For a set S of vertices and the vertex v in a connected graph G, max x∈S d(x, v) is called the S-eccentricity of v in G. The set of vertices with minimum S-eccentricity is called the S-center of G. Any set A of vertices of G such that A is an S-center for some set S of vertices of G is called a center set. We identify the center sets of certain classes of graphs namely, Block graphs, Km,n, Kn −...

We report the discovery of a massive (Mp = 9.04±0.50MJup) planet transiting the bright (V = 8.7) F8 star HD 147506, with an orbital period of 5.63341±0.00013 days and an eccentricity of e = 0.520± 0.010. From the transit light curve we determine that the radius of the planet is Rp = 0.982± 0.105RJup. HD 147506b (also coined HAT-P-2b) has a mass about 9 times the average mass of previously-known...

Most extrasolar planets are observed to have eccentricities much larger than those in the solar system. Some of these planets have sibling planets, with comparable masses, orbiting around the same host stars. In these multiple planetary systems, eccentricity is modulated by the planets’ mutual secular interaction as a consequence of angular momentum exchange between them. For mature planets, th...

For a nonempty set S of vertices in a strong digraph D, the strong distance d(S) is the minimum size of a strong subdigraph of D containing the vertices of S. If S contains k vertices, then d(S) is referred to as the k-strong distance of S. For an integer k > 2 and a vertex v of a strong digraph D, the k-strong eccentricity sek(v) of v is the maximum k-strong distance d(S) among all sets S of k...

We report the discovery during the Parkes Multibeam Pulsar Survey of PSR J1756−2251, a 28.5 ms pulsar in a relativistic binary system. Subsequent timing observations showed the pulsar to have an orbital period of 7.67 hrs and an eccentricity of 0.18. They also revealed a significant advance of periastron, 2.585± 0.002 deg. yr. Assuming this is entirely due to general relativity implies a total ...

I propose that the relatively high eccentricity 0.1 ∼< e ∼< 0.4 found in some tidally strongly interacting binary systems, where the mass-losing star is an evolved giant star, e.g., an asymptotic giant branch star, is caused by an enhanced mass loss rate during periastron passages. Tidal interaction by itself will circularize the orbits of these systems in a relatively short time, hence a mecha...

ABSTRACT By means of high-resolution hydrodynamical, three-dimensional calculations with nested-meshes, we evaluate the eccentricity reached by a low-mass, luminous planet embedded in an inviscid disc constant thermal diffusivity and subjected to forces. We find that cell size at most 1/10th region heated is required get converged results. When planet’s luminosity supercritical, it reaches orde...

The differential migration of two planets due to planet-disk interaction can result in capture into the 2:1 eccentricity-type mean-motion resonances. Both the sequence of 2:1 eccentricity resonances that the system is driven through by continued migration and the possibility of a subsequent capture into the 4:2 inclination resonances are sensitive to the migration rate within the range expected...

the paper presents a mathematical base modeling combined to modified-winding -function-approach (mwfa) for eccentricity fault detection of a round-rotor synchronous machine. for this aim, a 6-pole machine is considered, and the machine inductances are computed by mwfa in healthy and also under eccentricity fault. a numerical discrete-time method has been proposed to machine modeling in voltage-...