perturbation theory.

Source: http://arxiv.org/abs/hep-lat/0210038v1

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Sep 21, 2013
09/13

by
W. Buchmuller; Z. Fodor; A. Hebecker

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We discuss several general aspects of the free energy of the standard model at high temperatures. In particular the Clausius-Clapeyron equation is shown to yield a relation between the latent heat and the jump in the order parameter. The free energy is calculated as function of temperature in resummed perturbation theory to two-loop order. A new resummation procedure is proposed in which the symmetric phase and the Higgs phase are treated differently. A quantitative description of the phase...

Source: http://arxiv.org/abs/hep-ph/9502321v1

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Sep 23, 2013
09/13

by
G. Endrodi; Z. Fodor; S. D. Katz; K. K. Szabo

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We present results for the equation of state upto previously unreachable, high temperatures. Since the temperature range is quite large, a comparison with perturbation theory can be done directly.

Source: http://arxiv.org/abs/0710.4197v1

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Jul 20, 2013
07/13

by
F. Csikor; Z. Fodor; P. Hegedüs; A. Piróth

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We present a one-loop calculation of the static potential in the SU(2)-Higgs model. The connection to the coupling constant definition used in lattice simulations is clarified. The consequences in comparing lattice simulations and perturbative results for finite temperature applications are explored.

Source: http://arxiv.org/abs/hep-ph/9906260v1

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Sep 21, 2013
09/13

by
Z. Fodor; S. D. Katz; K. K. Szabo

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We present first, exploratory results of a hybrid Monte-Carlo algorithm for dynamical, n_f=2, four-dimensional QCD with overlap fermions. As expected, the computational requirements are typically two orders of magnitude larger for the dynamical overlap formalism than for the more conventional (Wilson or staggered) formulations.

Source: http://arxiv.org/abs/hep-lat/0311010v1

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Sep 18, 2013
09/13

by
Z. Fodor; K. K. Szabo; B. C. Toth

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A spectroscopic method for staggered fermions based on thermodynamical considerations is proposed. The canonical partition functions corresponding to the different quark number sectors are expressed in the low temperature limit as polynomials of the eigenvalues of the reduced fermion matrix. Taking the zero temperature limit yields the masses of the lowest states. The method is successfully applied to the Goldstone pion and both dynamical and quenched results are presented showing good...

Source: http://arxiv.org/abs/0704.2382v2

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Sep 19, 2013
09/13

by
F. Csikor; Z. Fodor; J. Hein; J. Heitger

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In our nonperturbative lattice investigation we study the interface tension of the finite-temperature electroweak phase transition. In this analysis the Higgs mass has been chosen to be about $35$ GeV. At the transition point of a finite volume system, tunnelling between the symmetric and the Higgs phase takes place. This phenomenon leads to a splitting of the ground state, which can be used to determine the interface tension. The result obtained this way agrees with the result of the...

Source: http://arxiv.org/abs/hep-lat/9506029v1

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Sep 18, 2013
09/13

by
Y. Aoki; F. Csikor; Z. Fodor; A. Ukawa

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We report results of a study of the end point of the electroweak phase transition of the SU(2) gauge-Higgs model defined on a four-dimensional isotropic lattice with N_t=2. Finite-size scaling study of Lee-Yang zeros yields lambda_c=0.00116(16) for the end point. Combined with a zero-temperature measurement of Higgs and W boson masses, this leads to M_{H,c}=68.2+-6.6 GeV for the critical Higgs boson mass. An independent analysis of Binder cumulant gives a consistent value lambda_c=0.00102(3)...

Source: http://arxiv.org/abs/hep-lat/9809122v1

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Sep 18, 2013
09/13

by
G. Endrodi; Z. Fodor; S. D. Katz; K. K. Szabo

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We determine the phase diagram of QCD on the \mu-T plane for small to moderate chemical potentials. Two transition lines are defined with two quantities, the chiral condensate and the strange quark number susceptibility. The calculations are carried out on N_t =6,8 and 10 lattices generated with a Symanzik improved gauge and stout-link improved 2+1 flavor staggered fermion action using physical quark masses. After carrying out the continuum extrapolation we find that both quantities result in a...

Source: http://arxiv.org/abs/1102.1356v1

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Sep 23, 2013
09/13

by
Y. Aoki; Z. Fodor; S. D. Katz; K. K. Szabo

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The equation of state of QCD at vanishing chemical potential as a function of temperature is determined for two sets of lattice spacings. Coarser lattices with temporal extension of N_t=4 and finer lattices of N_t=6 are used. Symanzik improved gauge and stout-link improved staggered fermionic actions are applied. The results are given for physical quark masses both for the light quarks and for the strange quark. Pressure, energy density, entropy density, quark number susceptibilities and the...

Source: http://arxiv.org/abs/hep-lat/0510084v2

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68

Jul 20, 2013
07/13

by
Y. Aoki; Z. Fodor; S. D. Katz; K. K. Szabo

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The transition temperature ($T_c$) of QCD is determined by Symanzik improved gauge and stout-link improved staggered fermionic lattice simulations. We use physical masses both for the light quarks ($m_{ud}$) and for the strange quark ($m_s$). Four sets of lattice spacings ($N_t$=4,6,8 and 10) were used to carry out a continuum extrapolation. It turned out that only $N_t$=6,8 and 10 can be used for a controlled extrapolation, $N_t$=4 is out of the scaling region. Since the QCD transition is a...

Source: http://arxiv.org/abs/hep-lat/0609068v2

41
41

Sep 22, 2013
09/13

by
Z. Fodor; S. D. Katz; K. K. Szabo

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We present results of a hybrid Monte-Carlo algorithm for dynamical, $n_f=2$, four-dimensional QCD with overlap fermions. The fermionic force requires careful treatment, when changing topological sectors. The pion mass dependence of the topological susceptibility is studied on $6^4$ and $12\cdot 6^3$ lattices. The results are transformed into physical units.

Source: http://arxiv.org/abs/hep-lat/0409070v1