On Topological Susceptibility, Vacuum Energy and Theta Dependence in Gluodynamics

We suggest that the topological susceptibility in gluodynamics can be found in terms of the gluon condensate using renormalizability and heavy fermion representation of the anomaly. Analogous relations can be also obtained for other zero momentum correlation functions involving the topological density operator. Using these relations, we find the theta dependence of the condensates , and of the partition function for small theta and an arbitrary number of colors.Comment: Details of the derivation are clarified, changes in discussions, new references are adde

Efeito da altura do resíduo sobre a produção e a estrutura de sorgo forrageiro.

O cultivo de sorgo forrageiro (Sorghum bicolor (L.) Moench.) tem crescido na região Noroeste do Rio Grande do Sul nos últimos anos. Os produtores rurais estão sendo orientados a manejar o sorgo forrageiro em pastejo rotacionado, respeitando uma altura de entrada dos animais acima de 70 cm e altura de saída (resíduo) em torno de apenas 5 cm.bitstream/item/63868/1/BP31.pd

Universal Behaviour of the Superfluid Fraction and Tc of He-3 in 99.5% Open Aerogel

We have investigated the superfluid transition of He-3 in a 99.5% porosity silica aerogel. This very dilute sample shows behaviour intermediary between bulk He-3 and He-3 confined to the denser aerogels previously studied. We present data on both the superfluid transition temperature and the superfluid density and compare our results with previous measurements. Finally, we show that the suppression of the superfluid transition temperature and suppression of the superfluid density of He-3 in aerogel follow a universal relation for a range of aerogel samples.Comment: 4 pages, 5 figures; 1 new figure, minor change

Efeito da altura do resíduo pós-corte sobre a produção de matéria seca e o perfilhamento em sorgo forrageiro (Sorghum bicolor (L.) Moench cv. AG 2501).

Resumo

Effective Hamiltonian Approach to Hyperon Beta Decay with Final-State Baryon Polarization

Using an effective Hamiltonian approach, we obtain expressions for hyperon beta decay final-state baryon polarization. Terms through second order in the energy release are retained. The resulting approximate expressions are much simpler and more compact than the exact expressions, and they agree closely with them.Comment: 1 Figure Will appear in Phys Rev D 60 Article 117505 (Dec 1, 1999

Propagators in Coulomb gauge from SU(2) lattice gauge theory

A thorough study of 4-dimensional SU(2) Yang-Mills theory in Coulomb gauge is performed using large scale lattice simulations. The (equal-time) transverse gluon propagator, the ghost form factor d(p) and the Coulomb potential V_{coul} (p) ~ d^2(p) f(p)/p^2 are calculated. For large momenta p, the gluon propagator decreases like 1/p^{1+\eta} with \eta =0.5(1). At low momentum, the propagator is weakly momentum dependent. The small momentum behavior of the Coulomb potential is consistent with linear confinement. We find that the inequality \sigma_{coul} \ge \sigma comes close to be saturated. Finally, we provide evidence that the ghost form factor d(p) and f(p) acquire IR singularities, i.e., d(p) \propto 1/\sqrt{p} and f(p) \propto 1/p, respectively. It turns out that the combination g_0^2 d_0(p) of the bare gauge coupling g_0 and the bare ghost form factor d_0(p) is finite and therefore renormalization group invariant.Comment: 10 pages, 7 figure

Pseudoscalar Glueball Mass: QCD vs. Lattice Gauge Theory Prediction

We study whether the pseudoscalar glueball mass in full QCD can differ from the prediction of quenched lattice calculations. Using properties of the correlator of the vacuum topological susceptibility we derive an expression for the upper bound on the QCD glueball mass. We show that the QCD pseudoscalar glueball is lighter than the pure Yang-Mills theory glueball studied in quenched lattice calculations. The mass difference between those two states is of order of $1/N_c$. The value calculated for the $0^{-+}$ QCD glueball mass can not be reconciled with any physical state observed so far in the corresponding channel. The glueball decay constant and its production rate in $J/\psi$ radiative decays are calculated. The production rate is large enough to be studied experimentally.Comment: 18 pages, LaTex fil

Topological susceptibility with the improved Asqtad action

As a test of the chiral properties of the improved Asqtad (staggered fermion) action, we have been measuring the topological susceptibility as a function of quark masses for 2 + 1 dynamical flavors. We report preliminary results, which show reasonable agreement with leading order chiral perturbation theory for lattice spacing less than 0.1 fm. The total topological charge, however, shows strong persistence over Monte Carlo time.Comment: Lattice2002(algor

Group B streptococcal infective endocarditis in a young non-pregnant female with rheumatic heart disease - A Case Report

Group B Streptococcus (GBS) is a rare cause of infective endocarditis in adults associated with a high mortality rate due to the frequent occurrence of local and systemic complications. Here we report a case of infective endocarditis (IE) in a young non-pregnant female with a history of rheumatic heart disease (RHD) who presented with a short history of fever, shortness of breath and constitutional symptoms. GBS was isolated from a single blood culture along with echocardiographic findings of a cardiac vegetation and ophthalmologic findings of a Roth spot. Based on the Modified Duke Criteria, a definitive diagnosis of infective endocarditis was made. She was treated with a prolonged course of intravenous (IV) ceftriaxone, with gentamicin being added to the regimen, following which she made a complete recovery.</p

The 4D SU(3) gauge theory with an imaginary theta term

We study the scaling behavior of the 4D SU(3) lattice gauge theory in the presence of a theta term, by Monte Carlo simulations computing the topological properties at imaginary theta. The numerical results provide a good evidence of scaling in the continuum limit. The imaginary theta dependence of the ground-state energy turns out to be well described by the first few terms of related expansions around theta=0, providing accurate estimates of the first few coefficients, up to O(theta^6).Comment: 12 page