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Outflows are common in many astrophysical systems. In the Two Component Advective Flow ({fontfamily{qcr}selectfont TCAF}) paradigm which is essentially a generalized Bondi flow including rotation, viscosity and cooling effects, the outflow is originated from the hot, puffed up, post-shock region at the inner edge of the accretion disk. We consider this region to be the base of the jet carrying away matter with high velocity. In this paper, we study the spectral properties of black holes using {fontfamily{qcr}selectfont TCAF} which includes also a jet ({fontfamily{qcr}selectfont JeTCAF}) in the vertical direction of the disk plane. Soft photons from the Keplerian disk are up-scattered by the post-shock region as well as by the base of the jet and are emitted as hard radiation. We also include the bulk motion Comptonization effect by the diverging flow of jet. Our self-consistent accretion-ejection solution shows how the spectrum from the base of the jet varies with accretion rates, geometry of the flow and the collimation factor of the jet. We apply the solution to a jetted candidate GS,1354-64 to estimate its mass outflow rate and the geometric configuration of the flow during 2015 outburst using {it NuSTAR} observation. The estimated mass outflow to mass inflow rate is $0.12^{+0.02}_{-0.03}$. From the model fitted accretion rates, shock compression ratio and the energy spectral index, we identify the presence of hard and intermediate spectral states of the outburst. Our model fitted jet collimation factor ($f_{rm col}$) is found to be $0.47^{+0.09}_{-0.09}$.
We study the spectral and timing properties of a two component advective flow (TCAF) around a black hole by numerical simulation. Several cases have been simulated by varying the Keplerian disk rate and the resulting spectra and lightcurves have been
We study several Galactic black hole candidates using long-time RXTE/ASM X-ray data to search for telltale signatures of differences in viscous timescales in the two components used in the Two-Component Advective Flow (TCAF) paradigm. In high-mass X-
The fundamental difference between accretion around black holes and neutron stars is the inner boundary condition, which affects the behavior of matter very close to the compact objects. This leads to formation of additional shocks and boundary layer
A black hole accretion may have both the Keplerian and the sub-Keplerian component. In the so-called Chakrabarti-Titarchuk scenario, the Keplerian component supplies low energy (soft) photons while the sub-Keplerian component supplies hot electrons w
High-energy emission of extragalactic objects is known to take place in relativistic jets, but the nature, the location, and the emission processes of the emitting particles are still unknown. One of the models proposed to explain the formation of re