Search Publications
Misalignment of the outer disk of DK Tau and a first look at its magnetic field using spectropolarimetry
Donati, J. -F.; Vidotto, A. A.; Bouvier, J. +7 more
Context. Misalignments between a forming star's rotation axis and its outer disk axis, although not predicted by standard theories of stellar formation, have been observed in several classical T Tauri stars (cTTs). The low-mass cTTs DK Tau is suspected of being among them. In addition, it is an excellent subject to investigate the interaction betw…
Arp 220: A Post-starburst Galaxy with Little Current Star Formation outside of Its Nuclear Disks
Calzetti, Daniela; Whitmore, Bradley C.; Chandar, Rupali +8 more
The ultraluminous infrared galaxy Arp 220 is a late-stage merger with several tidal structures in the outskirts and two very compact, dusty nuclei that show evidence for extreme star formation and host at least one active galactic nucleus (AGN). New and archival high-resolution images taken by the Hubble Space Telescope provide a state-of-the-art …
TIC 219006972: a compact, coplanar quadruple star system consisting of two eclipsing binaries with an outer period of 168 d
Kostov, Veselin B.; Powell, Brian P.; Rappaport, Saul A. +12 more
We present the discovery of a new highly compact quadruple star system, TIC 219006972, consisting of two eclipsing binary stars with orbital periods of 8.3 and 13.7 d, and an outer orbital period of only 168 d. This period is a full factor of 2 shorter than the quadruple with the shortest outer period reported previously, VW LMi, where the two bin…
Investigating Europa's Radiation Environment with the Europa Clipper Radiation Monitor
McEwen, Alfred; Clark, Roger; Paranicas, Chris +23 more
We present an overview of the radiation environment monitoring program planned for the Europa Clipper mission. The harsh radiation environment of Jupiter will be measured by a dedicated Radiation Monitor (RadMon) subsystem, yielding mission accumulative Total Ionizing Dose (TID) and instantaneous electron flux measurements with a 1-Hz cadence. The…
Influence of Solar Wind Variations on the Shapes of Venus' Plasma Boundaries Based on Venus Express Observations
André, N.; Fedorov, A.; Futaana, Y. +10 more
The interaction between the solar wind and Venus creates an induced magnetosphere. The regions of the induced magnetosphere are separated by plasma boundaries, where their shapes and sizes are influenced by variations in the surrounding environment. Investigations of the boundaries and their variability can help us understand the solar wind's effe…
MOSEL Survey: JWST Reveals Major Mergers/strong Interactions Drive the Extreme Emission Lines in the Early Universe
Harshan, Anishya; Kacprzak, Glenn G.; Nanayakkara, Themiya +7 more
Extreme emission line galaxies (EELGs), where nebular emissions contribute 30%-40% of the flux in certain photometric bands, are ubiquitous in the early Universe (z > 6). We utilize deep NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) to investigate the properties of companion galaxies (projected distance <40 kpc, ∣dv…
Magnetic helicity and free magnetic energy as tools for probing eruptions in two differently evolving solar active regions
Georgoulis, M. K.; Nindos, A.; Liokati, E.
Aims: We study the role of magnetic helicity and free magnetic energy in the initiation of eruptions in two differently evolving solar active regions (ARs).
Methods: Using vector magnetograms from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory and a magnetic connectivity-based method, we calculate the instan…
Freezing in vector dark matter through magnetic dipole interactions
Krnjaic, Gordan; Rocha, Duncan; Sokolenko, Anastasia
We study a simple model of vector dark matter that couples to Standard Model particles via magnetic dipole interactions. In this scenario, the cosmological abundance arises through the freeze-in mechanism and depends on the dipole coupling, the vector mass, and the reheat temperature. To ensure cosmological metastability, the vector must be lighte…
VaTEST I: validation of sub-Saturn exoplanet TOI-181b in narrow orbit from its host star
Bieryla, Allyson; Esquerdo, Gilbert A.; Beichman, Charles A. +10 more
We present here a validation of sub-Saturn exoplanet TOI-181b orbiting a K spectral type star TOI-181 (mass: 0.822 ± 0.04 M⊙, radius: 0.745 ± 0.02 R⊙, temperature: 4994 ± 50 K) as a part of Validation of Transiting Exoplanets using Statistical Tools (VaTEST) project. TOI-181b is a planet with radius 6.95 ± 0.08 R⊕,…
Uranium Abundances and Ages of r-process Enhanced Stars with Novel U II Lines
Beers, Timothy C.; Holmbeck, Erika M.; Hansen, Terese T. +7 more
The ages of the oldest stars shed light on the birth, chemical enrichment, and chemical evolution of the universe. Nucleocosmochronometry provides an avenue to determining the ages of these stars independent from stellar-evolution models. The uranium abundance, which can be determined for metal-poor r-process enhanced (RPE) stars, has been known t…