Velocity profiles of [CII], [CI], CO, and [OI] and physical conditions in four star-forming regions in the Large Magellanic Cloud

We report the first velocity-resolved observations of atomic oxygen in the Large Magellanic Cloud (LMC) seen in emission lines at a wavelength of 63 and 145 micrometers. The line profiles neither match those from ionized carbon nor from carbon monoxide. This confirms that clouds in very different physical conditions co-exist within the observing beam.

The Origin of [C II] 158 μm Emission toward the HII Region Complex S235

Geometry of S235 resolved from SOFIA observations of ionized carbon

Velocity-resolved observations of ionized carbon in the HII-region S235 show that, although most of the radiation comes from the direction of ionized hydrogen, it has a different velocity than the ionized hydrogen. Practically the emission does not come from the same gas, but from photon-dominated dense gas behind the HII region.

The complex chemistry of hot cores in Sagittarius B2(N): Influence of cosmic-ray ionization and thermal history

This article analyzes the chemical composition of a sample of hot molecular cores detected with ALMA in the high-mass star forming region Sgr B2(N). It shows that a cosmic-ray ionization rate enhanced by a factor 50 best reproduces the observed abundance ratios of various complex organic molecules.

https://arxiv.org/abs/1906.04695

Re-exploring Molecular Complexity with ALMA (ReMoCA): Interstellar detection of urea

This article reports the interstellar detection of urea. The detection was made possible thanks to a new, sensitive spectral line survey carried out with ALMA toward the high-mass star-forming region Sgr B2(N).

https://arxiv.org/abs/1906.04614

The IRAM/GISMO two-millimeter survey in the COSMOS field

The IRAM/GISMO 2 millimeter survey in the COSMOS field provides a unique view on star formation at the time when the Universe was only two billion years old. It reveals a significant population of extreme galaxies. Compared to the Milky-Way, they are about three times more massive, and form about 1000 times more stars per year. The sheer existence of these galaxies, soon after the Big-Bang, challenges current galaxy formation models.

Radio continuum size evolution of star-forming galaxies over 0.35 < z < 2.25

We measure for the first time the overall extent within which stars in distant galaxies were born. At all cosmic epochs, star formation in massive galaxies preferentially takes place in their central region, indicating that we are witnessing the final assembly of their stellar bulges. Few galaxies have a more compact star-forming extent, and all of them produce stars at a much higher rate than the average. This suggests a different mechanism triggering their star formation activities, such as the merger of two gas-rich disks.

First direct detection of an exoplanet by optical interferometry Astrometry and K-band spectroscopy of HR 8799 e

To date, infrared interferometry at best achieved contrast ratios of a few times 10−4 on bright targets. GRAVITY, with its dual-field mode, is now capable of high contrast observations, enabling the direct observation of exoplanets. We demonstrate the technique on HR 8799, a young planetary system composed of four known giant exoplanets.

https://doi.org/10.1051/0004-6361/201935253