Search Publications
Giant galaxy growing from recycled gas: ALMA maps the circumgalactic molecular medium of the Spiderweb in [C I]
Villar-Martín, M.; Dannerbauer, H.; Guillard, P. +9 more
The circumgalactic medium (CGM) of the massive Spiderweb Galaxy, a conglomerate of merging proto-cluster galaxies at z = 2.2, forms an enriched interface where feedback and recycling act on accreted gas. This is shown by observations of [C I], CO(1-0), and CO(4-3) performed with the Atacama Large Millimeter Array and Australia Telescope Compact Ar…
Chasing passive galaxies in the early Universe: a critical analysis in CANDELS GOODS-South
Elbaz, D.; Ciesla, L.; Wang, T. +12 more
We search for passive galaxies at z > 3 in the GOODS-South field, using different techniques based on photometric data, and paying attention to develop methods that are sensitive to objects that have become passive shortly before the epoch of observation. We use CANDELS HST catalogues, ultra-deep Ks data and new IRAC photometry, performing spec…
The R-Process Alliance: A Comprehensive Abundance Analysis of HD 222925, a Metal-poor Star with an Extreme R-process Enhancement of [Eu/H] = -0.14
Beers, Timothy C.; Placco, Vinicius M.; Hansen, Terese T. +4 more
We present a detailed abundance analysis of the bright (V = 9.02), metal-poor ([Fe/H] = -1.47 ± 0.08) field red horizontal-branch star HD 222925, which was observed as part of an ongoing survey by the R-Process Alliance. We calculate stellar parameters and derive abundances for 46 elements based on 901 lines examined in a high-resolution optical s…
New ultra-cool and brown dwarf candidates in Gaia DR2
Reylé, C.
Context. The second Gaia data release (Gaia DR2) contains high-precision positions, parallaxes, and proper motions for 1.3 billion sources. The resulting Hertzsprung-Russel diagram reveals fine structures throughout the mass range.
Aims: This paper aims to investigate the content of Gaia DR2 at the low-mass end and to characterize ultra-cool …
The LEECH Exoplanet Imaging Survey: Limits on Planet Occurrence Rates under Conservative Assumptions
Fortney, Jonathan J.; De Rosa, Robert J.; Weigelt, Gerd +33 more
We present the results of the largest L‧ (3.8 µm) direct imaging survey for exoplanets to date, the Large Binocular Telescope Interferometer Exozodi Exoplanet Common Hunt (LEECH). We observed 98 stars with spectral types from B to M. Cool planets emit a larger share of their flux in L‧ compared to shorter wavelengths, affording LEECH an adva…
Chemical interactions between Saturn's atmosphere and its rings
Kurth, W. S.; Mitchell, D. G.; Wahlund, J. -E. +25 more
The Pioneer and Voyager spacecraft made close-up measurements of Saturn's ionosphere and upper atmosphere in the 1970s and 1980s that suggested a chemical interaction between the rings and atmosphere. Exploring this interaction provides information on ring composition and the influence on Saturn's atmosphere from infalling material. The Cassini Io…
Characteristics of Late-phase >100 MeV Gamma-Ray Emission in Solar Eruptive Events
White, S. M.; Dennis, B. R.; Murphy, R. J. +5 more
We characterize and catalog 30 solar eruptive events observed by the Fermi Large Area Telescope (LAT) having late-phase >100 MeV γ-ray emission (LPGRE), identified 30 yr ago in what were called long-duration gamma-ray flares. We show that LPGRE is temporally and spectrally distinct from impulsive phase emission in these events. The spectra are …
BANYAN. XII. New Members of Nearby Young Associations from GAIA-Tycho Data
Faherty, Jacqueline K.; Gagné, Jonathan; Doyon, René +2 more
We present a search for stellar members of young associations within 150 pc of the Sun, based on TGAS and an updated version of the BANYAN Σ software to determine Bayesian membership probabilities that includes Gaia-2MASS color-magnitude diagrams. We identify 32 new F0-M3-type bona fide members of the 10-200 Myr old Sco-Cen, Carina, Tucana-Horolog…
The Redshift Evolution of Rest-UV Spectroscopic Properties in Lyman-break Galaxies at z ∼ 2-4
Pettini, Max; Erb, Dawn K.; Shapley, Alice E. +8 more
We present the first comprehensive evolutionary analysis of the rest-frame UV spectroscopic properties of star-forming galaxies at z ∼ 2-4. We match samples at different redshifts in UV luminosity and stellar mass, and perform systematic measurements of spectral features and stellar population modeling. By creating composite spectra grouped accord…
The Distance of the Dark Matter Deficient Galaxy NGC 1052-DF2
van Dokkum, Pieter; Romanowsky, Aaron J.; Conroy, Charlie +2 more
We recently inferred that the galaxy NGC 1052-DF2 has little or no dark matter and a rich system of unusual globular clusters. We assumed that the galaxy is a satellite of the luminous elliptical galaxy NGC 1052 at ≈20 Mpc, on the basis of its surface brightness fluctuations (SBFs) distance of 19.0 ± 1.7 Mpc, its radial velocity of ≈1800 km s…