Astronomers
continue to fight over the mystery superbright supernova. Supernovae can
suddenly shine brighter entire galaxy - in fact in this outbreak are killed
biggest stars. There are two types of supernovae. First appear, when one of the
stars of the binary system begins to pull stuff from a neighbor, and eventually
gaining critical mass.
Second direct from the biggest stars, almost infinite
reservoir of fuel to continue thermonuclear reaction from the collapse of its
core, hot and rich in heavy elements. It is a type II supernova explosions show
extraordinary strength, power ... and beauty.
However, over
the past few years have seen several cases in which supernovae have been
another couple of orders of magnitude brighter and more powerful than others.
They are so far recorded in a separate group of "super-bright supernova»
(Super-Luminous Supernovas, SLSN), though now we see that they themselves are
divided into three separate groups - and only one of them at least we can
roughly describe the mechanism of development events.
This is very
rare group superbright supernova, named SLSN-R, fueled by radioactive
processes. It is thought that creates the core of their collapse logged the
biggest stars, rich radioactive isotope of nickel stocks in times greater than
the mass of the Sun. Decays, it emits gamma radiation and produces a particle
of antimatter, which is, after all, an explosion and flash.
On the other
hand, it is unclear how and why these stars are so impressive stock of
radioactive nickel. He may have formed during the collapse of a massive star's
core especially. Perhaps it is a product of fusion reactions involving oxygen
flowing in the biggest stars.
More often
possible to observe superbright supernova another type of hydrogenation
SLSN-II. They are, as far as we know, are generated by the stars with a
particularly thick outer hydrogen envelope, so dense that significantly block
the light of stars (and difficult to observe them until the very moment when
the supernova was not "came shooting"). Trigger, triggering an
explosion in this case is the appearance of a number of the black hole or
magnetar - a word, a body powerful enough to dramatically intervene in the life
of the hydrogen to "cover" the star. In short, as the Israeli
astronomer Avishay Gal-Yam (Avishay Gal-Yam), «it is technically a type II
supernova, but does not arise from a red supergiant, as all of them, and some
of the other stars."
But the
brightest super bright supernovae are poor hydrogen SLSN-I. That is the origin
and essence remains a complete mystery. There is a hypothesis that generates
their stars, "swollen" to incredible size, ten times bigger than our
sun. Deprived of the hydrogen envelope, such stars shine especially brightly.
This possibility can be described at least in theory, and suggested that the
Gal-Yam and his colleagues.
According to
them, the source SLSN-I can serve as Star Wolf - Rayet star, a very high
temperature and luminosity. During the collapse of the core of such a star in
it can form a young magnetar , a neutron star, a rapidly spinning and having
incredibly powerful magnetic field. This embryo pumps crumbling energy star,
causing the appearance of the supernova brightness and incredible strength.
This scheme of
events, however, remains purely hypothetical. The authors themselves note that
ambiguity here begin with the first step - for example, remains unknown whether
the neutron star, just born in the core of a dying star Wolf - Rayet stars, rotate
fast enough to give the process the required amount of energy.
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