arXiv subjects

Ahmadjon Abdujabbarov

Publications and source records attributed to Ahmadjon Abdujabbarov.

94 records · Page 6Linked to original sources

arXiv2011

Magnetized Particle Capture Cross Section for Braneworld Black Hole

Capture cross section of magnetized particle (with nonzero magnetic moment) by braneworld black hole in uniform magnetic field is considered. The magnetic moment of particle was chosen as it was done by \citet{rs99} and for the simplicity particle with zero electric charge is chosen. It is shown that the spin of particle as well as the brane parameter are to sustain the stability of particles circularly orbiting around the black hole in braneworld i.e. spin of particles and brane parameter try to prevent the capture by black hole.

astro-ph.SR↗

arXiv2011

Particle Motion around Black Hole in Horava-Lifshitz Gravity

Analytical solutions of Maxwell equations around black hole immersed in external uniform magnetic field in the background of the Kehagias-Sfetsos (KS) asymptotically flat black hole solution of Hořava-Lifshitz gravity have been found. Influence of magnetic field on effective potential of the radial motion of charged test particle around black hole immersed in external magnetic field in Hořava-Lifshitz gravity has been investigated by using Hamilton-Jacobi method. Exact analytical solution for dependence of the minimal radius of the circular orbits $r_{\rm mc}$ from KS parameter $ω$ for motion of test particle around spherical symmetric black hole in Hořava-Lifshitz gravity has been derived. The critical values of the particle's angular momentum for captured particles by black hole in Hořava-Lifshitz gravity have been obtained numerically. The comparison of the obtained numerical results with the astrophysical observational data on radii of the innermost stable circular orbits gives us the estimation of the parameter as $ω\simeq 3.6 \cdot 10^{-24} {\rm cm}^{-2}$.

gr-qc↗

arXiv2010

Quantum Interference Effects in Horava-Lifshitz Gravity

The relativistic quantum interference effects in the spacetime of slowly rotating object in the Hořava-Lifshitz gravity as the Sagnac effect and phase shift of interfering particle in neutron interferometer are derived. We consider the extension of Kehagias-Sfetsos (KS) solution~\cite{ks09} in the Hořava-Lifshitz gravity for the slowly rotating gravitating object. Using the covariant Klein-Gordon equation in the nonrelativistic approximation, it is shown that the phase shift in the interference of particles includes the gravitational potential term with the KS parameter $ω$. It is found that in the case of the Sagnac effect, the influence of the KS parameter $ω$ is becoming important due to the fact that the angular velocity of the locally non rotating observer is increased in Hořava gravity. From the results of the recent experiments~\cite{holgeretal} we have obtained lower limit for the coupling KS constant as $ω\simeq 1.25 \cdot 10^{-25} \rm{cm}^{2}$. Finally, as an example, we apply the obtained results to the calculation of the UCN (ultra-cold neutrons) energy level modification in the gravitational field of slowly rotating gravitating object in the Hořava-Lifshitz gravity.

gr-qc↗

arXiv2009

Charged Particle Motion Around Rotating Black Hole in Braneworld Immersed in Magnetic Field

Analytical solutions of Maxwell equations in background spacetime of black hole in braneworld immersed in external uniform magnetic field have been found. Influence of both magnetic and brane parameters on effective potential of the radial motion of charged test particle around slowly rotating black hole in braneworld immersed in uniform magnetic field has been investigated by using Hamilton-Jacobi method. Exact analytical solution for dependence of the radius of the innermost stable circular orbits (ISCO) $r_{\rm ISCO}$ from brane parameter for motion of test particle around nonrotating isolated black hole in braneworld has been derived. It has been shown that radius $r_{\rm ISCO}$ is monotonically growing with the increase of module of brane tidal charge. Comparison of the predictions on $r_{\rm ISCO}$ of the brane world model and of the observational results of ISCO from relativistic accretion disks around black holes provided upper limit for brane tidal charge $\lesssim 10^9 {\rm cm}^2$.

gr-qc↗