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[en] In this report, we first review earlier and recent developments in some of thermodynamic problems of neutron stars, especially those involving cooling mechanisms and theoretical predictions of surface temperatures of neutron stars. Emphasis is placed particularly on: the effect of equations, of state and hence that of nuclear and strong interactions; the effect of better treatment of various neutrino cooling mechanisms, especially those involving pion condensates; and implication of these better and more detailed theoretical estimates on the prospect of directly observing thermal radiation from the surface of neutron stars. In connection with the last problem, we briefly review recent developments on the observational side - the HEAO-B and other programs already existing or expected to be planned for near future, which are directly related to the above problem. In connection with the possibilities of observing older neutron stars we briefly summarise various heating mechanisms. (orig./WL
[en] We proposed an alternative explanation to the rapid cooling of neutron star in Cas A. It is suggested that the star experiences the recovery period following the r-mode heating process assuming the star is differentially rotating. Like the neutron-superfluidity-triggering model, our model predicts that the rapid cooling will continue for several decades. However, the behavior of the two models has slight differences, and they might be distinguished by observations in the near future.
[en] Observations of the rotational behaviour of pulsars have shed much light on the structure of neutron stars. In particular, the response of the Vela pulsar (PSR0833-45) following each of seven giant glitches (sudden increases in rotation rate ν of magnitude Δν./ν.≅ 10-6, and in the derivative, Δν/ν ≅10-2) has been a recovery on two timescales, of about 6 and 60 days. This has been interpreted as evidence for the existence of distinct regions of neutron superfluid within the stellar crust. Here I report observations that started 35 minutes after the eighth glitch of PSR0833-45, which reveal a hitherto unseen glitch component: a (12±1)% increase in the slowdown rate ν. (the largest so far seen), most of which decayed away over 0.4 days. These data support the existence of at least two superfluid components in the stellar crust that are coupled linearly to the normal crust. (author)
[en] The standard engine behind core-collapse supernovae is continuously evolving with increasingly detailed models. At this time, most simulations focus on an engine invoking turbulence above the proto-neutron star, sometimes termed the “convection-enhanced” engine. Finally, we review this engine and why it has become the standard for normal supernovae, focusing on a wide set of observations that provide insight into the supernova engine.