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Related papers: Abundant ammonium hydrosulphide embedded in cometa…

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Sulphur-bearing species are detected in various environments within Galactic star-forming regions and are particularly abundant in the gas phase of outflows and shocks, and photo-dissociation regions. In this work, we aim to investigate the…

Nitrogen is the fifth most abundant element in the Universe, yet the gas-phase chemistry of N-bearing species remains poorly understood. Nitrogen hydrides are key molecules of nitrogen chemistry. Their abundance ratios place strong…

Nitrogen chemistry in protoplanetary disks and the freeze-out on dust particles is key to understand the formation of nitrogen bearing species in early solar system analogs. So far, ammonia has not been detected beyond the snowline in…

This paper is the fourth in a series whose purpose is to study the interstellar abundances of sulfur, chlorine, and argon in the Galaxy using a sample of 86 planetary nebulae. Here we present new high-quality spectrophotometric observations…

Astrophysics · Physics 2009-11-07 K. B. Kwitter , R. B. C. Henry , J. B. Milingo

The present survey represents a continuation of our study of high mass star forming regions in the lines of deuterated molecules, the first results of which were published in Trofimova et al. (2020). This paper presents the results of…

Astrophysics of Galaxies · Physics 2024-09-17 E. Trofimova , I. Zinchenko , P. Zemlyanukha , M. Thomasson

Sulfur abundances derived from optical emission line measurements and ionization correction factors in planetary nebulae are systematically lower than expected for the objects' metallicities. We have carefully considered a large range of…

Astrophysics of Galaxies · Physics 2015-06-04 R. B. C. Henry , A. Speck , A. I. Karakas , G. J. Ferland , M. Maguire

The surprising discovery by the Rosetta spacecraft of molecular oxygen (O$_2$) in the coma of comet 67P/Churyumov-Gerasimenko (Bieler et al. 2015) challenged our understanding of the inventory of this volatile species on and inside bodies…

Earth and Planetary Astrophysics · Physics 2017-08-02 J. A. Kammer , S. A. Stern , G. R. Gladstone , L. A. Young , C. B. Olkin , A. Steffl , H. A. Weaver , K. Ennico

The Alice ultraviolet spectrograph on board the \textit{Rosetta} orbiter provided the first near-nucleus ultraviolet observations of a cometary coma from arrival at comet 67P/Churyumov-Gerasimenko in 2014 August through 2016 September. The…

The presence of NH$_3$-bearing components on icy planetary bodies has important implications for their geology and potential habitability. Here, I report the detection of a characteristic NH$_3$ absorption feature at 2.20 $\pm$ 0.02 $\mu$m…

Earth and Planetary Astrophysics · Physics 2025-10-06 A. Emran

Through a survey of (sub-)millimetre emission lines of various sulphur-bearing molecules, we aim to determine which molecules are the primary carriers of sulphur in different types of AGB stars. In this paper, the first in a series, we…

Solar and Stellar Astrophysics · Physics 2017-10-25 T. Danilovich , M. Van de Sande , E. De Beck , L. Decin , H. Olofsson , S. Ramstedt , T. J. Millar

We present aluminium abundances for a sample of about 100 red giant stars in each of the Galactic globular clusters 47 Tuc (NGC 104) and M 4 (NGC 6121). We have derived homogeneous abundances from intermediate-resolution FLAMES/GIRAFFE…

Astrophysics of Galaxies · Physics 2015-06-12 Eugenio Carretta , Raffaele Gratton , Angela Bragaglia , Valentina D'Orazi , Sara Lucatello

As the closest transiting hot Jupiter to Earth, HD 189733b has been the benchmark planet for atmospheric characterization. It has also been the anchor point for much of our theoretical understanding of exoplanet atmospheres from…

The ammonia (J,K) = (1,1), (2,2), (3,3), and (4,4) transitions at 23.7 -- 24.1 GHz region were searched for in a nearby galaxy Maffei 2 to study relation between molecular abundances and physical conditions in galaxies. The (1,1), (2,2),…

Astrophysics · Physics 2015-06-24 Shuro Takano , Naomasa Nakai , Kentarou Kawaguchi , Toshiaki Takano

Evolved stars are primary sources for the formation of polycyclic aromatic hydrocarbons (PAHs) and dust grains. Their circumstellar chemistry is usually designated as either oxygen-rich or carbon-rich, although dual-dust chemistry objects,…

Solar and Stellar Astrophysics · Physics 2015-12-23 N. L. J. Cox , P. Pilleri , O. Berne , J. Cernicharo , C. Joblin

High-resolution spectra of six core helium-burning `clump' stars and three giants in the open cluster M 67 have been obtained with the SOFIN spectrograph on the Nordic Optical Telescope to investigate abundances of up to 25 chemical…

Astrophysics · Physics 2007-05-23 G. Tautvaisiene , B. Edvardsson , I. Tuominen , I. Ilyin

Ammonia (NH3) in a terrestrial planet atmosphere is generally a good biosignature gas, primarily because terrestrial planets have no significant known abiotic NH3 source. The conditions required for NH3 to accumulate in the atmosphere are,…

Earth and Planetary Astrophysics · Physics 2022-02-02 Jingcheng Huang , Sara Seager , Janusz J. Petkowski , Sukrit Ranjan , Zhuchang Zhan

In cold, dense astrophysical environments dust grains are mixed with molecular ices. Chemistry in those dust/ice mixtures is determined by diffusion and reaction of molecules and radicals. However, investigations of diffusion of…

Astrophysics of Galaxies · Physics 2025-09-17 Alexey Potapov , Kilian Pollok , Falko Langenhorst , Martin McCoustra , Robin T. Garrod

The Rosetta space probe accompanied comet 67P/Churyumov-Gerasimenko for more than two years, obtaining an unprecedented amount of unique data of the comet nucleus and inner coma. This work focuses identifying the source regions of faint…

This paper presents the chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Aluminium and Lithium abundances were derived through spectral…

Solar and Stellar Astrophysics · Physics 2022-02-09 J. Schiappacasse-Ulloa , S. Lucatello , M. J. Rain , A. Pietrinferni

We have obtained new NASA IRTF SpeX spectra of the HR 4796A debris ring system. We find a unique red excess flux that extends out to ~9 um in Spitzer IRS spectra, where thermal emission from cold, ~100K dust from the system's ring at ~75 AU…

Earth and Planetary Astrophysics · Physics 2017-10-18 Carey M. Lisse , Mike L. Sitko , Massimo Marengo , Ron J. Vervack , Yanga R. Fernandez , Tushar Mittal , Christine H. Chen