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Next: Other
Candidates for Ejecting Up: Ejectors
in Massive Binary Previous: Why
must a radiopulsar
It seems at first glance that a binary system is not the most likely
place for an ejecting NS to exist: the dense stellar wind absorbs coherent
radiowaves and reduces the lifetime of the star at the ejection stage.
This is indeed the case. However, there is another important factor which
helps (from the point of view of observation) in distinguishing NS in a
binary system from a single NS. It should be recalled that most (99.99
percent) of the energy is dissipated by single radiopulsars in the form
of relativistic particles and low-frequency electromagnetic waves which
are not observable. In the case of a binary system, however, the normal
star may trap a considerable part of the relativistic wind ( 
, where 
is the radius of the normal star) and convert it into a form in which it
can be detected on the Earth. This gives rise to an interesting analog
of the classical reflection or heating effect (Lipunov, 1980[97];
Lipunov and Prokhorov, 1984[110];
Harding, 1991[64]; Lipunov and Nazin,
1994[119]). The main mechanisms
of energy conversion are the synchrotron radiation of relativistic particles
in the magnetic field of a normal star and nuclear transformation of ultrahigh-energy
particles colliding with the stellar wind matter of
the same star.
The total power of the energy of relativistic particles transformed in this way is estimated from
where 
is the characteristic size of the capture region expressed in units of
the semi-major axis ( 
). For close binary systems, 
-0.3 and the transformation coefficient may
be several percent.
Apart from the reflection effect, transient floating and bursting of caverns, or the radioburster phenomenon, may also be observed.
An ejector in a pair with a normal star can appear as a new phenomenon - an induced radiopulsator. Synchrotron radioemission of relativistic particles captured by the magnetic field of the optical star must be strictly periodic in nature due to the rotation of a normal star (Lipunov and Nazin, 1993, 1994).[118, 119] The period of an induced radiopulsator may be confined in the interval of some hours to some days.