A mechanism for the transition between low/hard, high/soft, and steep power law (SPL) spectral states in black hole X-ray binaries is proposed. The low/hard state is explained by the development of a magnetically arrested accretion disk attributable to the accumulation of a vertical magnetic field in a central bundle. This disk forms powerful jets and consists of thin spiral accretion streams o...

We study the peak energy (Ep) distribution of the νFν spectra of gamma-ray bursts (GRBs) and X-ray flashes (XRFs) with a sample of 57 bursts observed by High Energy Transient Explorer 2 (HETE2) French Gamma Telescope and discuss its implications for the jet structure models. Combining the observed Ep distribution of HETE–2 GRBs/XRFs with that of BATSE GRBs, we find that the observed Ep distribu...

SN 2001em, identified as a Type Ic supernova, has recently been detected in the radio and X-rays, & 2 yr after the explosion. The high luminosities at such late times might arise from a relativistic jet viewed substantially off-axis that becomes visible only when it turns mildly relativistic and its emission is no longer strongly beamed away from us. Alternatively, the emission might originate ...

The dynamics of GRB jets during the afterglow phase have an important effect on the interpretation of their observations and for inferring key physical parameters such as their true energy and event rate. Semi-analytic models generally predict a fast lateral expansion, where the jet opening angle asymptotically grows exponentially with its radius. Numerical simulations, however, show a much mor...

Accretion and outflows are common in systems which include compact objects such as black holes and neutron stars. In the last three decades, numerous models have been built to produce jets and outflows. In the case of black holes, since no matter can escape out of the horizon, some suggested that the jets are formed in the strong field region around black holes in the form of pair plasma (Type ...

In a previous paper (McGroarty & Ray, 2004) we examined the environment of a number of evolved low -mass young stars, i.e. Classical T Tauri Stars, to see if they are capable of driving parsec scale outflows. These stars CW Tau, DG Tau, DO Tau, HV Tau C and RW Aur were previously known to drive only “micro jets” or small scale outflows of ≤ 1′ or 0.04 pc at the distance of the Taurus Auriga Clo...

ABSTRACT We present a study of luminous, $z\, =\, 0.15$, type-2 quasar ($L_{[\rm O III]}$ = 1042.8 erg s−1) from the Quasar Feedback Survey. It is classified as ‘radio-quiet’ ($L_{\mathrm{1.4\, GHz}}$ 1023.8 W Hz−1); however, radio imaging reveals ∼ 1 kpc low-power jets (Pjet 1044 inclined into plane galaxy disc. combine MUSE and ALMA observations to map stellar kinematics ionized molecular gas...

We review recent progress in the theory of relativistic jet production in AGN and Micro-quasars. The current popular model for launching, accelerating and collimating astrophysical jets is based on magnetohydrodynamics (MHD). AGN jets are most probably powered by energy extracted from either an accretion disk or a rotating Black Hole. A strong electromagnetic field in the central engine, couple...

For the past decade, ionized outflows of a few 100 km s from nearby Seyfert galaxies have been studied in great detail using high resolution X-ray absorption spectra. A recurring feature of these outflows is their broad ionization distribution including essentially ions (e.g., of Fe) from neutral to fully ionized. The absorption measure distribution (AMD) is defined as the distribution of colum...