The Asiago Extrasolar Planet Transit Search

RATS is an Italian project devoted to Hot Jupiter search with the transit method. A planet transiting in front of a host star can be mimed by several, and well defined, astrophysical phenomena (Brown, 2003). In order to recognize these false alarms we can utilize a preventive strategy to limit false alarm rates and a spectroscopic follow up to refuse no transit candidates. As preventive strategy it is important to develop an accurate target field selection, with well defined requisites, in order to maximize the solar type star numbers and to minimize the risk of possible astrophysical false alarms.     

Results of the first two years of VLBI observations at the Svetloe Observatory within the framework of international geodynamical programs

We present the results of processing the VLBI observations performed at the Svetloe Observatory of the Institute of Applied Astronomy (IAA), Russian Academy of Sciences, in the period 2003–2005 within the framework of geodynamical programs of the International VLBI Service (IVS) for geodesy and astrometry. We analyzed the observations at the Svetloe Observatory, together with the observations at other stations of the global IVS network, at the IAA using a modified OCCAM package. The package uses new reduction models that decrease the systematic errors of the results. The motion of the stations, primarily of the Svetloe Observatory, is investigated to study the global geotectonic processes. Highly accurate estimates of the coordinate and baseline length variations have been obtained for the first time in Russia from observations at a Russian VLBI station. We determined the coordinates and velocity of the Svetloe VLBI station with errors of ～2 mm and 3 mm yr^?1, respectively, and the baseline lengths between the stations with a sufficiently long observational history with an accuracy of 1–3 mm. The results are shown to be in good agreement with currently available models for the motion of tectonic plates.     

On the variational approach to the periodic n-body problem

This expository paper gathers some of the results obtained by the author in recent works in collaboration with Davide Ferrario and Vivina Barutello, focusing on the periodic n-body problem from the perspective of the calculus of variations and minimax theory. These researches were aimed at developing a systematic variational approach to the equivariant periodic n-body problem in the two and three-dimensional space. The purpose of this paper is to expose the main problems and achievements of this approach. The material here was exposed in the talk that given at the Meeting CELMEC IV promoted by SIMCA (Società italiana di Meccanica Celeste).     

Critical inclination in the main problem of a massive satellite

The classical problem of the critical inclination in artificial satellite theory has been extended to the case when a satellite may have an arbitrary, significant mass and the rotation momentum vector is tilted with respect to the symmetry axis of the planet. If the planet’s potential is restricted to the second zonal harmonic, according to the assumptions of the main problem of the satellite theory, two various phenomena can be observed: a critical inclination that asymptotically tends to the well known negligible mass limit, and a critical tilt that can be attributed to the effect of transforming the gravity field harmonics to a different reference frame. Stability of this particular solution of the two rigid bodies problem is studied analytically using a simple pendulum approximation.     

Photometric Studies of Bright Southern Binary Systems: ε Cra and ψ Ori

We present results from detailed analyses of new data combined with previously published light curves of ε Cra and ψ Ori. Based on the shape of the secondary minimum of ε CrA we found that the discrepancy between the photometric and spectroscopic mass ratio, although marginal, is statistically significant. We propose a third light as a possible solution and derive the absolute parameters of components. The physical parameters of components of the early-type binary system ψ Ori were also obtained from the light curve modelling. Our solution indicate that ψ Ori is a detached, grazing-eclipse system.