scholarly journals Evolution of Neutron Stars in Young Supernova Remnants

1983 ◽  
Vol 101 ◽  
pp. 509-512
Author(s):  
K. Nomoto ◽  
S. Tsuruta

The exciting observational developments in recent years (see Seward, Helfand, Harnden, Becker, etc., in this volume) have made it worthwhile to reexamine neutron star cooling theories. Here we shall give an intermediate report on our work.

1987 ◽  
Vol 125 ◽  
pp. 456-456
Author(s):  
Ken'ichi Nomoto ◽  
Sachiko Tsuruta

We have calculated cooling models of young neutron stars.3 The theoretical cooling curves for several models are compared with the Einstein X-ray observations of young supernova remnants (Figure 1).


1971 ◽  
Vol 46 ◽  
pp. 394-406
Author(s):  
F. Pacini

The Crab Nebula pulsar conforms to the model of a rotating magnetised neutron star in the rate of energy generation and the exponent of the rotation law.It is suggested that the main pulse is due to electrons and the precursor to protons. Both must radiate in coherent bunches. Optical and X-ray radiation is by the synchrotron process.The wisps observed in the Nebula may represent the release of an instability storing about 1043 erg and 1047–48 particles.Finally, some considerations are made about the general relation between supernova remnants and rotating neutron stars.


2017 ◽  
Vol 13 (S337) ◽  
pp. 213-216
Author(s):  
Wynn C. G. Ho ◽  
Nils Andersson ◽  
Vanessa Graber

AbstractA superconductor of paired protons is thought to form in the core of neutron stars soon after their birth. Minimum energy conditions suggest that magnetic flux is expelled from the superconducting region due to the Meissner effect, such that the neutron star core retains or is largely devoid of magnetic fields for some nuclear equation of state and proton pairing models. We show via neutron star cooling simulations that the superconducting region expands faster than flux is expected to be expelled because cooling timescales are much shorter than timescales of magnetic field diffusion. Thus magnetic fields remain in the bulk of the neutron star core for at least 106 − 107yr. We estimate the size of flux free regions at 107yr to be ≲ 100m for a magnetic field of 1011G and possibly smaller for stronger field strengths.


1983 ◽  
Vol 101 ◽  
pp. 513-516
Author(s):  
Kenneth A. Van Riper

Neutron star cooling calculations are reported which employ improved physics in the calculation of the temperature drop through the atmosphere. The atmosphere microphysics is discussed briefly. The predicted neutron star surface temperatures, in the interesting interval 300 ≤ t (yr) ≤ 105, do not differ appreciably from the earlier results of Van Riper and Lamb (1981) for a non-magnetic star; for a magnetic star, the surface temperature is lower than in the previous work. Comparison with observational limits show that an exotic cooling mechanism such as neutrino emission from a pion-condensate or in the presence of percolating quarks, is not required, unless the existence of a neutron star in the Tycho or SN1006 supernova remnants is established.


1987 ◽  
Vol 125 ◽  
pp. 457-457
Author(s):  
F.R. Harnden

For years the theoretical models of neutron star formation and evolution had remained largely unconstrained by observation. Following the Einstein X-ray Observatory surveys of supernova remnants and pulsars, however, strict temperature limits were placed on many putative neutron stars. The Einstein search for additional objects in the class of supernova remnants with embedded pulsars has increased the number of such objects by two. For the four objects in this class, the surface temperature limits (see Table 1) provide meaningful logically sound constraints on the neutron star models. For the future, however, still better X-ray observations are needed, both to increase the number of objects available for study and to refine the spatial and spectral capabilities of the X-ray measurements.


1981 ◽  
Vol 95 ◽  
pp. 339-341
Author(s):  
N. Itoh ◽  
K. Nomoto ◽  
S. Tsuruta ◽  
T. Murai

Most of the neutron star cooling calculations with the only exception of Malone's (1974) have assumed an isothermal stellar core. Here we report on a neutron star cooling calculation which makes full use of the stellar evolution code and the recent thermal conductivity calculations by Flowers and Itoh (1976, 1979).


Author(s):  
Akira Dohi ◽  
Ken’ichiro Nakazato ◽  
Masa-aki Hashimoto ◽  
Matsuo Yasuhide ◽  
Tsuneo Noda

Abstract Whether fast cooling processes occur or not is crucial for the thermal evolution of neutron stars. In particular, the threshold of the direct Urca process, which is one of the fast cooling processes, is determined by the interior proton fraction $Y_p$, or the nuclear symmetry energy. Since recent observations indicate the small radius of neutron stars, a low value is preferred for the symmetry energy. In this study, simulations of neutron star cooling are performed adopting three models for the equation of state (EoS): Togashi, Shen, and LS220 EoSs. The Togashi EoS has been recently constructed with realistic nuclear potentials under finite temperature, and found to account for the small radius of neutron stars. As a result, we find that, since the direct Urca process is forbidden, the neutron star cooling is slow with use of the Togashi EoS. This is because the symmetry energy of Togashi EoS is lower than those of other EoSs. Hence, in order to account for observed age and surface temperature of isolated neutron stars with the use of the Togashi EoS, other fast cooling processes are needed regardless of the surface composition.


1986 ◽  
Vol 64 (4) ◽  
pp. 474-478 ◽  
Author(s):  
Eric D. Feigelson

The evidence for jets emanating from neutron stars is reviewed. Isolated radio pulsars do not appear to produce collimated outflows. A few supernova remnants, notably the Crab nebula, exhibit jetlike protrusions at their outer boundaries. These are probably "blowouts" of the plasma in the remnant rather than true jets from a neutron star. However, several cases of degenerate stars in X-ray binary systems do make jets. SS433 has twin precessing jets moving outward at v ~ 0.26c, and Sco X-1 has radio lobes with v ~ 0.0001c. Cyg X-3 appears to eject synchrotron plasmoids at high velocities. Other X-ray binaries associated with variable radio sources are discussed; some are interesting candidates for collimated outflow. G109.1-1.0 is an X-ray binary in a supernova remnant that may have radio or X-ray jets. It is not clear in all these cases, however, that the compact object is a neutron star and not a black hole or white dwarf.A tentative conclusion is reached that isolated neutron stars do not produce jets, but degenerate stars in accreting binary systems can. This suggests that the presence of an accretion disk, rather than the characteristics of an isolated pulsar's dipole magnetosphere, is critical in making collimated outflows.


2020 ◽  
Vol 496 (4) ◽  
pp. 5052-5071 ◽  
Author(s):  
A Y Potekhin ◽  
D A Zyuzin ◽  
D G Yakovlev ◽  
M V Beznogov ◽  
Yu A Shibanov

ABSTRACT Ages and thermal luminosities of neutron stars, inferred from observations, can be interpreted with the aid of the neutron star cooling theory to gain information on the properties of superdense matter in neutron-star interiors. We present a survey of estimated ages, surface temperatures, and thermal luminosities of middle-aged neutron stars with relatively weak or moderately strong magnetic fields, which can be useful for these purposes. The catalogue includes results selected from the literature, supplemented with new results of spectral analysis of a few cooling neutron stars. The data are compared with the theory. We show that overall agreement of theoretical cooling curves with observations improves substantially for models where neutron superfluidity in stellar core is weak.


2020 ◽  
Vol 498 (1) ◽  
pp. 344-354 ◽  
Author(s):  
J-B Wei ◽  
G F Burgio ◽  
H-J Schulze ◽  
D Zappalà

ABSTRACT We model the cooling of hybrid neutron stars combining a microscopic nuclear equation of state in the Brueckner–Hartree–Fock approach with different quark models. We then analyse the neutron star cooling curves predicted by the different models and single out the preferred ones. We find that the possibility of neutron p-wave pairing can be excluded in our scenario.


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