We study the survival probability for long times in an open spherical billiard, extending previous work on the circular billiard. We provide details of calculations regarding two billiard configurations, specifically a sphere with a circular hole and a sphere with a square hole. The constant terms of the long-time survival probability expansions have been derived analytically. Terms that vanish...

We consider the effects of eccentricity on the fragmentation of gravitationally unstable accretion disks, using numerical hydrodynamics. We find that eccentricity does not affect the overall stability of the disk against fragmentation, but significantly alters the manner in which such fragments accrete gas. Variable tidal forces around an eccentric orbit slow the accretion process, and suppress...

Local scour around a cylindrical pier in a channel with an erodible bed or natural bed is a common problems in bridge or pile supported structure. The highly unsteady complex flow field around a circular pier produces scour hole mainly for the presence of vortices. The main mechanism that drives the formation and evolution of the scour hole around bridge pier is horse shoe vortex motion. In the...

Gravitational waves from ~90 black hole binary systems have been detected and their progenitors' properties inferred1 so far by the Laser Interferometer Gravitational-Wave Observatory2 Virgo3 experiments. This has allowed scientific community to draw conclusions on formation channels of holes in binaries, informing population models at times defying our understanding astrophysics. The most chal...

The double nucleus geometry of M31 is currently best explained by the eccentric disk hypothesis of Tremaine, but whether the eccentric disk resulted from the tidal disruption of an inbounding star cluster by a nuclear black hole, or by an m = 1 perturbation of a native nuclear disk, remains debatable. I perform detailed 2-D decomposition of the M31 double nucleus in the Hubble Space Telescope V...

we report a unique case of chronic dissection of the ascending aorta complicated with huge and thrombotic pseudoaneurysm in a patient with coarctation of descending aorta. preoperative investigations such as transesophageal echocardiography (tee) confirmed the diagnosis of dissection. intraoperative findings included a12 cm eccentric bulge of the right lateral side of dilated the ascending aort...