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31.
A. V. Gurevich Ya. N. Istomin 《Monthly notices of the Royal Astronomical Society》2007,377(4):1663-1667
The analysis of observations of pulsar B1931+24 shows that the mechanism of the spin-down of a rotating magnetized neutron star is due to the plasma generation in its magnetosphere and, consequently, the radio emission generation. The unique observation of the switch on and switch off of this pulsar allows us to distinguish between the energy loss in the absence of radio emission (the magnetodipole radiation) and the current loss due to the rotation energy expenditure to the relativistic plasma generation and acceleration in the pulsar magnetosphere. The inclination angle χ, the angle between the rotation axis and the magnetic dipole axis, can be stationary for this pulsar, χ=χst . From observations and theory it follows that χst = 59° . 相似文献
32.
The motion of electrons and positrons in the vacuum magnetosphere of a neutron star with a surface magnetic field of B ≈ 1012 G is considered. Particles created in the magnetosphere or falling into it from outside are virtually instantaneously accelerated
to Lorentz factors γ ≈ 108. After crossing the force-free surface, where the projection of the electric field onto the magnetic field vanishes, a particle
begins to undergo ultra-relativistic oscillations. The particle experiences a regular drift along the force-free surface simultaneous
with this oscillatory motion. 相似文献
33.
Y. N. Istomin 《Astrophysics and Space Science》2011,331(1):127-133
We predict the synchrotron radiation from transient pulsars. The radiation is generated under the interaction of the magneto-dipole
radiation with the relativistic electron-positron wind just after switching off of a radio pulsar. We calculate the spectrum
and the flux of this radiation. The synchrotron radiation is estimated to observe from two nulling pulsars B1929+10 and B0656+14
on the level of several tens mJansky. The observed bright spiky emission of B0656+14 by Weltevrede et al. (Astron. Astrophys.
458:269, 2006) allows us to suggest that it has synchrotron nature. Observation of the synchrotron radiation gives possibility to determine
the pulsar magnetic field and parameters and geometry of the pulsar wind. 相似文献
34.
The connection between the radio emission from “lightnings” produced by the absorption of high-energy photons from the cosmic
gamma-ray background in a neutron star magnetosphere and radio bursts from rotating ratio transients (RRATs) is investigated.
The lightning length reaches 1000 km; the lightning radius is 100 m and is comparable to the polar cap radius. If a closed
magnetosphere is filled with a dense plasma, then lightnings are efficiently formed only in the region of open magnetic field
lines. For the radio emission from a separate lightning to be observed, the polar cap of the neutron star must be directed
toward the observer and, at the same time, the lightning must be formed. The maximum burst rate is related to the time of
the plasma outflow from the polar cap region. The typical interval between two consecutive bursts is ∼100 s. The width of
a single radio burst can be determined both by the width of the emission cone formed by the lightning emitting regions at
some height above the neutron star surface and by a finite lightning lifetime. The width of the phase distribution for radio
bursts from RRATs, along with the integrated pulse width, is determined by the width of the bundle of open magnetic field
lines at the formation height of the radio emission. The results obtained are consistent with the currently available data
and are indicative of a close connection between RRATs, intermittent pulsars, and extreme nullers. 相似文献
35.
Observational data are analysed on the basis of pulsar magnetosphere theory and the Ruderman-Sutherland plasma generation mechanism. The results of theory and experiment are shown to be in good agreement. The existence of a special group of long-lived, weakly-radiating fast (the periodP0.1–0.4 s) and superfast (P0.01) pulsars is predicted. 相似文献
36.
The similarities in certain empirical relations derived for active galactic nuclei (AGN) and radio pulsars support the idea that the energy release in the jets of AGN is electrodynamical, associated with the presence of a massive central object (MCO) and circumnuclear, magnetized Keplerian disk. For example, in both types of object, the radio luminosities are proportional to characteristic time scales—for precession for AGN or rotation for pulsars—to the 0.8 power. In this approach to studying the nature of the activity, the $\dot P - P$ relation for pulsars can be considered analogous to the P r-M MCO relation for AGN, which has the form P 5GHz (W/Hz)=2.73 log(M MCO/M ⊙)?2.87. 相似文献
37.
Ya. Istomin 《Astrophysics and Space Science》2001,278(1-2):77-80
We have developed a numerical code for the propagation of different electromagnetic modes in a pulsar magnetosphere filled
by a relativistic, streaming electron-positron plasma in a strong, curved magnetic field. We determine the trajectories, limiting
polarization and damping of the waves leaving the magnetosphere.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献