Zobrazeno 1 - 10
of 91
pro vyhledávání: '"Nizamov, B. A."'
Autor:
Pshirkov, M. S., Nizamov, B. A.
Various theoretical models predict existence of extended gamma-ray halo around normal galaxies, that could be produced by interactions of cosmic rays with the circumgalactic medium or by annihilation or decay of hypothetical dark matter particles. Ob
Externí odkaz:
http://arxiv.org/abs/2410.02066
Autor:
Nizamov, B. A., Pshirkov, M. S.
The origin of the diffuse gamma-ray background in the range from hundreds keV to several MeV is not known conclusively. From current models and observations it is believed that, at least partially, this background is formed by blazars and remnants of
Externí odkaz:
http://arxiv.org/abs/2403.08427
Autor:
Nizamov, B. A., Pshirkov, M. S.
Positron annihilation line at 511~keV is a known component of the gamma-ray diffuse emission. It is believed to be produced in the Galaxy, but there could be possible extragalactic contribution as well. E.g., positrons can be produced in jets of acti
Externí odkaz:
http://arxiv.org/abs/2303.03526
Publikováno v:
Geomagnetism and Aeronomy, 2022, Volume 62, No. 7, Pages 903-910
We analyze various tracers of magnetic activity for 23 solar twins which are characterized by significant scatter of lithium abundance in their atmospheres. A level of coronal and chromospheric activity has been studied from available X-ray and UV-ar
Externí odkaz:
http://arxiv.org/abs/2212.10142
Autor:
Nizamov, B. A., Pshirkov, M. S.
Publikováno v:
Monthly Notices of the Royal Astronomical Society, Volume 520, Issue 3, April 2023, Pages 4456-4462
High-energy radiation of young pulsar wind nebulae (PWNe) is known to be variable. This is most prominently exemplified by the Crab nebula which can undergo both rapid brightenings and dimmings. Two pulsars in the Large Magellanic Cloud, PSR J0540-69
Externí odkaz:
http://arxiv.org/abs/2208.03820
Publikováno v:
MNRAS 496 (2020) 5227-5232
The giant gamma-ray flares of the Crab nebula discovered by AGILE and Fermi observatories came as a surprise and have challenged the existing models of pulsar wind nebulae. We have carried out an analysis of 10.5 years of Fermi-LAT observations (Aug
Externí odkaz:
http://arxiv.org/abs/2004.03964
Autor:
Nizamov, B. A.
Superflares on the solar type stars observed by \textit{Kepler} demonstrate the contrast in the optical continuum of the order 0.1--1 per cent. The mechanism of formation of this radiation is not firmly established. We consider a model where the stel
Externí odkaz:
http://arxiv.org/abs/1905.05054
Autor:
Katsova, M. M., Nizamov, B. A.
Publikováno v:
Geomagnetism and Aeronomy, 2018, Vol. 58, No. 7
We analyze physical characteristics of late-type stars wherein the Kepler mission registered superflares. We use the revised stellar fundamental parameters, i.e. effective temperatures Teff and surface gravitational accelerations log g, from the Kepl
Externí odkaz:
http://arxiv.org/abs/1812.09580
Autor:
Grechnev, V. V., Kiselev, V. I., Kashapova, L. K., Kochanov, A. A., Zimovets, I. V., Uralov, A. M., Nizamov, B. A., Grigorieva, I. Yu., Golovin, D. V., Litvak, M. L., Mitrofanov, I. G., Sanin, A. B.
Publikováno v:
This is a pre-print of an article published in Solar Physics, 2018, 293, 133. The final authenticated version is available online at: https://doi.org/10.1007/s11207-018-1352-z
The SOL2014-09-01 far-side solar eruptive event produced hard electromagnetic and radio emissions observed with detectors at near-Earth vantage points. Especially challenging was a long-duration >100 MeV $\gamma$-ray burst probably produced by accele
Externí odkaz:
http://arxiv.org/abs/1808.10103
Autor:
Nizamov, B. A., Pshirkov, M. S.
Publikováno v:
JCAP03(2020)060
It is well known that if the most energetic cosmic rays ($E>10^{20}$ eV) were protons then their acceleration sites should possess some extreme properties, including gigantic luminosity. As no stationary sources with such properties are known in the
Externí odkaz:
http://arxiv.org/abs/1804.01064