Plasma experiments conducted on the PF-1000 device generate the release of neutrons and ionizing radiation that are the source of immediate exposure to personnel. Neutron activation of materials in the research device and the surroundings is a source of ongoing radiation exposure to the same personnel. Having reported on personnel exposure from ionizing radiation and neutron activation, we now ...

Using recently calculated analytic and numerical models for the thermal structure of ultramagnetized neutron stars, we estimate the effects that ultrastrong magnetic fields B ≥ 10 G have on the thermal evolution of a neutron star. Understanding this evolution is necessary to interpret models that invoke “magnetars” to account for soft γ-ray emission from some repeating sources. Subject headings...

A delicate interplay between the anomalous magnetic moments of the proton and neutron makes, in magnetic fields B ≥ 2 × 10 T, the neutron stable and for fields B ≥ 5 × 10 T the proton becomes unstable to a decay into a neutron via β emission. Limits on the field strengths for which these arguments hold are presented and are related to questions of vacuum stability in the presence of such fields...

A new classification of neutron star cooling scenarios, involving either “minimal” cooling or “enhanced” cooling is proposed. The minimal cooling scenario replaces and extends the so-called standard cooling scenario to include neutrino emission from the Cooper pair breaking and formation process. This emission dominates that due to the modified Urca process for temperatures close to the critica...

Low mass X–ray transients hosting black hole candidates display on average a factor of ∼ 100 larger swing in the minimum (quiescent) to maximum (outburst) X–ray luminosity than neutron star systems, despite the fact that the swing in the mass inflow rate is likely in the same range. Advection dominated accretion flows, ADAFs, were proposed to interpret such a difference, because the advected en...

A number of Anomalous X-ray Pulsars (AXPs) have recently been detected in the optical/IR wavelengths. We use their inferred brightness to place general constraints on any model for this emission within the magnetar framework. We find that neutron-star surface emission cannot account for the observations and that the emission must be magnetospheric in origin. We propose a model for the optical/I...

In the atmospheric plasma of a strongly magnetized neutron star, vacuum polarization can induce a Mikheyev-Smirnov-Wolfenstein type resonance across which an x-ray photon may (depending on its energy) convert from one mode into the other, with significant changes in opacities and polarizations. We show that this vacuum resonance effect gives rise to a unique energy-dependent polarization signat...

In polarized neutron decay, the angular correlation between the neutron spin and the direction of emission of the electron is characterized by the coefficient A. Measuring A involves determining the forward-backward asymmetry of the decay beta with respect to the direction of the neutron polarization. The value of A, when combined with measurements of the neutron lifetime, determines the values...

It is suggested that the persistent X-ray emission from the soft γ-ray repeaters is the thermal radiation of neutron stars which is enhanced by a factor of 10 or more due to the effect of a very strong magnetic field on the thermal structure of the neutron star envelope. For the thermal luminosity to be consistent with the persistent X-ray luminosity, the field strength at the neutron star surf...

Transient X-ray emission, with an approximate t−0.7 decay, was observed from SGR 1900+14 over 40 days following the the giant flare of 27 Aug 1998. We calculate in detail the diffusion of heat to the surface of a neutron star through an intense 1014 − 1015 G magnetic field, following the release of magnetic energy in its outer layers. We show that the power law index, the fraction of burst ener...