Search Publications
Surface localization of gas sources on comet 67P/Churyumov-Gerasimenko based on DFMS/COPS data
Altwegg, Kathrin; Rubin, Martin; Läuter, Matthias +1 more
We reconstruct the temporal evolution of the source distribution for the four major gas species H2O, CO2, CO, and O2 on the surface of comet 67P/Churyumov-Gerasimenko during its 2015 apparition. The analysis applies an inverse coma model and fits to data between 2014 August 6 and 2016 September 5 measured with the …
Fundamental parameter accuracy of DA and DB white dwarfs in Gaia Data Release 2
Tremblay, P. -E.; Hollands, M. A.; Cunningham, T. +2 more
We report on a comparison of spectroscopic analyses for hydrogen (DA) and helium atmosphere (DB) white dwarfs with Gaia Data Release 2 (DR2) parallaxes and photometry. We assume a reddening law and a mass-radius relation to connect the effective temperatures (Teff) and surface gravities (log g) to masses and radii. This allows the compa…
The CARMENES search for exoplanets around M dwarfs. Photospheric parameters of target stars from high-resolution spectroscopy. II. Simultaneous multiwavelength range modeling of activity insensitive lines
Schmitt, J. H. M. M.; Nagel, E.; Amado, P. J. +25 more
We present precise photospheric parameters of 282 M dwarfs determined from fitting the most recent version of PHOENIX models to high-resolution CARMENES spectra in the visible (0.52-0.96 µm) and NIR wavelength range (0.96-1.71 µm). With its aim to search for habitable planets around M dwarfs, several planets of different masses have be…
The Apache Point Observatory Catalog of Optical Diffuse Interstellar Bands
Zhao, Gang; York, Donald G.; Welty, Daniel E. +7 more
Aiming for a new and more comprehensive DIB catalog between 4000 and 9000 Å, we revisited the Atlas Catalog based on the observations of HD 183143 and HD 204827. Twenty-five medium to highly reddened sight lines were selected, sampling a variety of spectral types of the background star and the interstellar environments. The median signal-to-noise …
AIMS - a new tool for stellar parameter determinations using asteroseismic constraints
Chaplin, William J.; Davies, Guy R.; Campante, Tiago L. +12 more
A key aspect in the determination of stellar properties is the comparison of observational constraints with predictions from stellar models. Asteroseismic Inference on a Massive Scale (AIMS) is an open source code that uses Bayesian statistics and a Markov Chain Monte Carlo approach to find a representative set of models that reproduce a given set…
The ultra-diffuse galaxy NGC 1052-DF2 with MUSE. II. The population of DF2: stars, clusters, and planetary nebulae
Emsellem, Eric; Müller, Oliver; Peng, Eric W. +13 more
NGC 1052-DF2, an ultra-diffuse galaxy (UDG), has been the subject of intense debate. Its alleged absence of dark matter, and the brightness and number excess of its globular clusters (GCs) at an initially assumed distance of 20 Mpc suggest a new formation channel for UDGs. We present the first systematic spectroscopic analysis of the stellar body …
The Massive and Distant Clusters of WISE Survey. I. Survey Overview and a Catalog of >2000 Galaxy Clusters at z ≃ 1
Chambers, Kenneth C.; Magnier, Eugene; Wright, Edward L. +23 more
We present the Massive and Distant Clusters of WISE Survey (MaDCoWS), a search for galaxy clusters at 0.7 ≲ z ≲ 1.5 based upon data from the Wide-field Infrared Survey Explorer (WISE) mission. MaDCoWS is the first cluster survey capable of discovering massive clusters at these redshifts over the full extragalactic sky. The search is divided into t…
The effect of stellar-mass black holes on the central kinematics of ω Cen: a cautionary tale for IMBH interpretations
Hénault-Brunet, Vincent; Gieles, Mark; Zocchi, Alice
The search for intermediate-mass black holes (IMBHs) in the centre of globular clusters is often based on the observation of a central cusp in the surface brightness profile and a rise towards the centre in the velocity dispersion profiles. Similar signatures, however, could result from other effects, that need to be taken into account in order to…
Open clusters in APOGEE and GALAH. Combining Gaia and ground-based spectroscopic surveys
Jordi, C.; Casamiquela, L.; Cantat-Gaudin, T. +7 more
Context. Open clusters are ideal laboratories to investigate a variety of astrophysical topics, from the properties of the Galactic disc to stellar-evolution models. Knowing their metallicity and possibly detailed chemical abundances is therefore important. However, the number of systems with chemical abundances determined from high-resolution spe…
TESS Delivers Its First Earth-sized Planet and a Warm Sub-Neptune
Butler, R. Paul; Vanderburg, Andrew; Latham, David W. +48 more
The future of exoplanet science is bright, as Transiting Exoplanet Survey Satellite (TESS) once again demonstrates with the discovery of its longest-period confirmed planet to date. We hereby present HD 21749b (TOI 186.01), a sub-Neptune in a 36 day orbit around a bright (V = 8.1) nearby (16 pc) K4.5 dwarf. TESS measures HD 21749b to be {2.61}