MAIK/NAUKA commended by this award the papers by
V.S.Imshennik and D.V.Popov "An Analytic Model for the Evolution of a
Close Binary System of Neutron (Degenerate) Stars" (Astronomy
Letters, 1998, v.24, p.251) and by A.G.Aksenov, E.A.Zabrodina,
V.S.Imshennik, and D.K.Nadyozhin "A Hydrodynamic Two-Dimensional
Model for an Asymmetric Explosion of Collapsing Supernovae with Rapid
Initial Rotation" (Astronomy Letters, 1997, v.23, p.779).
The explosions of type-II supernovae are thought to be associated with
gravitational collapse of the iron core in a massive star (M > 10
Mo), which takes place at a certain stage of its
evolution. During the explosion, a neutron star or a black hole is
formed, and an enormous amount of energy (of about 5 x 1053
erg/s) is released. However, calculations of the collapse show that
virtually all the energy is carried away by neutrinos within the first
seconds after the explosion, and that it is not possible to explain
where the kinetic energy of the expanding envelope and the energy
radiated away at optical and ultraviolet wavelengths (a total of about 1
x 1051 erg/s) come from in terms of the spherically symmetric
The authors of these papers suggested that the supernova-explosion
mechanism could be associated with rapid rotation of the neutron star
which forms during collapse. This mechanism was developed and tested
by the authors in their series of papers under the common title
"Rotational Explosion Mechanism for Collapsing Supernovae" (a
total of six papers) which were published in (Soviet) Astronomy Letters
in 1992-1998. The above two papers are the key papers of the series.
The proposed explosion scenario assumes the following sequence of events:
One side effect of such an explosion could be bursts of gamma-ray
radiation, which can account for the so-called cosmic gamma-ray bursts,
which are currently monitored and studied extensively worldwide.
- Collapse of the iron core in a massive star to produce a
dynamically unstable, rapidly rotating neutron star.
- Breakup of the neutron star into fragments, in particular, the
formation of a binary system of neutron stars.
- Gravitational radiation of the system and energy and
angular-momentum losses as the two stars approach each other, which
results in mass transfer and a mutual change in the stellar masses.
- Mass loss by one (low-mass) of the stars to a critical value of
about 0.1 Mo and the subsequent explosion.
- The formation and expansion of a rapidly moving cloud of "iron"
gas, which produces a shock wave and triggers a supernova explosion.
Annual competitions for the best publication are held by MAIK/NAUKA since
1995 and involve more than 100 scientific journals. There are 5 first
(main) and 50 second (small) awards.
May 25, 1999