We consider the Blandford-Znajek (BZ) mechanism for extracting black hole spin energy to drive astrophysical jets. Analyses of BZ generally take no account any electric charge on hole. But, as noted by Wald and others, if medium surrounding is an ionized plasma with mobile charges, then a spinning quickly acquires charge. The effect this nullify field structures which mechanism. Since jets are ...

Metal spinning as a kind of manufacturing process has capability to shape hollow components. In present work shear spinning process is used to formplates into conical shapes. Moreover, the aim of this research is to demonstrate the impact of the process parameters (i.e. feeding rate and spindle speed) on wall thickness. This approachwas done by experimental and finite elements method. The resul...

Young protostars embedded in circumstellar discs accrete from an angular momentum rich mass reservoir. Without some braking mechanism, all stars should be spinning at or near breakup velocity. In this paper, we perform simulations of the self-gravitational collapse of an isothermal cloud using the ORION adaptive-mesh refinement code and investigate the role that gravitational torques might play...

in this article using comparative multi-purpose algorithm of pso, optimum capacity of new resources and their spinning storage is defined. spinning reserve requirements and optimized to maximize profit per unit is determined according to uncertainty. in fact by increasing the level of cost reservation, power supply increases but penalty of blackout decreases. in this paper in has been tried to ...

X-ray quasi-periodic eruptions (QPEs) are discovered recently in active galaxies with unknown driven mechanism. Under the assumption that QPEs caused by star-disc collisions, we adopt full relativistic method and show both orbital parameters of star also mass spinning massive black hole (MBH) can be revealed using time arrival (TOA) QPEs. By applying model to observed GSN069, find is a near-cir...

background & importance: disc herniation is defined as the prolapsed of material disc into the spinal canal. if the disc fragment is free in spinal canal, it is called sequestration disc fragment. occasionally, alteration in sequestration disc fragment makes the diagnosis of the disc herniation, challenging. case presentation: we reviewed a rare case of the cervical sequestrated disc herniation...

ABSTRACT Accreting supermassive binary black holes (SMBBHs) are potential targets for multimessenger astronomy as they emit gravitational waves (GW) while their environment emits electromagnetic (EM) waves. In order to get the most out of a joint GW–EM detection we first need obtain theoretically predicted EM signals unambiguously linked BBHs. that respect, this is series papers dedicated accre...

The study of the quasi-periodic oscillations (QPOs) X-ray flux observed in stellar-mass black hole (BH) binaries or quasars can provide a powerful tool for testing phenomena occurring strong gravity regime. We thus fit data QPOs well known as microquasars framework model geodesic Keplerian disks modified epicyclic spinning test particles orbiting Kerr BHs. show that models explain observational...