Search Publications
Completeness of the Gaia-verse III: using hidden states to infer gaps, detection efficiencies, and the scanning law from the DR2 light curves
Everall, Andrew; Boubert, Douglas; Fraser, Jack +2 more
The completeness of the Gaia catalogues heavily depends on the status of that space telescope through time. Stars are only published with each of the astrometric, photometric, and spectroscopic data products if they are detected a minimum number of times. If there is a gap in scientific operations, a drop in the detection efficiency or Gaia deviat…
The Gaia-ESO Survey: Oxygen Abundance in the Galactic Thin and Thick Disks
Kordopatis, Georges; Bragaglia, Angela; Adibekyan, Vardan +18 more
We analyze the oxygen abundances of a stellar sample representative of the two major Galactic populations: the thin and thick disks. The aim is to investigate the differences between members of the Galactic disks and contribute to the understanding of the origin of oxygen chemical enrichment in the Galaxy. The analysis is based on the [O I] = 6300…
A hot mini-Neptune in the radius valley orbiting solar analogue HD 110113
Bouchy, F.; Deleuil, M.; Helled, R. +53 more
We report the discovery of HD 110113 b (TESS object of interest-755.01), a transiting mini-Neptune exoplanet on a 2.5-d orbit around the solar-analogue HD 110113 (Teff = 5730 K). Using TESS photometry and High Accuracy Radial velocity Planet Searcher (HARPS) radial velocities gathered by the NCORES program, we find that HD 110113 b has …
Investigation of Orbital Decay and Global Modeling of the Planet WASP-43 b
Davoudi, Fatemeh; Safari, Hossein; Baştürk, Özgür +2 more
WASP-43 b is one of the most important candidates for detecting an orbital decay. We investigate pieces of evidence for this expectation as variations in its transit timings, based on the ground and space observations. The data set includes the transit observations at the TÜBİTAK National Observatory of Turkey and Transiting Exoplanet Survey Satel…
Searching For Transiting Planets Around Halo Stars. II. Constraining the Occurrence Rate of Hot Jupiters
Li, Ting S.; Collins, Karen A.; Collins, Kevin I. +4 more
Jovian planet formation has been shown to be strongly correlated with host-star metallicity, which is thought to be a proxy for disk solids. Observationally, previous works have indicated that Jovian planets preferentially form around stars with solar and supersolar metallicities. Given these findings, it is challenging to form planets within meta…
OGLE-2018-BLG-1185b: A Low-mass Microlensing Planet Orbiting a Low-mass Dwarf
Kim, S. -L.; Lee, C. -U.; Bryden, G. +96 more
We report an analysis of the planetary microlensing event OGLE-2018-BLG-1185, which was observed by a large number of ground-based telescopes and by the Spitzer Space Telescope. The ground-based light curve indicates a low planet-host star mass ratio of q = (6.9 ± 0.2) × 10-5, which is near the peak of the wide-orbit exoplanet mass-rati…
An Asymmetric Dust Ring around a Very Low Mass Star ZZ Tau IRS
Dong, Ruobing; Hashimoto, Jun; Muto, Takayuki
We present Atacama Large Millimeter/submillimeter Array (ALMA) gas and dust observations at band 7 (339 GHz: 0.89 mm) of the protoplanetary disk around a very low mass star ZZ Tau IRS with a spatial resolution of 0"25. The 12CO J = 3 → 2 position-velocity diagram suggests a dynamical mass of ZZ Tau IRS of ∼0.1-0.3 M⊙. The dis…
Massive young stellar objects in the Local Group irregular galaxy NGC 6822 identified using machine learning
van Loon, Jacco Th; Oliveira, Joana M.; Kinson, David A.
We present a supervised machine learning methodology to classify stellar populations in the Local Group dwarf-irregular galaxy NGC 6822. Near-IR colours (J - H, H - K, and J - K), K-band magnitudes and far-IR surface brightness (at 70 and 160 $\mu$m) measured from Spitzer and Herschel images are the features used to train a Probabilistic Random Fo…
The dependence of the hierarchical distribution of star clusters on galactic environment
Grebel, Eva K.; Smith, Linda J.; Calzetti, Daniela +15 more
We use the angular two-point correlation function (TPCF) to investigate the hierarchical distribution of young star clusters in 12 local (3-18 Mpc) star-forming galaxies using star cluster catalogs obtained with the Hubble Space Telescope (HST) as part of the Treasury Program Legacy ExtraGalactic UV Survey. The sample spans a range of different mo…
Physical characterization of recently discovered globular clusters in the Sagittarius dwarf spheroidal galaxy. I. Metallicities, ages, and luminosities
Minniti, D.; Alonso-García, J.; Gómez, M. +1 more
Context. Globular clusters (GCs) are important tools for rebuilding the accretion history of a galaxy. In particular, newly discovered GCs in the Sagittarius (Sgr) dwarf galaxy can be used as probes of the accretion event onto the Milky Way (MW).
Aims: Our main aim is to characterize the GC system of the Sgr dwarf galaxy by measuring its main…