Search Publications
Strongly magnetized accretion in two ultracompact binary systems
Zurek, David R.; Maccarone, Thomas J.; Kupfer, Thomas +5 more
We present the discoveries of two of AM CVn systems, Gaia14aae and SDSS J080449.49+161624.8, which show X-ray pulsations at their orbital periods, indicative of magnetically collimated accretion. Both also show indications of higher rates of mass transfer relative to the expectations from binary evolution driven purely by gravitational radiation, …
Euclid preparation: XLIX. Selecting active galactic nuclei using observed colours
Prandoni, I.; Cimatti, A.; Rodighiero, G. +245 more
The Euclid space mission will cover over 14 000 deg2 with two optical and near-infrared spectro-photometric instruments, and is expected to detect around ten million active galactic nuclei (AGN). This unique data set will make a considerable impact on our understanding of galaxy evolution in general, and AGN in particular. For this work…
Moderate D/H ratios in methane ice on Eris and Makemake as evidence of hydrothermal or metamorphic processes in their interiors: Geochemical analysis
Grundy, William M.; Lunine, Jonathan I.; Glein, Christopher R. +7 more
Dwarf planets Eris and Makemake have surfaces bearing methane ice of unknown origin. This ice can provide important insights into the origin and evolution of volatiles in the outer solar system. Deuterium/hydrogen (D/H) ratios were recently determined from James Webb Space Telescope (JWST) observations of Eris and Makemake (Grundy et al., 2024b), …
iSLAT: the Interactive Spectral-line Analysis Tool for JWST and Beyond
Banzatti, Andrea; Bruderer, Simon; Jellison, Evan G. +1 more
We present the Interactive Spectral-Line Analysis Tool (iSLAT), a python-based graphical tool that allows users to interactively explore, inspect, and fit line emission observed in molecular spectra. iSLAT adopts a simple slab model in LTE that simulates emission spectra with a small set of parameters (temperature, emitting area, column density, a…
Tomographic Imaging of the Sagittarius Spiral Arm's Magnetic Field Structure
Bastien, Pierre; Coudé, Simon; Hasegawa, Tetsuo +16 more
The Galactic global magnetic field is thought to play a vital role in shaping Galactic structures such as spiral arms and giant molecular clouds. However, our knowledge of magnetic field structures in the Galactic plane at different distances is limited, as measurements used to map the magnetic field are the integrated effect along the line of sig…
From Active Stars to Black Holes: A Discovery Tool for Galactic X-Ray Sources
Rodriguez, Antonio C.
Galactic X-ray sources are diverse, ranging from active M dwarfs to compact object binaries, and everything in between. The X-ray landscape of today is rich, with point source catalogs such as those from XMM-Newton, Chandra, and Swift, each with ≳105 sources and growing. Furthermore, X-ray astronomy is on the verge of being transformed …
Investigating the Drivers of Electron Temperature Variations in H II Regions with Keck-KCWI and VLT-MUSE
Sandstrom, Karin M.; Glover, Simon C. O.; Klessen, Ralf S. +12 more
H II region electron temperatures are a critical ingredient in metallicity determinations, and recent observations have revealed systematic variations in the temperatures measured using different ions. We present electron temperatures (T e ) measured using the optical auroral lines ([N II]λ5756, [O II]λ λ7320, 7330, [S II]λ λ4069, 4076…
Kepler main-sequence solar-like stars: surface rotation and magnetic-activity evolution
García, Rafael A.; Breton, Sylvain N.; Mathur, Savita +4 more
While the mission's primary goal was focused on exoplanet detection and characterization, Kepler made and continues to make extraordinary advances in stellar physics. Stellar rotation and magnetic activity are no exceptions. Kepler allowed for these properties to be determined for tens of thousands of stars from the main sequence up to the red gia…
The cool brown dwarf Gliese 229 B is a close binary
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +76 more
Owing to their similarities with giant exoplanets, brown dwarf companions of stars provide insights into the fundamental processes of planet formation and evolution. From their orbits, several brown dwarf companions are found to be more massive than theoretical predictions given their luminosities and the ages of their host stars1–3. Ei…
Constraints on supermassive black hole binaries from JWST and NANOGrav
Loeb, Abraham; Padmanabhan, Hamsa
We use the recent statistics of dual active galactic nuclei (AGN) in the James Webb Space Telescope (JWST) data at z ∼ 3.4 to address two aspects of the feedback and evolution scenarios of supermassive black hole binaries. We find that the JWST data provide evidence for the members of a binary BH being `lit' at the same time, rather than independe…