Search Publications
JWST/MIRI Spectroscopy of the Disk of the Young Eruptive Star EX Lup in Quiescence
Banzatti, Andrea; Henning, Thomas; Bouwman, Jeroen +7 more
EX Lup is a low-mass pre-main-sequence star that occasionally shows accretion-related outbursts. Here, we present JWST/MIRI medium-resolution spectroscopy obtained for EX Lup 14 yr after its powerful outburst. EX Lup is now in quiescence and displays a Class II spectrum. We detect a forest of emission lines from molecules previously identified in …
JWST: Deuterated PAHs, PAH Nitriles, and PAH Overtone and Combination Bands. I. Program Description and First Look
Boersma, C.; Bregman, J. D.; Allamandola, L. J. +6 more
A first look is taken at the NIRSpec 1-5 µm observations from James Webb Space Telescope program 1591 that targets seven objects along the low-mass stellar life cycle with polycyclic aromatic hydrocarbon (PAH) emission. Spectra extracted from a 1.″5 radius circular aperture are explored, showing a wealth of features, including the 3 µm…
Analysing the SEDs of protoplanetary disks with machine learning
Pinte, C.; Woitke, P.; Kamp, I. +2 more
Context. The analysis of spectral energy distributions (SEDs) of protoplanetary disks to determine their physical properties is known to be highly degenerate. Hence, a full Bayesian analysis is required to obtain parameter uncertainties and degeneracies. The main challenge here is computational speed, as one proper full radiative transfer model re…
Source counts at 7.7-21 µm in CEERS field with JWST
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +8 more
Source counts - the number density of sources as a function of flux density - represent one of the fundamental metrics in observational cosmology due to their straightforward and simple nature. It is an important tool that provides information on galaxy formation and evolution. Source counting is a direct measurement. Compared to advanced analyses…
The intense production of silicates during the final AGB phases of intermediate mass stars
Dell'Agli, F.; Ventura, P.; Fabrizio, M. +7 more
Context. The formation of silicates in circumstellar envelopes of stars evolving through the asymptotic giant branch (AGB) is still highly debated given the uncertainties affecting stellar evolution modelling, the description of the dust formation process, and the capability of silicate grains to accelerate stellar outflows via radiation pressure.…
Dissecting the Mid-infrared Heart of M83 with JWST
Kumari, Nimisha; Hirschauer, Alec S.; Hernandez, Svea +10 more
We present a first look at the MRS observations of the nucleus of the nearby galaxy M83, taken with MIRI on board JWST. The observations show a rich set of emission features from the ionized gas, warm molecular gas, and dust. To begin dissecting the complex processes in this part of the galaxy, we divide the observations into four different region…
The Mid-infrared Molecular Inventory toward Orion IRc2
Drozdovskaya, Maria N.; Herbst, Eric; Acharyya, Kinsuk +8 more
We present the first high spectral resolution mid-infrared survey in the Orion BN/KL region, covering 7.2–28.3 µm. With SOFIA/EXES, we target the enigmatic source Orion IRc2. While this is in the most prolifically studied massive star-forming region, longer wavelengths and molecular emission lines dominated previous spectral surveys. The mid…
The hunt for formamide in interstellar ices. A toolkit of laboratory infrared spectra in astronomically relevant ice mixtures and comparisons to ISO, Spitzer, and JWST observations
van Dishoeck, E. F.; Rocha, W. R. M.; Slavicinska, K. +3 more
Context. Although solid-state pathways are expected to dominate the formation mechanisms of many complex organic molecules (COMs), very few COMs have been securely identified in interstellar ices, in stark contrast with the many COM detections in the gas phase. The launch of the James Webb Space Telescope (JWST) and its increase in sensitivity and…
The dusty circumstellar environment of Betelgeuse during the Great Dimming as seen by VLTI/MATISSE
Danchi, W.; Matter, A.; Lopez, B. +23 more
Context. The `Great Dimming' of the prototypical red supergiant Betelgeuse, which occurred between December 2019 and April 2020, gives us unprecedented insight into the processes occurring on the stellar surface and in the inner wind of this type of star. In particular it may bring further understanding of their dust nucleation and mass-loss proce…
Deuterated Polycyclic Aromatic Hydrocarbons in the Interstellar Medium: The Aliphatic C-D Band Strengths
Li, Aigen; Yang, X. J.
Deuterium (D) was exclusively generated in the Big Bang, and the standard Big Bang nucleosynthesis (BBN) model predicts a primordial abundance of D/H ≈ 26 parts per million (ppm). As the Galaxy evolves, D/H gradually decreases because of astration. The Galactic chemical evolution (GCE) model predicts a present-day abundance of D/H ≳ 20 ppm. Howeve…