Search Publications
Missions
Journals
Publication Years
Local stellar formation history from the 40 pc white dwarf sample
Tremblay, P. -E.; McCleery, J.; Cukanovaite, E. +4 more
We derive the local stellar formation history from the Gaia-defined 40 pc white dwarf sample. This is currently the largest volume-complete sample of white dwarfs for which spectroscopy is available, allowing for classification of the chemical abundances at the photosphere, and subsequently accurate determination of the atmospheric parameters. We …
Spectroscopic Time-series Performance of JWST/NIRSpec from Commissioning Observations
Nikolov, Nikolay; Sing, David K.; Böker, Torsten +22 more
We report on James Webb Space Telescope (JWST) commissioning observations of the transiting exoplanet HAT-P-14 b, obtained using the Bright Object Time Series (BOTS) mode of the NIRSpec instrument with the G395H/F290LP grating/filter combination (3-5 µm). While the data were used primarily to verify that the NIRSpec BOTS mode is working as e…
The impact of early massive mergers on the chemical evolution of Milky Way-like galaxies: insights from NIHAO-UHD simulations
Buck, Tobias; Minchev, Ivan; Macciò, Andrea V. +3 more
Recent observations of the Milky Way (MW) found an unexpected steepening of the star-forming gas metallicity gradient around the time of the Gaia-Sausage-Enceladus (GSE) merger event. Here, we investigate the influence of early (tmerger ≲ 5 Gyr) massive ($M_{\rm {gas}}^{\rm {merger}}/M_{\rm {gas}}^{\rm {main}}(t_{\rm {merger}})\gtrsim 1…
CEERS MIRI Imaging: Data Reduction and Quality Assessment
Yung, L. Y. Aaron; Kartaltepe, J. S.; Dickinson, M. +35 more
The Cosmic Evolution Early Release Science Survey (CEERS), targeting the Extended Groth Strip extragalactic field, is one of the James Webb Space Telescope Director's Discretionary Early Release Science programs. To date, all observations have been executed and include NIRCam/MIRI imaging and NIRSpec/NIRCam spectroscopic exposures. Here we discuss…
A massive helium star with a sufficiently strong magnetic field to form a magnetar
Wade, Gregg A.; Toonen, Silvia; Sana, Hugues +13 more
Magnetars are highly magnetized neutron stars, the formation mechanism of which is unknown. Hot helium-rich stars with spectra dominated by emission lines are known as Wolf-Rayet stars. We observed the binary system HD 45166 using spectropolarimetry and reanalyzed its orbit using archival data. We found that the system contains a Wolf-Rayet star w…
A state-of-the-art strong-lensing model of MACS J0416.1−2403 with the largest sample of spectroscopic multiple images
Grillo, C.; Rosati, P.; Vanzella, E. +9 more
The combination of multi-band imaging from the Hubble Space Telescope with Multi-Unit Spectroscopic Explorer integral field spectroscopy, obtained at the Very Large Telescope, has recently driven remarkable progress in strong-lensing (SL) modeling of galaxy clusters. From a few tens of multiple images with photometric redshifts per cluster, a new …
Clues on the presence and segregation of very massive stars in the Sunburst Lyman-continuum cluster at z = 2.37
Schaerer, D.; Martins, F.; Marques-Chaves, R. +15 more
We report the identification of very massive stars (VMS; mass > 100 M⊙) that may be segregated in the center of the young massive star cluster at z = 2.37 hosted in the lensed galaxy called Sunburst galaxy. This result is based on two pieces of evidence: (1) VLT/MUSE spectra of several multiple images of the same star cluster show ke…
A Reanalysis of the Isolated Black Hole Candidate OGLE-2011-BLG-0462/MOA-2011-BLG-191
Lu, Jessica R.; Lam, Casey Y.
There are expected to be ~108 isolated black holes (BHs) in the Milky Way. OGLE-2011-BLG-0462/MOA-2011-BLG-191 (OB110462) is the only such BH with a mass measurement to date. However, its mass is disputed: Lam et al. measured a lower mass of 1.6-4.4 M ⊙, while Sahu et al. and Mróz et al. measured a higher mass of 5.8-8.7 M
Gaia Data Release 3. Cross-match of Gaia sources with variable objects from the literature
Gavras, Panagiotis; Ábrahám, Péter; Kóspál, Ágnes +22 more
Context. In current astronomical surveys with ever-increasing data volumes, automated methods are essential. Objects of known classes from the literature are necessary to train supervised machine-learning algorithms and to verify and validate their results.
Aims: The primary goal of this work is to provide a comprehensive data set of known va…
The ALMA REBELS Survey: the first infrared luminosity function measurement at z ∼ 7
Inami, H.; Schneider, R.; Oesch, P. A. +18 more
We present the first observational infrared luminosity function (IRLF) measurement in the Epoch of Reionization (EoR) based on a ultraviolet (UV)-selected galaxy sample with the Atacama Large Millimeter Array (ALMA) spectroscopic observations. Our analysis is based on the ALMA large program Reionization Era Bright Emission Line Survey (REBELS), wh…