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O3 and CO from burning sugar cane

1989; Nature Portfolio; Volume: 339; Issue: 6222 Linguagem: Inglês

10.1038/339264a0

1476-4687

V. W. J. H. Kirchhoff, E. V. A. Marinho, Pedro Leite da Silva Dias, Roberto V. Calheiros, R. G. B. André, Cassandra J. Volpe,

Sugarcane Cultivation and Processing

moment-of-inertia tensor of PSR0535 -69 contains non-axisymmetric components !!!.I comparable to the irregular fluctuations in I, then the rate of gravitational quadrupole radiation is-10 43 (!!!.I,,)' erg s. (Here I 39 = I 110'' gem'.)The corresponding metric fluctuation at the Earth is h = w-zs !!!.I,,.The empirical bound on the period derivative imposes an upper bound of 5 X 10 43 I 45 erg s on the radiated power, unless it is offset by another process.The quadrupole power is radiated at the accurately known frequency 2v.Higher nonaxisymmetric multipole moments radiate at frequencies 3v, 4v and so on.The rapid spin of PSR0535-69, approaching the limiting angular velocity of neutron stars', naturally suggests that it was spun up to this limit when it was formed, and is now slowing by the emission of electromagnetic or gravitational radiation.Internal cooling by neutrino emission produces contraction and angular momentum-conserving spin up.Exchange of angular momentum with a differentially rotating core may lead to a period derivative with either sign, or to fluctuations.Differential internal rotation may heat the star.It is possible that the neutron star is surrounded by an accretion disk of matter left over from the supernova with excess angular momentum.Then, as angular momentum is radiated away, accretion will maintain the pulsar on the vm,(MNs) relation as MNS' the neutron-star mass, increases.As in accreting binary neutron stars, irregularities in angular-momentum transfer could produce irregular variations in v of the type observed.Accretion suggests the exciting possibility that the pulsar may be pushed over its limiting mass and collapse to a black hole or a more exotic configuration; the timescale would be determined by the (unknown) angular-momentum loss rate, and could be short.