Search Publications
Probability of Forming Gaps in the GD-1 Stream by Close Encounters of Globular Clusters
Hattori, Kohei; Doke, Yuka
One of the most intriguing properties of the GD-1 stellar stream is the existence of three gaps. If these gaps were formed by close encounters with dark matter subhalos, the GD-1 stream opens an exciting window through which we can see the size, mass, and velocity distributions of the dark matter subhalos in the Milky Way. However, in order to use…
V456 Cyg: An eclipsing binary with tidally perturbed g-mode pulsations
Southworth, J.; Bowman, D. M.; Van Reeth, T. +1 more
Context. Many well-known bright stars have been observed by the ongoing transiting exoplanet survey satellite (TESS) space mission. For several of them, these new data reveal previously unobserved variability, such as tidally perturbed pulsations in close binary stars.
Aims: Using newly detected gravity-mode (g-mode) pulsations in V456 Cyg, w…
HAZMAT. VIII. A Spectroscopic Analysis of the Ultraviolet Evolution of K Stars: Additional Evidence for K Dwarf Rotational Stalling in the First Gigayear
Loyd, R. O. Parke; Jackman, James A. G.; Barman, Travis +7 more
Efforts to discover and characterize habitable zone planets have primarily focused on Sun-like stars and M dwarfs. K stars, however, provide an appealing compromise between these two alternatives that has been relatively unexplored. Understanding the ultraviolet (UV) environment around such stars is critical to our understanding of their planets, …
DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy
Fielding, Drummond; Cameron, Alex J.; Kacprzak, Glenn G. +14 more
We compare 500 pc scale, resolved observations of ionized and molecular gas for the z ~ 0.02 starbursting disk galaxy IRAS08339+6517, using measurements from KCWI and NOEMA. We explore the relationship of the star-formation-driven ionized gas outflows with colocated galaxy properties. We find a roughly linear relationship between the outflow mass …
On the Formation of Solar Wind and Switchbacks, and Quiet Sun Heating
Tripathi, Durgesh; Upendran, Vishal
The solar coronal heating in quiet Sun (QS) and coronal holes (CHs), including solar wind formation, are intimately tied by magnetic field dynamics. Thus, a detailed comparative study of these regions is needed to understand the underlying physical processes. CHs are known to have subdued intensity and larger blueshifts in the corona. This work in…
Project Hephaistos - I. Upper limits on partial Dyson spheres in the Milky Way
Wright, Jason T.; Zackrisson, Erik; Korn, Andreas J. +2 more
Dyson spheres are hypothetical megastructures built by advanced extraterrestrial civilizations to harvest radiation energy from stars. Here, we combine optical data from Gaia DR2 with mid-infrared data from AllWISE to set the strongest upper limits to date on the prevalence of partial Dyson spheres within the Milky Way, based on their expected was…
Revisiting a Disky Origin for the Faint Branch of the Sagittarius Stellar Stream
Errani, Raphaël; Famaey, Benoit; Ibata, Rodrigo +2 more
We investigate ways to produce the bifurcation observed in the stellar stream of the Sagittarius dwarf galaxy (Sgr). Our method consists of running N-body simulations of Sgr falling into the Milky Way for the last 3 Gyr, with added test particles on disk orbits that span a wide range of initial positions, energies, and angular momenta. We find tha…
MHD study of the planetary magnetospheric response during extreme solar wind conditions: Earth and exoplanet magnetospheres applications
Pantellini, F.; Zarka, P.; Varela, J. +3 more
Context. The stellar wind and the interplanetary magnetic field modify the topology of planetary magnetospheres. Consequently, the hazardous effect of the direct exposition to the stellar wind, for example, regarding the integrity of satellites orbiting the Earth or the habitability of exoplanets, depends upon the space weather conditions.
Ai…
The stellar 'Snake' - I. Whole structure and properties
Fang, Min; Wang, Fan; Tian, Haijun +10 more
To complement our previous discovery of the young snake-like structure in the solar neighbourhood and reveal the structure's full extent, we build two samples of stars within the Snake and its surrounding territory from Gaia Early Data Release 3 (EDR3). With the friends-of-friends algorithm, we identify 2694 and 9052 Snake member candidates from t…
Molecular gas properties of Planck-selected protocluster candidates at z ≃ 1.3-3
Kneissl, R.; Dole, H.; Frye, B. L. +3 more
We report on IRAM 30-m/EMIR observations of 38 Herschel sources chosen as the brightest red submillimeter (submm) sources in 18 Planck-selected fields drawn from the Planck high-z (PHz) sample of protocluster candidates. These fields host overdensities of red Herschel sources, with high star formation rates (∼10 000 M⊙ yr−1),…