Search Publications

12C/13C ratio and CNO abundances in the classical very old metal-poor dwarf HD 140283
DOI: 10.1051/0004-6361/202141741 Bibcode: 2021A&A...652A..97S

Spite, M.; Barbuy, B.; Spite, F.

Context. The isotope abundances provide powerful diagnostics of the chemical enrichment in our Galaxy. The star HD 140283 is one of the best-studied very metal-poor dwarf stars. It is very old, and the chemical abundance in this star is a good witness of the chemical composition of the matter in the early Galaxy.
Aims: The aim of this work is…

2021 Astronomy and Astrophysics
Gaia 9
Multifrequency high spectral resolution observations of HCN toward the circumstellar envelope of Y Canum Venaticorum
DOI: 10.1051/0004-6361/202040082 Bibcode: 2021A&A...651A...8F

Santander-García, M.; Cernicharo, J.; Greathouse, T. K. +7 more

High spectral resolution observations toward the low mass-loss rate C-rich, J-type asymptotic giant branch (AGB) star Y CVn were carried out at 7.5, 13.1, and 14.0 µm with the Echelon-cross-echelle Spectrograph mounted on the Stratospheric Observatory for Infrared Astronomy and the Texas Echelon-cross-echelle Spectrograph on the Infrared Tel…

2021 Astronomy and Astrophysics
AKARI Gaia ISO 9
ALMA observations of the early stages of substellar formation in the Lupus 1 and 3 molecular clouds
DOI: 10.1051/0004-6361/202039419 Bibcode: 2021A&A...646A..10S

Hales, A.; de Gregorio-Monsalvo, I.; Bayo, A. +10 more

Context. The dominant mechanism leading to the formation of brown dwarfs (BDs) remains uncertain. While the census of Class II analogs in the substellar domain continues to grow, the most direct keys to formation, which are obtained from younger objects (pre-BD cores and proto-BDs), are limited by the very low number statistics available.
Aim…

2021 Astronomy and Astrophysics
Gaia Herschel 9
Multi-wavelength VLTI study of the puffed-up inner rim of a circumbinary disc
DOI: 10.1051/0004-6361/202141154 Bibcode: 2021A&A...650L..13C

Min, M.; Van Winckel, H.; Kamath, D. +3 more

Context. The presence of stable, compact circumbinary discs of gas and dust around post-asymptotic giant branch (post-AGB) binary systems has been well established. We focus on one such system, IRAS 08544−4431.
Aims: We present an interferometric multi-wavelength analysis of the circumstellar environment of IRAS 08544−4431. The aim is to cons…

2021 Astronomy and Astrophysics
Gaia 9
A Multi-instrument Study of the 2018 Hard-state-only Outburst of H1743-322
DOI: 10.3847/1538-4357/abfaa5 Bibcode: 2021ApJ...914...93S

Stiele, H.; Kong, A. K. H.

Distinct changes of the spectral and variability properties observed in black hole transients during a bright outburst deliver insight into the evolution of the accretion flow and accretion geometry. We investigated NICER and Swift monitoring observations of H 1743-322 during its 2018 outburst as well as NuSTAR and XMM-Newton data. The observed ha…

2021 The Astrophysical Journal
XMM-Newton 9
The Encounter of the Parker Solar Probe and a Comet-like Object Near the Sun: Model Predictions and Measurements
DOI: 10.3847/1538-4357/abdf4a Bibcode: 2021ApJ...910....7H

Zong, Qiugang; He, Jiansen; Ip, Wing-Huen +15 more

The Parker Solar Probe (PSP) aims to explore the nascent solar wind close to the Sun. Meanwhile, PSP is also expected to encounter small objects like comets and asteroids. In this work, we survey the ephemerides to find the chance of a recent encounter and then model the interaction between released dusty plasmas and solar wind plasmas. On 2019 Se…

2021 The Astrophysical Journal
SOHO 9
Winds in the Lower Cloud Level on the Nightside of Venus from VIRTIS-M (Venus Express) 1.74 µm Images
DOI: 10.3390/atmos12020186 Bibcode: 2021Atmos..12..186G

Khatuntsev, Igor V.; Patsaeva, Marina V.; Zasova, Ludmila V. +2 more

2021 Atmosphere
VenusExpress 9
ALMA Observation of the Protoplanetary Disk around WW Cha: Faint Double-peaked Ring and Asymmetric Structure
DOI: 10.3847/1538-4357/abdfc5 Bibcode: 2021ApJ...909..212K

Dong, Ruobing; Kataoka, Akimasa; Takami, Michihiro +13 more

We present Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 observations of dust continuum emission of the disk around WW Cha. The dust continuum image shows a smooth disk structure with a faint (low-contrast) dust ring, extending from ∼40 au to ∼70 au, not accompanied by any gap. We constructed the simple model to fit the visibility of …

2021 The Astrophysical Journal
Gaia 9
Spatially-resolved stellar population properties of the M51-NGC 5195 system from multi-wavelength photometric data
DOI: 10.1088/1674-4527/21/1/6 Bibcode: 2021RAA....21....6W

Kong, Xu; Zou, Hu; Lin, Lin +5 more

Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared, we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models. The observed infrared excess (IRX) is used to constrain dust extinction. Stellar mass is also inferred f…

2021 Research in Astronomy and Astrophysics
Gaia Herschel XMM-Newton 9
A Search for Cloud Cores Affected by Shocked Carbon Chain Chemistry in L1251
DOI: 10.3847/1538-4357/abee73 Bibcode: 2021ApJ...912..148L

Kim, Kee-Tae; Xu, Y.; Li, D. +26 more

We searched for shocked carbon chain chemistry (SCCC) sources with C3S abundances surpassing those of HC5N toward the dark cloud L1251, using the Effelsberg telescope at the K band (18-26 GHz). L1251-1 and L1251-3 are identified as the most promising SCCC sources. The two sources harbor young stellar objects. We conducted map…

2021 The Astrophysical Journal
Herschel 9