Related papers: Kinematics of the Nebular Complex MH9/10/11 Associ…

Very sensitive 21cm HI measurements have been made at several locations around the Local Group galaxy M31 using the Green Bank Telescope (GBT) at an angular resolution of 9.1', with a 5$\sigma$ detection level of $\rm{N_{HI} = 3.9 \times…

We report the detection during the Chandra Orion Ultradeep Project (COUP) of two soft, constant, and faint X-ray sources associated with the Herbig-Haro object HH210. HH210 is located at the tip of the NNE finger of the emission line system…

Despite significant progress both observationally and theoretically, the origin of high-ionization nebular HeII emission in galaxies dominated by stellar photoionization remains unclear. Accretion-powered radiation from high-mass X-ray…

We present high resolution HST imaging of the nebula associated with the galactic LBV candidate HD 168625, together with ISO imaging and AAT echelle spectroscopy. The overall nebular morphology is elliptical with the major axis at PA ~ 120…

The large H II complex N11 in the Large Magellanic Cloud contains OB associations at several different stages in their life histories. We have obtained ROSAT PSPC and HRI X-ray observations, Curtis Schmidt CCD images, echelle spectra in…

We present an analysis of the kinematic and morphological structure of the nebula around the LMC LBV candidate S 119. On HST images, we find a predominantly spherical nebula which, however, seems to be much better confined in its eastern…

We present a detailed study of McNeil's nebula (V1647 Ori) in its ongoing outburst phase starting from September 2008 to March 2013. Our 124 nights of photometric observations were carried out in optical V, R, I and near-infrared J, H, K…

We present a new model for computing consistently the line and continuum emission from galaxies, based on a combination of recent population synthesis and photoionization codes. We use effective parameters to describe the HII regions and…

We present a study of the abundances and physical conditions in the interstellar gas toward the heavily reddened star HD 192639 [E_(B-V) = 0.64], based on analysis of FUSE and HST/STIS spectra covering the range from 912 to 1361 A. This…

We have performed a set of simulations of expanding, spherically symmetric nebulae inflated by winds from accreting black holes in ultraluminous X-ray sources (ULXs). We implemented a realistic cooling function to account for free-free and…

The central star of the Helix Nebula, WD 2226$-$210 presents enigmatic hard X-ray emission and mid-IR excess. The latter has been attributed to a dusty disk or a cloud-like structure around WD 2226$-$210 formed from material of Kuiper…

Using the VLBA, we have observed H2O maser emission in the pre-planetary nebula IRAS 19134+2131(I19134), in which the H2O maser spectrum has two groups of emission features separated in radial velocity by ~100 km/s. We also obtained optical…

We report medium resolution VLT ISAAC K-band spectroscopy of the nuclei of seven ultraluminous infrared galaxies. After accounting for stellar absorption features, we have detected several molecular hydrogen (H_2) v=1-0, 2-1, and 3-2…

We present Very Large Telescope/X-shooter and Chandra X-ray observatory/ACIS observations of the ULX [SST2011] J110545.62+000016.2 in the galaxy NGC 3521. The source identified as a candidate near-infrared counterpart to the ULX in our…

We construct orbit-based axisymmetric dynamical models for the globular cluster M15 which fit groundbased line-of-sight velocities and Hubble Space Telescope line-of-sight velocities and proper motions. This allows us to constrain the…

The nucleus of M87 displays a LINER spectrum at optical wavelengths, with a nuclear disk of nebulosity that is resolved by the Hubble Space Telescope. We present new results from optical and ultraviolet spectra of the central ~40pc as…

We present an all-sky catalog of diffuse O VII and O VIII line intensities, extracted from archival XMM observations. The O VII and O VIII intensities are typically ~2-11 and <~3 ph/cm^2/s/sr (LU), respectively, although much brighter…

We have obtained spectra for globular cluster candidates in M104 with LDSS-2 on the William Herschel Telescope, confirming 34 objects as M104 globular clusters. We find a cluster velocity dispersion of $\sim$ 260 km/sec, and the Projected…

This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, linked to the Wolf-Rayet star HD168206 (WR 113), and its relation to other components of its local interstellar medium. We…

Photoionization models of the giant HII region 30 Doradus are built and confronted to available UV, optical, IR (ISO) and radio spectra, under black-body or CoStar SEDs for the primary source and various density distributions for the…