Related papers: The Electron Temperature Gradient in the Galactic …
The central galaxies of some clusters can be strong emitters in the Ly$\alpha$ and H$\alpha$ lines. This emission may arise either from the cool/warm gas located in the cool core of the cluster or from the bright AGN within the central…
We report one of the first extragalactic observations of electron temperature variations across a spiral arm. Using MUSE mosaic observations of the nearby galaxy NGC 1672, we measure the [N II]5755 auroral line in a sample of 80 HII regions…
Recent X-ray observations by the space mission Chandra confirmed the astonishing evidence for a diffuse, hot, thermal plasma at a temperature of 9. $10^7$ K (8 keV) found by previous surveys to extend over a few hundred parsecs in the…
Using ACS-HST images to yield continuum subtracted photometric maps in H\alpha of the Sbc galaxy M51 and the dwarf irregular galaxy NGC 4449, we produced extensive (over 2000 regions for M51, over 200 regions for NGC4449) catalogues of…
The Galactic center region near l$\approx0.2^0$ hosts a mixture of nonthermal linear filaments and thermal radio continuum features associated with the radio Arc. Chandra observations of this region reveal an X-ray filament and diffuse…
Atomic hydrogen (HI) is a vital player in the star-formation process in galaxies. It is the raw fuel for making molecules, an important shielding agent against interstellar radiation, and a buffer that soaks up the energy and momentum of…
Cold gas clouds recently discovered hundreds of parsecs from the center of the Milky Way Galaxy have the potential to detect dark matter. With a detailed treatment of gas cloud microphysical interactions, we determine Galactic Center gas…
Spatial variations of the [S II]/H-Alpha and [N II]/H-Alpha line intensity ratios observed in the gaseous halo of the Milky Way and other galaxies are inconsistent with pure photoionization models. They appear to require a supplemental…
We derive infrared and radio flux densities of all ~1000 known Galactic HII regions in the Galactic longitude range 17.5 < l < 65 degree. Our sample comes from the Wide-Field Infrared Survey Explorer (WISE) catalog of Galactic \hii regions…
Aims: Temperature uncertainties plague our understanding of abundance variations within the ISM. Using the PHANGS-MUSE large program, we develop and apply a new technique to model the strong emission lines arising from HII regions in 19…
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…
Gas at high Galactic latitude is a relatively little-noticed component of the interstellar medium. In an effort to address this, forty-one Planck Galactic Cold Clumps at high Galactic latitude (HGal; $|b|>25^{\circ}$) were observed in…
We present an observational study about the impacts of the interactions in the electron density of \ion{H}{ii} regions located in 7 systems of interacting galaxies. The data consist of long-slit spectra in the range 4400-7300 A, obtained…
We examine the metallicity distribution of the Galactic thick disk using F, G, and K dwarf stars selected from the Sloan Digital Sky Survey, Data Release 8. Using the large sample of dwarf stars with proper motions and spectroscopically…
We present the results of a new sensitive survey of neutral hydrogen above and below the Galactic Center with the Green Bank Telescope. The observations extend up to Galactic latitude | b | < 10 deg with an effective angular resolution of…
HII regions are the ionized spheres surrounding high-mass stars. They are ideal targets for tracing Galactic structure because they are predominantly found in spiral arms and have high luminosities at infrared and radio wavelengths. In the…
The scattering diameters of Sgr A* and several nearby OH masers (~ 1" at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center. We combine radio-wave scattering data and free-free emission…
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 investigate structure of self-gravitating disks, their fragmentation and evolution of the fragments (the clumps) using both analytic approach and three-dimensional radiation hydrodynamics simulations starting from molecular cores. The…
Surrounding the Milky Way (MW) is the circumgalactic medium (CGM), an extended reservoir of hot gas that has significant implications for the evolution of the MW. We used the HaloSat all-sky survey to study the CGM's soft X-ray emission in…