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1.
Astronomy Letters - The birth function of neutron stars in magnetic field $$B$$ is estimated for two models of the evolution of radio pulsars corresponding to different directions of evolution of... 相似文献
2.
We consider the properties of electric and magnetic fields in vacuum in the neighborhood of static, spherically symmetric
wormholes. Although certain aspects of this problem have been considered before, some important features remained undiscovered.
We study in detail the properties of electric and magnetic fields in the case of quasi-adiabatic motion of field sources near
an Ellis-Bronnikov wormhole and the passage of such sources through the wormhole. An exact solution is found in closed form
for a wormhole immersed in a magnetic field that is homogeneous at infinity, as well as an exact solution for a dipolar field
without sources. The properties of electromagnetic fields are important for possible observational manifestations of wormholes
in astrophysics. 相似文献
3.
G. M. Beskin S. V. Karpov A. V. Biryukov S. F. Bondar E. A. Ivanov E. V. Katkova N. V. Orekhova A. V. Perkov V. V. Sasyuk 《Astrophysical Bulletin》2017,72(1):81-92
We describe the properties of Mini-MegaTORTORA (MMT-9) nine-channel wide-field optical sky monitoring system with subsecond temporal resolution. This instrument can observe sky areas as large as 900 deg2, perform photometry in three filters close to Johnson BV R system and polarimetry of selected objects or areas with 100–300 deg2 sizes. The limiting magnitude of the system is up to V = 11m for 0.1 s temporal resolution, and reaches V = 15m in minute-long exposures. The system is equipped with a powerful computing facility and dedicated software pipeline allowing it to perform automatic detection, real-time classification, and investigation of transient events of different nature located both in the near- Earth space and at extragalactic distances. The objects routinely detected by MMT-9 include faint meteors and artificial Earth satellites.We discuss astronomical tasks that can be solved using MMT-9, and present the results of the first two years of its operation. In particular, we report the parameters of the optical flare detected on June 25, 2016, which accompanied the gamma-ray burst GRB160625B. 相似文献
4.
G. Beskin N. Borisov V. Komarova S. Mitronova S. Neizvestny V. Plokhotnichenko M. Popova 《Astrophysics and Space Science》1997,248(1-2):51-57
I summarize fully-sampled observations of the 3 mm emission from CO and HCN in the inner arcminute of NGC 1068. The CO emission
is distributed in the form of a molecular bar, coincident with the infrared bar, from which emanate two spiral arms. A relatively
weak concentration of CO line emission is found at the nucleus. By contrast, the HCN emission is strongly concentrated at
the center, with relatively weak emission in the region of the star-forming arms. The ratio of HCN to CO integrated intensities
is about 0.6 over the central r ≉ 175 pc and is the highest ratio measured in the center of any galaxy; the ratio reflects
the high thermal pressure (TK ~ 50 K, n[H2] ~ 4 × 106 cm-3) in the few hundred parsecs surrounding the nucleus.
The kinematics in the star-forming arms are well described by circular orbits, with ordered noncircular motions of < 30 km
s-1 that may be attributed to spiral density wave streaming. Interior to the bar, noncircular motions dominate the gas kinematics.
A model of the CO kinematics contrains any Inner Lindblad Resonance to be close to the location of the hundred-parsec scale
HCN ‘disk’. At the nucleus, the spatially unresolved CO emission shows a triplet velocity structure characteristic of kinematically
independent regions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
The measurements of pulsar frequency second derivatives have shown that they are 102−106 times larger than expected for standard pulsar spin-down law, and are even negative for about half of pulsars. We explain
these paradoxical results on the basis of the statistical analysis of the rotational parameters ν,
and
of the subset of 295 pulsars taken mostly from the ATNF database. We have found a strong correlation between
and
for both
and
, as well as between ν and
. We interpret these dependencies as evolutionary ones due to
being nearly proportional to the pulsars’ age. The derived statistical relations as well as “anomalous” values of
are well described by assuming the long-time variations of the spin-down rate. The pulsar frequency evolution, therefore,
consists of secular change of ν
ev(t),
and
according to the power law with n≈5, the irregularities, observed within a timespan as a timing noise, and the variations on the timescale larger than that—several
decades.
This work has been supported by the Russian Foundation for Basic Research (grant No 04-02-17555), Russian Academy of Sciences
(program “Evolution of Stars and Galaxies”), and by the Russian Science Support Foundation. The authors would also like to
thank the anonymous referee for valuable comments. 相似文献
6.
A simple analytical model of the particle-dominated outflow with zero total electric current from central rotating objects is considered. 'Exact' solutions for both relativistic and non-relativistic cases demonstrate the decollimation of the magnetic field lines in the region of the current closure. Such a decollimation can explain the presence of an energetic equatorial wind observed in many compact objects. 相似文献
7.
A method of determination of limits for a compact component mass on the base of disk emission lines parameters is described. Lower limit of the mass depends upon the distance between maxima in double peaked lines, the upper the full width of the line. The method is tested for some cataclysmic variables with well known masses of compact components. We obtain a lower limit for the mass of the compact object in the close binary SS433 is 4.9M
. This component is apparently a black hole. 相似文献
8.
G. Beskin S. Karpov S. Bondar A. Guarnieri C. Bartolini D. Greco A. Piccioni 《Astrophysical Bulletin》2010,65(3):223-229
The results of observations of the optical emission that accompanied the gamma-ray burst GRB 080319B are reported. Observations
were made using the TORTORA fast wide-field camera mounted on the REM robotic telescope in Chile. The behavior of the light
curve before, during, and after the gamma-ray burst is described. The light curve consists of four, possibly periodic, 5–7
s long peaks 8–9 s apart. The behavior of the burst in the gamma and optical energy ranges are compared and the results of
the theoretical interpretation of this comparison are reported. 相似文献
9.
10.
We explore the possibilities for detecting pulsars that have ceased to radiate in the radio band. We consider two models: the model with hindered particle escape from the pulsar surface [first suggested by Ruderman and Sutherland (1975)] and the model with free particle escape (Arons 1981; Mestel 1999). In the model with hindered particle escape, the number of particles that leave the pulsar magnetosphere is small and their radiation cannot be detected with currently available instruments. At the same time, for Arons' model, both the number of particles and the radiation intensity are high enough for such “extinct” pulsars to be detectable with the GLAST and INTEGRAL satellites. 相似文献