Star forming regions are expected to show linear proper motions due to the relative motion of the Sun with respect to the region. These proper motions appear superposed to the proper motions expected in features associated with mass ejection from the young stellar objects embedded in them. Therefore, it is necessary to have a good knowledge of the proper motions of the region as a whole in orde...

Cepheus E is the site of an exceptional example of a protostellar outflow with a very young dynamical age and extremely high near infrared luminosity. We combine molecular spectroscopic data from the submillimeter to the near infrared in order to interpret the rotational excitation of CO and the ro-vibrational excitation of H2. We conclude that C-type shocks with a paraboloidal bow shock geomet...

We report on a signal-to-noise–limited search for low-ionization gas outflows in the spectra of the 0.11 < z < 0.54 objects in the Extended Groth Strip (EGS) portion of the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey. Doppler shifts from the host galaxy redshifts are systematically searched for in the Na I λ 5890,96 doublet (Na I D). Although the spectral resolution and signal-to-noi...

Using the Very Large Array, we have detected weak OH maser emission near the Turner–Welch protostellar source in the W3 OH region. Unlike typical interstellar OH masers, which are associated with ultra-compact HII regions, our measured positions and proper motions (from Very Long Baseline Interferometry) indicate that these OH masers are associated with a bipolar outflow traced by strong H2O ma...

Recent discovery of the afterglow emission from short gamma-ray bursts suggests that binary neutron star or black hole-neutron star binary mergers are the likely progenitors of these short bursts. The accretion of neutron star material and its subsequent ejection by the central engine implies a neutron-rich outflow. We consider here a neutron-rich relativistic jet model of short bursts, and inv...

The low luminosity radio emission of the unusually faint GRB 031203 has been argued to support the idea of a class of intrinsically sub-energetic gamma-ray bursts (GRBs), currently comprising two members. While low energy GRBs probably exist, we show that the collective prompt and multiwavelength observations of the afterglow of GRB 031203 do not necessarily require a sub-energetic nature for t...

We present the results of 2.5-dimensional resistive magnetohydrodynamic (MHD) simulations of the magnetic interaction between a weakly magnetized neutron star and its accretion disk. General relativistic effects are simulated by using the pseudo-Newtonian potential. We find that well-collimated jets traveling along the rotation axis of the disk are formed by the following mechanism: (1) The mag...

We report VIMOS integral field spectroscopy of the N159F nebula surrounding LMCX-1. Our observations reveal a rich, extended system of emission line filaments lining the boundary of a large conical cavity identified in Spitzer mid-IR imaging. We find that X-ray photoionization cannot be solely responsible for the observed ionization structure of N159F. We propose that the extended filamentary e...

The synchrotron self-Compton (SSC) emission from Gamma-ray Burst (GRB) forward shock can extend to the very-high-energy (VHE; Eγ >100 GeV) range. Such high energy photons are rare and are attenuated by the cosmic infrared background before reaching us. In this work, we discuss the prospect to detect these VHE photons using the current ground-based Cherenkov detectors. Our calculated results are...

Recently a correlation between the radio and X-ray luminosities is found, LR ∝ L 0.7 X , in black hole sources including black hole candidates in our galaxy and active galactic nuclei. We first attempt to understand the correlation in the context of an accretion-jet model developed for explaining the spectral and timing properties of XTE J1118+480. We find that this model can explain the observ...