Search Publications

Implementation of disequilibrium chemistry to spectral retrieval code ARCiS and application to 16 exoplanet transmission spectra. Indication of disequilibrium chemistry for HD 209458b and WASP-39b
DOI: 10.1051/0004-6361/202141548 Bibcode: 2021A&A...656A..90K

Min, Michiel; Kawashima, Yui

Context. The retrieval approach is currently a standard method for deriving atmospheric properties from observed spectra of exoplanets. However, the approach ignores disequilibrium chemistry in most current retrieval codes, which can lead to a misinterpretation of the metallicity or elemental abundance ratios of the atmosphere.
Aims: We have …

2021 Astronomy and Astrophysics
eHST 39
Physical properties of the ambient medium and of dense cores in the Perseus star-forming region derived from Herschel Gould Belt Survey observations
DOI: 10.1051/0004-6361/201936534 Bibcode: 2021A&A...645A..55P

André, Ph.; Arzoumanian, D.; Könyves, V. +20 more

The complex of star-forming regions in Perseus is one of the most studied due to its proximity (about 300 pc). In addition, its regions show variation in star-formation activity and age, with formation of low-mass and intermediate-mass stars. In this paper, we present analyses of images taken with the Herschel ESA satellite from 70 µm to 500…

2021 Astronomy and Astrophysics
Gaia Herschel 39
Compton-thick AGN in the NuSTAR Era VI: The Observed Compton-thick Fraction in the Local Universe
DOI: 10.3847/1538-4357/ac1c73 Bibcode: 2021ApJ...922..252T

Vignali, C.; Gilli, R.; Comastri, A. +11 more

We present the analysis of simultaneous Nuclear Spectroscopic Telescope Array (NuSTAR) and XMM-Newton data of eight Compton-thick active galactic nuclei (CT-AGN) candidates selected in the Swift-BAT 100 month catalog. This work is part of an ongoing effort to find and characterize all CT-AGN in the Local (z ≤ 0.05) Universe. We used two physically…

2021 The Astrophysical Journal
XMM-Newton 39
The Hawaii Infrared Parallax Program. V. New T-dwarf Members and Candidate Members of Nearby Young Moving Groups
DOI: 10.3847/1538-4357/abe3fa Bibcode: 2021ApJ...911....7Z

Siverd, Robert J.; Dupuy, Trent J.; Liu, Michael C. +2 more

We present a search for new planetary-mass members of nearby young moving groups (YMGs) using astrometry for 694 T and Y dwarfs, including 447 objects with parallaxes, mostly produced by recent large parallax programs from UKIRT and Spitzer. Using the BANYAN Σ and LACEwING algorithms, we identify 30 new candidate YMG members, with spectral types o…

2021 The Astrophysical Journal
Gaia 39
Uncertain times: the redshift-time relation from cosmology and stars
DOI: 10.1093/mnras/stab1521 Bibcode: 2021MNRAS.505.2764B

Weisz, Daniel R.; Boylan-Kolchin, Michael

Planck data provide precise constraints on cosmological parameters when assuming the base ΛCDM model, including a 0.17 per cent measurement of the age of the Universe, $t_0=13.797 \pm 0.023\, {\rm Gyr}$. However, the persistence of the 'Hubble tension' calls the base ΛCDM model's completeness into question and has spurred interest in models such a…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 39
Rotation and Lithium Confirmation of a 500 pc Halo for the Open Cluster NGC 2516
DOI: 10.3847/1538-3881/ac18cd Bibcode: 2021AJ....162..197B

Winn, J. N.; Bouma, L. G.; Bakos, G. Á. +2 more

Recent analyses of the Gaia data have identified diffuse stellar populations surrounding nearby open clusters. It is important to verify that these "halos," "tails," and "strings" are of similar ages and compositions as stars in the denser part of the cluster. We present an analysis of NGC 2516 (≈150 Myr), which has a classical tidal radius of 10 …

2021 The Astronomical Journal
Gaia 39
Outflows from Super Star Clusters in the Central Starburst of NGC 253
DOI: 10.3847/1538-4357/abec84 Bibcode: 2021ApJ...912....4L

Meier, David S.; Ott, Jürgen; Lenkić, Laura +13 more

Young massive clusters play an important role in the evolution of their host galaxies, and feedback from the high-mass stars in these clusters can have profound effects on the surrounding interstellar medium. The nuclear starburst in the nearby galaxy NGC 253 at a distance of 3.5 Mpc is a key laboratory in which to study star formation in an extre…

2021 The Astrophysical Journal
eHST 39
Observational Signature of Tightly Wound Spirals Driven by Buoyancy Resonances in Protoplanetary Disks
DOI: 10.3847/1538-4357/abe45e Bibcode: 2021ApJ...912...56B

Bae, Jaehan; Teague, Richard; Zhu, Zhaohuan

Besides the spirals induced by the Lindblad resonances, planets can generate a family of tightly wound spirals through buoyancy resonances. The excitation of buoyancy resonances depends on the thermal relaxation timescale of the gas. By computing timescales of various processes associated with thermal relaxation, namely, radiation, diffusion, and …

2021 The Astrophysical Journal
Gaia 39
The properties of polycyclic aromatic hydrocarbons in galaxies: constraints on PAH sizes, charge and radiation fields
DOI: 10.1093/mnras/stab959 Bibcode: 2021MNRAS.504.5287R

Rigopoulou, D.; Pereira-Santaella, M.; Alonso-Herrero, A. +7 more

Based on theoretical spectra computed using Density Functional Theory we study the properties of polycyclic aromatic hydrocarbons (PAH). In particular using bin-average spectra of PAH molecules with varying number of carbons we investigate how the intensity of the mid-infrared emission bands, 3.3, 6.2, 7.7, and 11.3 $\mu$m, respond to changes in t…

2021 Monthly Notices of the Royal Astronomical Society
ISO 39
A Population of Heavily Reddened, Optically Missed Novae from Palomar Gattini-IR: Constraints on the Galactic Nova Rate
DOI: 10.3847/1538-4357/abeb75 Bibcode: 2021ApJ...912...19D

Soria, Roberto; Tinyanont, Samaporn; De, Kishalay +25 more

The nova rate in the Milky Way remains largely uncertain, despite its vital importance in constraining models of Galactic chemical evolution as well as understanding progenitor channels for Type Ia supernovae. The rate has been previously estimated to be in the range of ≈10-300 yr-1, either based on extrapolations from a handful of very…

2021 The Astrophysical Journal
Gaia 39