arXiv subjects

Osmanov Zaza

Publications and source records attributed to Osmanov Zaza.

3 recordsLinked to original sources

arXiv2009

Centrifugally induced curvature drift instability in AGN

We investigate the centrifugally driven curvature drift instability to study how field lines twist close to the light cylinder surface of an AGN, through which the free motion of AGN winds can be monitored. By studying the dynamics of the relativistic MHD flow close to the light cylinder surface, we derive and solve analytically the dispersion relation of the instability by applying a single particle approach based on the centrifugal acceleration. Considering the typical values of AGN winds, it is shown that the timescale of the curvature drift instability is far less than the accretion process timescale, indicating that the present instability is very efficient and might strongly influence processes in AGN plasmas.

astro-ph.GA↗

arXiv2009

The Synchrotron Emission Mechanism in the Recently Detected Very High Energy Radiation from the Crab Pulsar

Interpretation of the recently discovered very high energy (VHE) pulsed emission from the Crab pulsar is presented. By taking into account the fact that Crab pulsar's radiation for the optical and VHE spectrum peak at the same phases, we argue that the source of this broad band emission is spatially localized. It is shown that the only mechanism providing the results of the MAGIC Cherenkov telescope, should be the synchrotron radiation. We find that in the magnetospheric electron-positron plasma, due to the cyclotron instability, the pitch angle becomes non-vanishing, which leads to the efficient synchrotron mechanism, intensifying on the light cylinder lengthscales. We also estimate the VHE radiation spectral index to be equal to -1/2.

astro-ph.HE↗

arXiv2009

On the very high energy (>25GeV) pulsed emission in the Crab pulsar

We have examined the recently detected very high energy (VHE) pulsed radiation from the Crab pulsar. According to the observational evidence, the observed emission (>25GeV) peaks at the same phase with the optical spectrum. Considering the cyclotron instability, we show that the pitch angle becomes non-vanishing leading to the efficient synchrotron mechanism near the light cylinder surface. The corresponding spectral index of the emission equals -1/2. By studying the inverse Compton scattering and the curvature radiation, it is argued that the aforementioned mechanisms do not contribute to the VHE radiation detected by MAGIC.

astro-ph.HE↗