The Galactic distribution of magnetic fields in molecular clouds and HII regions

{Magnetic fields exist on all scales in our Galaxy. There is a controversy about whether the magnetic fields in molecular clouds are preserved from the permeated magnetic fields in the interstellar medium (ISM) during cloud formation. We investigate this controversy using available data in the light of the newly revealed magnetic field structure of the Galactic disk obtained from pulsar rotation measures (RMs).} % {We collected measurements of the magnetic fields in molecular clouds, including Zeeman splitting data of OH masers in clouds and OH or HI absorption or emission lines of clouds themselves.} % {The Zeeman data show structures in the sign distribution of the line-of-sight component of the magnetic field. Compared to the large-scale Galactic magnetic fields derived from pulsar RMs, the sign distribution of the Zeeman data shows similar large-scale field reversals. Previous such examinations were flawed in the over-simplified global model used for the large-scale magnetic fields in the Galactic disk.} % {We conclude that the magnetic fields in the clouds may still ``remember'' the directions of magnetic fields in the Galactic ISM to some extent, and could be used as complementary tracers of the large-scale magnetic structure. More Zeeman data of OH masers in widely distributed clouds are required.}Comment: Typo fixed in this new versio

Analytic continuation of single-particle resonance energy and wave function in relativistic mean field theory

Single-particle resonant states in spherical nuclei are studied by an analytic continuation in the coupling constant (ACCC) method within the framework of the self-consistent relativistic mean field (RMF) theory. Taking the neutron resonant state $\nu 1g_{9/2}$ in $^{60}$Ca as an example, we examine the analyticity of the eigenvalue and eigenfunction for the Dirac equation with respect to the coupling constant by means of a \pade approximant of the second kind. The RMF-ACCC approach is then applied to $^{122}$Zr and, for the first time, this approach is employed to investigate both the energies, widths and wave functions for $l\ne 0$ resonant states close to the continuum threshold. Predictions are also compared with corresponding results obtained from the scattering phase shift method.Comment: 19 pages, 9 figure

The Chinese-French SVOM mission for Gamma-Ray Burst studies

We present the Space-based multi-band astronomical Variable Objects Monitor mission (SVOM) decided by the Chinese National Space Agency (CNSA) and the French Space Agency (CNES). The mission which is designed to detect about 80 Gamma-Ray Bursts (GRBs) of all known types per year, will carry a very innovative scientific payload combining a gamma-ray coded mask imagers sensitive in the range 4 keV to 250 keV, a soft X-ray telescope operating between 0.5 to 2 keV, a gamma-ray spectro-photometer sensitive in the range 50 keV to 5 MeV, and an optical telescope able to measure the GRB afterglow emission down to a magnitude limit M$_R=23$ with a 300 s exposure. A particular attention will be also paid to the follow-up in making easy the observation of the SVOM detected GRB by the largest ground based telescopes. Scheduled for a launch in 2013, it will provide fast and reliable GRB positions, will measure the broadband spectral energy distribution and temporal properties of the prompt emission, and will quickly identify the optical afterglows of detected GRBs, including those at very high redshift.Comment: Proceedings of the SF2A conference, Paris, 200

Switching speed distribution of spin-torque-induced magnetic reversal

The switching probability of a single-domain ferromagnet under spin-current excitation is evaluated using the Fokker-Planck equation(FPE). In the case of uniaxial anisotropy, the FPE reduces to an ordinary differential equation in which the lowest eigenvalue $\lambda_1$ determines the slowest switching events. We have calculated $\lambda_1$ by using both analytical and numerical methods. It is found that the previous model based on thermally distributed initial magnetization states \cite{Sun1} can be accurately justified in some useful limiting conditions.Comment: The 10th Joint MMM/Intermag, HA-0

Multi chiral-doublets in one single nucleus

Adiabatic and configuration-fixed constraint triaxial relativistic mean field (RMF) approaches are developed for the first time and a new phenomenon, the existence of multi chiral-doublets (M$\chi$D), i.e., more than one pairs of chiral doublets bands in one single nucleus, is suggested for nuclei in A~100 region, typically for $^{106}$Rh, based on the triaxial deformations together with their corresponding proton and neutron configurations.Comment: 10 pages, 4 figure

Grand Unified Yukawa Matrix Ansatz: The Standard Model Fermion Mass, Quark Mixing and CP Violation Parameters

We propose a new mass matrix ansatz: At the grand unified (GU) scale, the standard model (SM) Yukawa coupling matrix elements are integer powers of the square root of the GU gauge coupling constant \varepsilon \equiv \sqrt{\alpha_{\text{GU}}}, multiplied by order unity random complex numbers. It relates the hierarchy of the SM ermion masses and quark mixings to the gauge coupling constants, greatly reducing the SM parameters, and can give good fitting results of the SM fermion mass, quark mixing and CP violation parameters. This is a neat but very effective ansatz.Comment: 4 pages (two columns), by REVTeX 4, 2 tables, no figures, version for publication in CP