27 citations · 104 across the 15 of their papers we have counts for
15 papers
Detection of Gamma-ray Halos around Nearby Late-type Galaxies
M. S. Pshirkov, B. A. Nizamov
Various theoretical models predict the existence of extended -ray halo around normal galaxies that could be produced by interactions of cosmic rays with the circumgalactic mediu…
Annihilation of positrons from AGN jets as a possible source of cosmic gamma-ray background at energies below 511 keV
B. A. Nizamov, M. S. Pshirkov
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…
Can observations of 511 keV line from the M31 galaxy shed light on the AGN jet composition?
B. A. Nizamov, M. S. Pshirkov
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…
Activity of Selected Solar Twins
M. M. Katsova, B. A. Nizamov, A. A. Shlyapnikov
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…
Gamma-ray flares from pulsar wind nebulae in the Large Magellanic Cloud
B. A. Nizamov, M. S. Pshirkov
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…
Multiwavelength Stereoscopic Observation of the May 1, 2013 Solar Flare and CME
Erica Lastufka, Säm Krucker, Ivan Zimovets +7
A M-class behind-the-limb solar flare on 1 May 2013 (SOL2013-05-01T02:32), accompanied by a ( 400 km/s) CME was observed by several space-based observatories with different v…
Gamma-ray flux depressions of the Crab nebula in the high-energy range
M. S. Pshirkov, B. A. Nizamov, A. M. Bykov +1
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…
Soft X-ray heating as a mechanism of optical continuum generation in solar-type star superflares
B. A. Nizamov
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 r…
Properties of Kepler Stars with the Most Powerful Flares
M. M. Katsova, B. A. Nizamov
We analyze physical characteristics of late-type stars wherein the Kepler mission registered superflares. We use the revised stellar fundamental parameters, i.e. effective temperat…
Radio, Hard X-Ray, and Gamma-Ray Emissions Associated with a Far-Side Solar Event
V. V. Grechnev, V. I. Kiselev, L. K. Kashapova +9
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…
Constraints on the AGN flares as sources of ultra-high energy cosmic rays from the Fermi-LAT observations
B. A. Nizamov, M. S. Pshirkov
It is well known that if the most energetic cosmic rays ( eV) were protons then their acceleration sites should possess some extreme properties, including gigantic lumin…
New estimation of non-thermal electron energetics in the giant solar flare on 28 October 2003 based on Mars Odyssey observations
B. A. Nizamov, I. V. Zimovets, D. V. Golovin +5
A new estimation of the total number and energy of the non-thermal electrons produced in the giant () solar flare on 2003 October 28 is presented based on the analysis…
Catalog of Hard X-ray Solar Flares Detected with Mars Odyssey/HEND from the Mars Orbit in 2001-2016
M. A. Livshits, I. V. Zimovets, D. V. Golovin +7
The study of nonstationary processes in the Sun is of great interest, and lately, multiwavelength observations and registration of magnetic fields are carried out by means of both…
Change in activity character of coronae of low-mass stars of various spectral types
B. A. Nizamov, M. M. Katsova, M. A. Livshits
We study the dependence of the coronal activity index on the star's rotation rate. This question was considered earlier for 824 late-type stars on the basis of a consolidated catal…
Superflare G and K Stars and the Lithium abundance
M. M. Katsova, M. A. Livshits, T. V. Mishenina +1
We analyzed here the connection of superflares and the lithium abundance in G and K stars based on Li abundance determinations conducted with the echelle spectra of a full set of 2…