Search Publications
Age dissection of the Milky Way discs: Red giants in the Kepler field
Khan, S.; Valentini, M.; Chiappini, C. +16 more
Ensemble studies of red-giant stars with exquisite asteroseismic (Kepler), spectroscopic (APOGEE), and astrometric (Gaia) constraints offer a novel opportunity to recast and address long-standing questions concerning the evolution of stars and of the Galaxy. Here, we infer masses and ages for nearly 5400 giants with available Kepler light curves a…
X-ray quasi-periodic eruptions from two previously quiescent galaxies
Gromadzki, M.; Salvato, M.; Buchner, J. +21 more
Quasi-periodic eruptions (QPEs) are very-high-amplitude bursts of X-ray radiation recurring every few hours and originating near the central supermassive black holes of galactic nuclei1,2. It is currently unknown what triggers these events, how long they last and how they are connected to the physical properties of the inner accretion f…
Distances to PHANGS galaxies: New tip of the red giant branch measurements and adopted distances
Van Dyk, Schuyler D.; Kruijssen, J. M. Diederik; Leroy, Adam K. +29 more
PHANGS-HST is an ultraviolet-optical imaging survey of 38 spiral galaxies within ~20 Mpc. Combined with the PHANGS-ALMA, PHANGS-MUSE surveys and other multiwavelength data, the data set will provide an unprecedented look into the connections between young stars, H II regions, and cold molecular gas in these nearby star-forming galaxies. Accurate d…
The [O III]+H β equivalent width distribution at z ≃ 7: implications for the contribution of galaxies to reionization
Charlot, Stéphane; Chevallard, Jacopo; Stark, Daniel P. +1 more
We quantify the distribution of [O III]+H β line strengths at z ≃ 7 using a sample of 20 bright ( $\mathrm{M}_{\mathrm{UV}}^{}$ ≲ -21) galaxies. We select these systems over wide-area fields (2.3 deg2 total) using a new colour-selection that precisely selects galaxies at z ≃ 6.63-6.83, a redshift range where blue Spitzer/IRAC [3.6]-[4.5…
A buyer's guide to the Hubble constant
Lahav, Ofer; Lemos, Pablo; Shah, Paul
Since the expansion of the universe was first established by Edwin Hubble and Georges Lemaître about a century ago, the Hubble constant H0 which measures its rate has been of great interest to astronomers. Besides being interesting in its own right, few properties of the universe can be deduced without it. In the last decade, a signific…
The Evolution of the IR Luminosity Function and Dust-obscured Star Formation over the Past 13 Billion Years
Kartaltepe, J. S.; Yun, M. S.; Clements, D. L. +25 more
We present the first results from the Mapping Obscuration to Reionization with ALMA (MORA) survey, the largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey to date (184 arcmin2) and the only at 2 mm to search for dusty star-forming galaxies (DSFGs). We use the 13 sources detected above 5σ to estimate…
VINTERGATAN - I. The origins of chemically, kinematically, and structurally distinct discs in a simulated Milky Way-mass galaxy
Feuillet, Diane K.; Feltzing, Sofia; Ryde, Nils +6 more
Spectroscopic surveys of the Milky Way's stars have revealed spatial, chemical, and kinematical structures that encode its history. In this work, we study their origins using a cosmological zoom simulation, VINTERGATAN, of a Milky Way-mass disc galaxy. We find that in connection to the last major merger at z ∼ 1.5, cosmological accretion leads to …
Space weather: the solar perspective: An update to Schwenn (2006)
Temmer, Manuela
The Sun, as an active star, is the driver of energetic phenomena that structure interplanetary space and affect planetary atmospheres. The effects of Space Weather on Earth and the solar system is of increasing importance as human spaceflight is preparing for lunar and Mars missions. This review is focusing on the solar perspective of the Space We…
Reconstructing the Last Major Merger of the Milky Way with the H3 Survey
Conroy, Charlie; Ting, Yuan-Sen; Cargile, Phillip A. +8 more
Several lines of evidence suggest that the Milky Way underwent a major merger at z ~ 2 with the Gaia-Sausage-Enceladus (GSE) galaxy. Here we use H3 Survey data to argue that GSE entered the Galaxy on a retrograde orbit based on a population of highly retrograde stars with chemistry similar to the largely radial GSE debris. We present the first tai…
The Hubble Constant from Infrared Surface Brightness Fluctuation Distances
Ma, Chung-Pei; Greene, Jenny E.; Blakeslee, John P. +2 more
We present a measurement of the Hubble constant H0 from surface brightness fluctuation (SBF) distances for 63 bright, mainly early-type galaxies out to 100 Mpc observed with the WFC3/IR on the Hubble Space Telescope (HST). The sample is drawn from several independent HST imaging programs using the F110W bandpass, with the majority of th…