Properties of the NS-Capture Theory
Stepping back from the details forcing the use of the ns-capture theory, we can obtain a general understanding from the following model:
- Assume that interspersed among the regular stars in the galaxy that there are maybe 20 neutron stars for each regular star. This assumption is based on the calculation of the number of neutron stars required to be in the galaxy to account for populations of x-ray binaries.
- The relative proportion of neutron stars to regular stars remains in this constant proportion of 20:1 regardless of the density of visible stars. For example, in a very dense globular cluster there are still 20 neutron stars for every regular star in the cluster.
- All stars are in relative motion to each other. In general, stars can collide if they happen to approach too close to each other. This is a relatively rare occurrence between two regular stars.
- However, with 20x neutron stars as regular stars, the chances of collisions between a neutron star and a regular star are much greater than the chances of collisions for 2 regular stars. It is these neutron star <-> regular star collisions that can result in the binding the two star and the creation of an X-ray binary system.
- Once the x-ray binary is created, it can never be separated, however the neutron star will create so much heat in the ordinary star that it will eventually (about 1 million years) become gravitationally unstable, in the sense that the star’s gravitational self-binding energy is counteracted by the heat created by the neutron star. At this point the star will simply “fly apart” and will be aided in flying apart by the radiating pulsar that has been created at its center, which comes into existence as a result of the spin-up of the pulsar by accretion.
- There appear to be 2 major cases with respect to the endpoint of the x-ray binaries:
- The companion star totally flies apart leaving nothing behind but a giant cloud of gas, with a rapidly spinning pulsar near the center of the cloud.
- Only the outer atmosphere of the companion flies apart, leaving behind the core of the ordinary star in a tight binary orbit with the pulsar.
- The statistics of what kind of stars experience these binding collisions are basically that the bigger the regular star, the more likely it is to be hit by a neutron star. Therefore a disproportionately large percentage of X-ray binaries will be found to be giant stars (GS’s), simply because shooting in the dark, it is more likely to hit a giant than a normal size star.
- i.e. consider 2 square boxes, 1 light year on a side. One box contains a regular star (RS), and the other contains a giant star (GS). It is about 10 times more likely that a NS randomly traveling through the GS-box will collide with the GS in that box, than it is likely that random NS would collide with the RS in the RS-box. i.e. if you shot 1 million NS’s through the GS-box, you would get 10 times as many hits as you would if you shot 1 million NS’s through the RS-box.
- Therefore, all kinds of regular stars will be found as companions in x-ray binary systems, but a larger fraction of those binaries will contain a giant than the fraction of giant stars in the overall stellar population.
- In the total destruction supernova events, the pulsar travels through the exploding cloud with a velocity inherited from its orbital velocity just before its companion blew apart.
Many of the properties above are derived from the fact the GS’s are easier to hit with a random shot than RS’s. That is probably why there are relatively more x-ray binary systems with GS companions, like Cen X-3 and the BeXB’s, as opposed to systems like Her X-1 and some small mass XRB’s, where the companion is typically a normal size star (RS).
i.e. the main property described here is that of the total population of stars in the galaxy there is a ratio of GS:RS stars. However, because of the random capture mechanism the resulting ratios of GSXRB’s:RSXRB’s binaries is significantly larger than the GS:RS ratio for isolated stars.
Finally, much of the focus of this site is on the Giant X-ray Binaries (High Mass X-ray Binaries (HMXB’s)). It turns out that by analyzing the giants alone we are able to prove NS-Capture for all types of x-ray binaries, because we are focused on how the systems form as opposed to their specific behavior resulting from the capture based on companion type.
The bottom line is that, if we prove that the NS’s in the x-ray binaries were not the result of NS’s created by a SNE, but instead the result of an NS capture, then it seems superfluous to attempt to claim that the NS’s in other contexts are created by GS-implosions. i.e. if we prove there are trillions of NS’s in the galaxy that have always been there, we hardly need a mechanism to create another NS from one of the visible stars.