Be X-Ray Binaries

Having already discussed the main connection between neutron stars (NS’s) as being pre-cursors to Supernova Explosions (SNE’s), when they are found as X-ray pulsars in close binary systems (Cen X-3, Her X-1), we can now turn to the pre-cursors of the pre-cursors.

First, the direct pre-cursors of a major class of supernova explosions are O-stars, which we assert are giant stars that have captured a neutron star which is currently in a close binary orbit with the O-star. The O-star is “super-bright” and this brightness or luminosity of upwards of 10**38 ergs/sec (more than 100,000 times the brightness of the Sun) is caused by the gravitational and magnetic fields of the neutron star which pulls in the atmosphere of the companion which then radiates in powerful X-rays.

In many O-stars, the neutron star has already been pulled down into the atmosphere of the O-star and the X-rays it emits are absorbed by the O-star atmosphere and re-radiated at lower energies, which gives the O-star its apparent brightness.

However, this state of the neutron star being in a close binary orbit of its companion is the late stage of the pre-supernova phase. In earlier stages, just after the initial capture of the neutron star by the giant star, the neutron star is in a highly elliptical orbit, which begins after its first encounter with the giant star.

As the neutron star has repeated collisions with the giant star, each time it completes its elliptical orbit, the dimensions of the ellipse begin to shrink until the orbit becomes circular.

It is this intermediate stage where the orbit is still elliptical, which is the significance of the Be X-ray binaries.

There is plentiful evidence for this intermediate stage as found with the Be X-ray binaries. These binaries have the following properties:

• a neutron star orbiting a Be companion with a highly elliptical orbit
• the neutron star spin rate (pulsar rate) is relatively slow compared to radio pulsars (1 sec -> 1,000 sec)
• the spin rate of the neutron star is generally getting faster, correlated with encounters with the companion during which the neutron star absorbs part of the Be star’s atmosphere and emits x-rays while accreting this material

A good reference for Be X-ray binaries is:
“On the neutron star–disc interaction in Be/X-ray binaries” Pablo Reig
Mon. Not. R. Astron. Soc. 377, 867–873 (2007)

The assertion here is that this class of x-ray binary will eventually (within approx 1 million years) evolve into a close binary O-star. This appears to be inevitable, because the per-orbit encounters with the Be star are going to continue and each encounter further circularizes the orbit. When the orbit is fully circularized and the neutron star begins burrowing into the atmosphere of the Be star, it will either look like Cen X-3 or simply a very bright O-star, where the neutron star is below the surface and the pulses are not readily visible, except possibly when there are atmospheric blow-offs of the outer material.

The Be X-ray binaries also provide a point of contrast with the ns-creation theory that claims that neutron stars are created by a pre-cursor star that explodes in a supernova, and creates a rapidly rotating neutron star as a pulsar. In the binary case, the precursor would need to be a normal pair of stars in a binary system, where one of the stars experienced a supernova explosion to become a rapidly rotating neutron star giving off radio signals.

The first problem with this scenario is that the rapidly rotating star (10 or more times per second) would need to slow down into the 1s->1000s time per rotation of the Be X-ray binaries. It would be difficult for the Neutron Star to slow down, since encounters with the remaining companion would tend to further speed up the rotation rate.

In addition, to the best of my knowledge there are no known examples of highly elliptic radio pulsars in orbit around a companion, and generally no binary radio pulsars at all except in a couple of anomalous cases, which we will address separately.

Therefore, since there are no known pre-cursors to the Be X-ray binary systems, we must again ask:
“Where did the neutron star come from?”

The only answer appears to be that the neutron star came from space, randomly encountered the Be-star, and became bound, which is the NS-Capture theory.

So, we now have a fairly complete picture of how the NS-Capture theory explains the creation of both the O-star supergiant X-ray binaries and the Be-star X-ray binaries, along with a logical evolutionary path that enables the Be X-ray binaries to evolve into the O X-ray binaries.

We will also find with further analysis that in order to produce the observed number of these high mass X-ray binary systems that there must be on the order of 5 trillion neutron stars (NS’s) currently in the Milky Way galaxy intermingled with the normal stars (Regular Stars: RS’s) at a ratio on the order of 25NS:1RS.
Of course, the same model applies to all galaxies, not just the Milky Way.