The Hubble Deep Fields continue to be a valuable resource for studying the distant universe, particularly at z > 2 where their comoving volume becomes large enough to encompass several hundred L∗ galaxies or their progenitors. Here I present recent results from a near–infrared imaging survey of the HDF–North with NICMOS, which provides structural and photometric information in the optical rest ...

Gravitational signals emitted by a point mass orbiting a neutron star: effects of stellar structure. Abstract The effects that the structure of a neutron star would have on the gravita-tional emission of a binary system are studied in a perturbative regime, and in the frequency domain. Assuming that a neutron star is perturbed by a point mass moving on a close, circular orbit, we solve the equa...

We have found the stellar populations of early-type galaxies are homogeneous with no significant difference in color or Mg2 index, despite the dichotomy between X-ray extended early-type galaxies and X-ray compact ones. Since the X-ray properties reflect the potential gravitational structure and hence the process of galaxy formation, the homogeneity of the stellar populations implies that the f...

The rotation curves of a sample of 46 low- and high-surface brightness galaxies are considered in the context of Milgrom's modi_ed dynamics (MOND) to test a new interpolating function proposed by Zhao et al. (2010) [1] and compare with the results of simple interpolating function. The predicted rotation curves are calculated from the total baryonic matter based on the B-band surface photometry,...

We have investigated the e ects of primeval starbursts on the galactic structure, showing that the dynamical structure of young galaxies is changed by relaxation of a stellar system formed by a starburst-driven out owing gas (superwind). When a superwind interacts with halo gas, an expanding dense supershell of shocked gas is formed. Using a similarity solution for the expanding shell and a con...

Gravitational signals emitted by a point mass orbiting a neutron star: effects of stellar structure. Abstract The effects that the structure of a neutron star would have on the gravita-tional emission of a binary system are studied in a perturbative regime, and in the frequency domain. Assuming that a neutron star is perturbed by a point mass moving on a close, circular orbit, we solve the equa...

We present a new mechanism for Type Ia supernova explosions in massive white dwarfs. The proposed scenario follows from relaxing the assumption of symmetry in the model and involves a detonation created in an unconfined environment. The explosion begins with an essentially central ignition of stellar material initiating a deflagration. This deflagration results in the formation of a buoyantly-d...