Related papers: A lambda 3mm and 1mm line survey toward the yellow…
We investigate the molecular gas properties of the deeply obscured luminous infrared galaxy NGC 4418. We address the excitation of the complex molecule HC3N to determine whether its unusually luminous emission is related to the nature of…
The evolution of massive stars surviving the red supergiant (RSG) stage remains unexplored due to the rarity of such objects. The yellow hypergiants (YHGs) appear to be the warm counterparts of post-RSG classes located near the…
We present molecular line observations made with the IRAM 30-m telescope of the immediate surroundings of a sample of 11 candidate high-mass protostars. These observations are part of an effort to clarify the evolutionary status of a set of…
We determine the spectroscopic properties of ~1000 ostensibly star-forming galaxies at redshifts (z=4-10) using prism spectroscopy from JWST/NIRSpec. With rest-wavelength coverage between Lya and [S II] in the optical, we stack spectra as a…
The 12CO J=4-3 to J=13-12 lines of the interstellar medium from nearby galaxies, newly observable with the Herschel SPIRE Fourier Transform Spectrometer (FTS), offer an opportunity to study warmer, more luminous molecular gas than that…
We present NLTE abundances of CNO for a sample of four O9 stars in the Galaxy, together with new determinations of their stellar parameters, $T_{\rm eff}$, $\log g$, $\epsilon$(He) and microturbulence. These new analyses take into account…
Two new ON supergiant spectra (bringing the total known to seven) and one new ONn giant (total of this class now eight) are presented; they have been discovered by the Galactic O-Star Spectroscopic Survey. These rare objects represent…
(Abridged) We have obtained new spectrophotometric data for 28 HII regions in the spiral galaxy NGC 300, a member of the nearby Sculptor Group. The detection of auroral lines, including [OIII]4363, [SIII]6312 and [NII]5755, has allowed us…
We report the detection of absorption lines by the reactive ions OH+, H2O+ and H3O+ along the line of sight to the submillimeter continuum source G10.6$-$0.4 (W31C). We used the Herschel HIFI instrument in dual beam switch mode to observe…
Red Midcourse Space Experiment (MSX) Sources (RMSs) are regarded as excellent candidates of massive starforming regions. In order to characterize the chemical properties of massive star formation, we made a systematic study of 87 RMSs in…
Recent supernova and transient surveys have revealed an increasing number of non-terminal stellar eruptions. Though the progenitor class of these eruptions includes the most luminous stars, little is known of the pre-supernova mechanics of…
A CO(1-0) on-source spectrum of the well-known carbon star IRC+10216 taken with the IRAM 30m telescope in June 1996 shows excess emission between -18.3 and -14.3 km/s at the red wing of the underlying profile. The excess emission is…
The outer Galaxy is characterized by a lower metallicity than regions near the Sun, suggesting differences in the formation and survival of molecules in star-forming regions. To understand chemical evolution across the Milky Way, deriving…
We perform a complete census of molecular ions with an abundance larger than 1e-10 in the protostellar shock L1157-B1 by means of an unbiased high-sensitivity survey obtained with the IRAM-30m and Herschel/HIFI. By means of an LVG radiative…
Urea, NH2C(O)NH2, is a molecule of great importance in organic chemistry and biology. Two searches for urea in the interstellar medium were reported in the past, but neither were conclusive. We want to take advantage of the increased…
Massive stars rotate faster, on average, than lower mass stars. Stellar rotation triggers hydrodynamical instabilities which transport angular momentum and chemical species from the core to the surface. Models of high-mass stars that…
Infrared emission from the dust shell around IRC+10216 is analysed in detail, employing a self-consistent model for radiatively driven winds around late-type stars that couples the equations of motion and radiative transfer in the dust. The…
We present optical and near-IR imaging and spectroscopy of SGAS J105039.6$+$001730, a strongly lensed galaxy at z $=$ 3.6252 magnified by $>$30$\times$, and derive its physical properties. We measure a stellar mass of…
Massive stars form deeply embedded in dense molecular gas, which they stir and heat up and ionize. During an early phase, the ionization is confined to hypercompact HII regions, and the stellar radiation is entirely absorbed by dust, giving…
We present the results of our ALMA observations of eleven (ultra)luminous infrared galaxies ((U)LIRGs) at J=4-3 of HCN, HCO+, HNC and J=3-2 of HNC. This is an extension of our previously published HCN and HCO+ J=3-2 observations to multiple…