Related papers: Hercules stream and the outer elliptical ring R1R2
We present the first detailed study of the large, ~30 pc diameter, inner-Galaxy HII region W 39. Radio recombination line observations combined with HI absorption spectra and Galactic rotation models show that the region lies at V(LSR) =…
RCB stars are $L\approx10^4\,L_{\odot}$ solar-mass objects that can exhibit large periods of extinction from dust ejection episodes. Many exhibit semiregular pulsations in the range of $30-50$ days with semi-amplitudes of $0.05-0.3$…
The magnetic cataclysmic variable DQ Herculis was observed with the Faint Object Spectrograph onboard the Hubble Space Telescope (HST) over four consecutive satellite orbits, including the first observation in the UV of DQ Her through…
There is a class of binary post-AGB stars with a remarkable near-infrared excess that are surrounded by Keplerian or quasi-Keplerian disks and extended outflows composed of gas escaping from the disk. The Keplerian dynamics had been well…
AR Herculis is an RR Lyrae star of type RRab whose spectral type ranges from A7 to F3. Its visual brightness varies between 10.59 mag and 11.63 mag (V). By analysis of 34,000 measurements from the AAVSO International Database and additional…
We present measurements of interstellar H_2 absorption lines in the continuum spectra of seven early-type stars in the Galactic disk at distances between 1 and 4 kpc. Five of these stars provide lines of sight through the Sagittarius spiral…
We have mapped the powerful radio galaxy Hercules A at six frequencies spanning 1295 to 8440 MHz using the VLA in all four configurations. Here we discuss the structure revealed in total intensity, spectral index, polarization, and…
We present the physical and evolutionary properties of prestellar and protostellar clumps in the Herschel Infrared GALactic plane survey (Hi-GAL) in two large areas centered in the Galactic plane and covering the tips of the long Galactic…
The Helix Nebula (NGC 7293) is the closest planetary nebulae. Therefore, it is an ideal template for photochemical studies at small spatial scales in planetary nebulae. We aim to study the spatial distribution of the atomic and the…
Cold stellar streams---produced by tidal disruptions of clusters---are long-lived, coherent dynamical features in the halo of the Milky Way. Due to their different ages and different positions in phase space, different streams tell us…
The present paper is the culminating one of a series aimed to contribute to the understanding of the kinematic structures of the solar neighbourhood (SN), explaining the origin of the Local Arm and relating the moving groups with the…
We present a comprehensive analysis of a broad band spectral line survey of the Orion Kleinmann-Low nebula (Orion KL), one of the most chemically rich regions in the Galaxy, using the HIFI instrument on board the Herschel Space Observatory.…
We investigate the kinematic properties of Galactic HII regions using radio recombination line (RRL) emission detected by the Australia Telescope Compact Array (ATCA) at 4-10 GHz and the Jansky Very Large Array (VLA) at 8-10 GHz. Our HII…
We present a new spectroscopic study of the dwarf galaxy Hercules (d ~ 132 kpc) with data from the Anglo-Australian Telescope and its AAOmega spectrograph together with the Two Degree Field multi-object system to solve the conundrum that…
We use a combination of spatial distribution and radial velocity to search for halo sub-structures in a sample of 412 RR Lyrae stars (RRLS) that covers a $\sim 525$ square degrees region of the Virgo Overdensity (VOD) and spans distances…
We present mid-infrared interferometric observations of the Herbig Ae star R CrA obtained with MIDI at the VLTI using several projected baselines in the UT2-UT3 configuration. The observations show resolved circumstellar emission in the…
We report Keck LRIS observations of an arc-like background galaxy near the center of Abell 2152 (z=0.043), one of the three clusters comprising the Hercules supercluster. The background object has a redshift z=0.1423 and is situated 25…
We develop a new method for simulating stellar streams generated by globular clusters using angle-action coordinates. This method reproduces the variable mass-loss and variable frequency of the stripped stars caused by the changing tidal…
The results are presented of an extensive programme of optical and infrared imaging of radio sources in a complete subsample of the Leiden-Berkeley Deep Survey. The LBDS Hercules sample consists of 72 sources observed at 1.4 GHz, with flux…
We present Herschel PACS spectroscopy of the [OI] 63 micron gas-line for three circumstellar disk systems showing signs of significant disk evolution and/or planet formation: HR 8799, HD 377 and RX J1852.3-3700. [OI] is undetected toward HR…