We model the radio, optical, and X-ray emission for the afterglows of GRB 980703, 990123, 990510, and 991216, within the framework of relativistic jets, to determine their physical parameters. The models that yield acceptable fits to the data have jet energies mostly between 10 to 10 erg and initial opening angles between 1 and 4. The external medium density is uncertain by at least one order o...

We analyzed the zero-order image of a 50 ks Chandra gratings observation of Circinus X-1, taken in 2005 during the source’s low-flux state. Circinus X-1 is an accreting neutron star that exhibits ultra-relativistic arcsecond-scale radio jets and diffuse arcminute-scale radio jets and lobes. The image shows a clear excess along the general direction of the north-western counter-jet, coincident w...

The protostellar outflow is star’s first cry at the moment of birth. The outflows have indispensable role in the formation of single stars, because they carry off the excess angular momentum from the centre of the shrinking gas cloud, and permits further collapse to form a star. On the other hand, a significant fraction of stars is supposed to be born as binaries with circumbinary disk that are...

Galactic winds from starbursts and Active Galactic Nuclei (AGN) are thought to play an important role in driving galaxies along the starburst-AGN sequence. Here, we assess the impact of these winds on the CO emission from galaxy mergers, and, in particular, search for signatures of starburst and AGN-feedback driven winds in the simulated CO morphologies and emission line profiles. We do so by c...

High-resolution SiO observations of the NGC 1333 IRAS 4A star-forming region showed a highly collimated outflow with a substantial deflection. The deflection was suggested to be caused by the interactions of the outflow and a dense cloud core. To investigate the deflection process of protostellar outflows, we have carried out threedimensional hydrodynamic simulations of the collision of an outf...

Collapse of the rotating magnetized molecular cloud core is studied with the axisymmetric magnetohydrodynamical (MHD) simulations. Due to the change of the equation of state of the interstellar gas, the molecular cloud cores experience several different phases as collapse proceeds. In the isothermal run-away collapse (n ∼< 10 H2 cm ), a pseudo-disk is formed and it continues to contract till th...

The Trifid nebula is a young HII region undergoing a burst of star formation. In this article, we report on far-infrared and millimeter continuum and line observations of several massive and bright protostellar sources in the vicinity of the exciting star of the nebula, just behind the ionization front. These objects are probably young protostars (Class 0) and are associated with very massive c...

We present unpublished Spitzer IRAC observations of the HH 1/2 young stellar outflow processed with a high angular resolution deconvolution algorithm , that produces sub-arcsecond (∼ 0.6 0.8′′) images. In the resulting mid-infrared images, the optically invisible counterjet is detected for the first time. The counterjet is approximately half as bright as the jet at 4.5μm (the IRAC band that bes...

We present Submillimter Array 1.3 mm waveband continuum and molecular line observations of the HH 80–81 high-mass star-forming region. The dust continuum emission reveals two dominant peaks MM1 and MM2, and line emission from high-density tracers suggests the presence of another core MC. Molecular line emission from MM1, which harbors the exciting source of the HH 80–81 radio jet, yields a hot ...

Transverse stratification is a common intrinsic feature of astrophysical jets. There is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis, surrounded by a slower, denser, extended jet. The inner and outer jet components then have a different origin and launching mechanism, making their effective inertia, magnetization, associated energy flux and ...