The 43GHz SiO maser in the circumstellar envelope of the AGB star R Cassiopeiae

We present multi-epoch, total intensity, high-resolution images of 43GHz, v=1, J=1-0 SiO maser emission toward the Mira variable R Cas. In total we have 23 epochs of data for R Cas at approximate monthly intervals over an optical pulsation phase range from 0.158 to 1.78. These maps show a ring-like distribution of the maser features in a shell, which is assumed to be centred on the star at a radius of 1.6 to 2.3 times the stellar radii. It is clear from these images that the maser emission is significantly extended around the star. At some epochs a faint outer arc can be seen at 2.2 stellar radii. The intensity of the emission waxes and wanes during the stellar phase. Some maser features are seen infalling as well as outflowing. We have made initial comparisons of our data with models by Gray et. al. (2009).Comment: 12 pages, 14 figure

Fiscal Policies, Debt, and International Economic Interdependence

This paper deals with the relation between government spending and real rates of interest as well as with the international transmission of fiscal policies.The dependence of the patterns of consumption in one country on fiscal policiesin the rest of the world are examined. For this purpose a general equilibrium model which is characterized by fully integrated world capital marketsis constructed, economic agents behave rationally, and government policies are constrained to obey the intertemporal solvency requirements. It is shown that the effects of changes 'in countries' net debt or position as well as the effects offiscal policies can be analyzed by reference to a multitude of "transfer problems criteria", which are familiar from the theory of international economic transfers. In the present case the impact of policies depends on the relations among the spending patterns of domestic and foreign private sectors; of domestic and foreign governments, as well as of domestic and foreign saving propensities.The analysis draws a distinction between permanent and transitory policies as well as between current policies and expected future policies.A transitory current fiscal spending, must crowd out the foreign private sector and, thereby,result in a negative transmission. However, a transitory future rise in government spending induces an immediate increase in foreign private sector's consumption and thereby results in a positive current transmission. These responses are reflected in the current account of the balance-of-payments, in changes in the net debtor-creditor positions, and in complex changes in the term structure of interest rates. It is also shown that with full integration of capital markets,fiscal policies may exert different qualitative effects on real rates of interestin different countries since, depending on the structural parameters, the relative prices of non-traded goods, and thereby the price indices, might be negatively correlated between countries.

Realization of SU(N) Kondo effect in strong magnetic field

In this paper we suggest a realization for the SU(N) Kondo effect, using quantum dots at strong magnetic field. We purpose using edge states of the quantum Hall effect as pseudo spin that interact with multiple quantum dots structures. In the suggested realization one can access each pseudo spin separately and hence may perform a set of experiments that were impossible until now. We focus on the realization of SU(2) and SU(3) Kondo and find a conductivity of 3/4 quantum conductance in the SU(3) case.Comment: 5 pages, 2 figures. Including supplementary materia

High Curie temperature Mn 5 Ge 3 thin films produced by non-diffusive reaction

Polycrystalline Mn 5 Ge 3 thin films were produced on SiO 2 using magnetron sputtering and reactive diffusion (RD) or non-diffusive reaction (NDR). In situ X-ray diffraction and atomic force microscopy were used to determine the layer structures, and magnetic force microscopy, superconducting quantum interference device and ferromagnetic resonance were used to determine their magnetic properties. RD-mediated layers exhibit similar magnetic properties as MBE-grown monocrystalline Mn 5 Ge 3 thin films, while NDR-mediated layers show magnetic properties similar to monocrystalline C-doped Mn 5 Ge 3 C x thin films with $0.1 \leq x \leq 0.2.$ NDR appears as a CMOS-compatible efficient method to produce good magnetic quality high-curie temperature Mn 5 Ge 3 thin films

Fiscal Policies and Real Exchange Rates in the World Economy

This paper examines the effects of fiscal policies on the evolution of real rates of interest and real exchange rates in the interdependent world economy. We construct an analytical framework suitable for a detailed examination of the various channels through which these variables are influenced by government spending and by tax policies. The analytical framework employs a general equilibrium approach highlighting the roles played by wealth effects and by temporal and intertemporal substitution effects. The general principle illustrated by the analysis of the dynamic effects of budget deficits is that the consequences of temporary tax policies stretch beyond the period during which the temporary policies are in effect. The counterpart to these dynamic implications is the rise in the economy's external debt induced by the budget deficit the service of which stretches into the indefinite future. By series of examples, allowing for both distortionary and non-distortionary taxes and for various patterns of government spending, it is shown that the quantitative and qualitative effects of fiscal policies on real exchange rates, real interest rates, debt accumulation and the like depend critically on the commodity composition of government spending and its intertemporal allocations on the one hand, and on the details of government debt issue and tax structure, including the timing of taxes and borrowing and the types of taxes used to finance the budget, on the other hand.

Polarization morphology of SiO masers in the circumstellar envelope of the AGB star R Cassiopeiae

Silicon monoxide maser emission has been detected in the circumstellar envelopes of many evolved stars in various vibrationally-excited rotational transitions. It is considered a good tracer of the wind dynamics close to the photosphere of the star. We have investigated the polarization morphology in the circumstellar envelope of an AGB star, R Cas. We mapped the linear and circular polarization of SiO masers in the v=1, J=1-0 transition. The linear polarization is typically a few tens of percent while the circular polarization is a few percent. The fractional polarization tends to be higher for emission of lower total intensity. We found that, in some isolated features the fractional linear polarization appears to exceed 100%. We found the Faraday rotation is not negligible but is ~15 deg., which could produce small scale structure in polarized emission whilst total intensity is smoother and partly resolved out. The polarization angles vary considerably from feature to feature but there is a tendency to favour the directions parallel or perpendicular to the radial direction with respect to the star. In some features, the polarization angle abruptly flips 90 deg. We found that our data are in the regime where the model of Goldreich et al (1973) can be applied and the polarization angle flip is caused when the magnetic field is at close to 55 deg. to the line of sight. The polarization angle configuration is consistent with a radial magnetic field although other configurations are not excluded.Comment: 14 pages, 15 figures. Accepted for publication in MNRA