We present the results of searches for EUV emission from neutron stars conducted with the EUVE Deep Survey and Scanner Telescopes. To date, 21 fields containing known neutron stars have been observed in the Lexan/Boron (40–190 Å ) band. Of these, 11 fields were simultaneously observed in the Aluminum/Carbon (160-385 Å ) band. Five neutron stars which have been detected in the EUV have been repo...

After a brief history of neutron stars and supernovae recent developments are discussed. Based on modern nucleon-nucleon potentials more reliable equations of state for dense nuclear matter have been constructed. Furthermore, phase transitions such as pion, kaon and hyperon condensation, superfluidity and quark matter can occur in cores of neutron stars. Specifically, the nuclear to quark matte...

The measurement or constraint of the masses of neutron stars and their binary companions tests theories of neutron star structure and of pulsar formation and evolution. We have measured the rate of the general relativistic advance of the longitude of periastron for the pulsar PSR B1802−07: ω̇ = 0. 060 ± 0. 009 yr, which implies a total system mass, pulsar plus companion star, of M = 1.7 ± 0.4M⊙....

We consider a simulated population of isolated Galactic neutron stars. The rotational frequency of each neutron star evolves through a combination of electromagnetic and gravitational wave emission. The magnetic field strength dictates the dipolar emission, and the ellipticity (a measure of a neutron star’s deformation) dictates the gravitational wave emission. Through both analytic and numeric...

We apply the statistical measure of complexity introduced by López-Ruiz, Mancini and Calbet [1] to neutron stars structure. Neutron stars is a classical example where the gravitational field and quantum behavior are combined and produce a macroscopic dense object. Actually , we continue the recent application of Sañudo and Pacheco [2] to white dwarfs structure. We concentrate our study on the c...

We report on the long term average spin period, rate of change of spin period and X-ray luminosity during outbursts for 42 Be X-ray binary systems in the Small Magellanic Cloud. We also collect and calculate parameters of each system and use this data to determine that all systems contain a neutron star which is accreting via a disc, rather than a wind, and that if these neutron stars are near ...

Combining resolved spectroscopy with deep imaging, XMM-Newton is providing new insights on the particle acceleration processes long known to be at work in the magnetospheres of isolated neutron stars. According to a standard theoretical interpretation, in neutron stars' magnetospheres particles are accelerated along the B field lines and, depending on their charge, they can either move outward,...

After some historical remarks we discuss different criteria of dynamical stability of stars, and properties of the critical states where dynamical stability is lost, leading to collapse with formation of the neutron star or a black hole. At the end some observational and theoretical problems related to quark stars are discussed. 1. Introduction It was first noted by S Chandrasekhar in 1931 that...

We present two-dimensional simulations for the cooling of neutron stars with strong magnetic fields (B ≥ 1013 G). We study how the cooling curves are influenced by magnetic field decay. We show that the Joule heating effects are very large and in some cases control the thermal evolution. We characterize the temperature anisotropy induced by the magnetic field and predict the surface temperature...

The existence of ultra-fast rotating neutron stars (spin period P ∼< 1 ms) is expected on the basis of current models for the secular evolution of interacting binaries, though they have not been detected yet. Their formation depends on the quantity of matter accreted by the neutron star which, in turn, is limited by the mechanism of mass ejection from the binary. An efficient mass ejection can ...