The Oblique Corrections from Heavy Scalars in Irreducible Representations

The contributions to $S$, $T$, and $U$ from heavy scalars in any irreducible representation of the electroweak gauge group $SU(2)_L\times U(1)_Y$ are obtained. We find that in the case of a heavy scalar doublet there is a slight difference between the $S$ parameter we have obtained and that in previous works.Comment: 6 pages, 2 axodraw figures; minor changes, references update

The two-loop supersymmetric corrections to lepton anomalous magnetic and electric dipole moments

Using the effective Lagrangian method, we analyze the electroweak corrections to the anomalous dipole moments of lepton from some special two-loop topological diagrams which are composed of neutralino (chargino) - slepton (sneutrino) in the minimal supersymmetric extension of the standard model (MSSM). Considering the translational invariance of the inner loop momenta and the electromagnetic gauge invariance, we get all dimension 6 operators and derive their coefficients. After applying equations of motion to the external leptons, the anomalous dipole moments of lepton are obtained. The numerical results imply that there is a parameter space where the two-loop supersymmetric corrections to the muon anomalous dipole moments may be significant.Comment: Revtex, 45 pages, including 8 fig

Non-trivial quantum oscillation geometric phase shift in a trivial band

The accumulation of non-trivial geometric phases in a material's response is often a tell-tale sign of a rich underlying internal structure. Studying quantum oscillations provides one of the ways to determine these geometrical phases, such as Berry's phase, that play a central role in topological quantum materials. We report on magneto-transport measurements in ABA-trilayer graphene, the band structure of which is comprised of a weakly gapped linear Dirac band, nested within a trivial quadratic band. Here we show Shubnikov-de Haas (SdH) oscillations of the quadratic band shifted by a phase that sharply departs from the expected 2$\pi$ Berry's phase. Our analysis reveals that, surprisingly, the anomalous phase shift is non-trivial and is inherited from the non-trivial Berry's phase of the linear Dirac band due to strong filling-enforced constraints between the linear and quadratic band Fermi surfaces. Given that many topological materials contain multiple bands, our work indicates how additional bands, which are thought to obscure the analysis, can actually be exploited to tease out the subtle effects of Berry's phase.Comment: 13 pages, 9 figure

Discovery of new quasi-periodic oscillations in the X-ray transient source V~0332+53

We report the discovery of a new quasi-period oscillation (QPO) at 0.22 Hz, centered on the source spin frequency of the high mass X-ray binary system V~0332+53 when the source was observed during its November 2004/March 2005 outburst by {\em RXTE}. Besides this new QPO, we also detected the known 0.05 Hz QPO. Both the 0.22 and 0.05 Hz QPOs stand out clearly at a mid-flux level of the outburst within January 15--19 2005, and later at an even lower flux level as the width of 0.22 Hz QPO drops. No evolution of the centroid frequency with the flux is seen in either QPO. The rms value below 10 keV is around 4--6% for both QPOs and decreases at higher energies. We discuss our results in the context of current QPO models.Comment: 5 figures, 12 pages. AASTex preprint style. (In 2005, ApJ Let., 629, L33

The Equation of State and Quark Number Susceptibility in Hard-Dense-Loop Approximation

Based on the method proposed in [ H. S. Zong, W. M. Sun, Phys. Rev. \textbf{D 78}, 054001 (2008)], we calculate the equation of state (EOS) of QCD at zero temperature and finite quark chemical potential under the hard-dense-loop (HDL) approximation. A comparison between the EOS under HDL approximation and the cold, perturbative EOS of QCD proposed by Fraga, Pisarski and Schaffner-Bielich is made. It is found that the pressure under HDL approximation is generally smaller than the perturbative result. In addition, we also calculate the quark number susceptibility (QNS) at finite temperature and finite chemical potential under hard-thermal/dense-loop (HTL/HDL) approximation and compare our results with the corresponding ones in the previous literature.Comment: 12 pages, 3 figure

Predicting essential components of signal transduction networks: a dynamic model of guard cell abscisic acid signaling

Plants both lose water and take in carbon dioxide through microscopic stomatal pores, each of which is regulated by a surrounding pair of guard cells. During drought, the plant hormone abscisic acid (ABA) inhibits stomatal opening and promotes stomatal closure, thereby promoting water conservation. Here we synthesize experimental results into a consistent guard cell signal transduction network for ABA-induced stomatal closure, and develop a dynamic model of this process. Our model captures the regulation of more than forty identified network components, and accords well with previous experimental results at both the pathway and whole cell physiological level. Our analysis reveals the novel predictions that the disruption of membrane depolarizability, anion efflux, actin cytoskeleton reorganization, cytosolic pH increase, the phosphatidic acid pathway or of K+ efflux through slowly activating K+ channels at the plasma membrane lead to the strongest reduction in ABA responsiveness. Initial experimental analysis assessing ABA-induced stomatal closure in the presence of cytosolic pH clamp imposed by the weak acid butyrate is consistent with model prediction. Our method can be readily applied to other biological signaling networks to identify key regulatory components in systems where quantitative information is limited.Comment: 17 pages, 8 figure

Universal critical properties of the Eulerian bond-cubic model

We investigate the Eulerian bond-cubic model on the square lattice by means of Monte Carlo simulations, using an efficient cluster algorithm and a finite-size scaling analysis. The critical points and four critical exponents of the model are determined for several values of $n$. Two of the exponents are fractal dimensions, which are obtained numerically for the first time. Our results are consistent with the Coulomb gas predictions for the critical O($n$) branch for $n < 2$ and the results obtained by previous transfer matrix calculations. For $n=2$, we find that the thermal exponent, the magnetic exponent and the fractal dimension of the largest critical Eulerian bond component are different from those of the critical O(2) loop model. These results confirm that the cubic anisotropy is marginal at $n=2$ but irrelevant for $n<2$

Off-shell effects in dilepton production from hot interacting mesons

The production of dielectrons in reactions involving a_1 mesons and pions is studied. We compare results obtained with different phenomenological Lagrangians that have been used in connection with hadronic matter and finite nuclei. We insist on the necessity for those interactions to satisfy known empirical properties of the strong interaction. Large off-shell effects in dielectron production are found and some consequences for the interpretation of heavy ion data are outlined. We also compare with results obtained using experimentally-extracted spectral functions.Comment: 14 pages, LaTeX2e, 2 figure