Search Publications
The Optical to Infrared Extinction Law of Magellanic Clouds Based on Red Supergiants and Classical Cepheids
Wang, Shu; Chen, Xiaodian
Precise interstellar dust extinction laws are important to infer the intrinsic properties of reddened objects and correctly interpret observations. In this work, we attempt to measure the optical-infrared extinction laws of the Large and Small Magellanic Clouds (LMC and SMC) by using red supergiant (RSG) stars and classical Cepheids as extinction …
Deciphering the Slow-rise Precursor of a Major Coronal Mass Ejection
Peter, H.; Solanki, S. K.; Aulanier, G. +3 more
Coronal mass ejections are explosive plasma phenomena prevalently occurring on the Sun and probably on other magnetically active stars. However, how their pre-eruptive configuration evolves toward the main explosion remains elusive. Here, based on comprehensive observations of a long-duration precursor in an event on 2012 March 13, we determine th…
Numerical Study on Excitation of Turbulence and Oscillation in Above-the-loop-top Region of a Solar Flare
Reeves, Katharine K.; Takasao, Shinsuke; Shibata, Kengo
Extreme-ultraviolet imaging spectroscopic observations often show an increase in line width around the loop-top or above-the-loop-top (ALT) region of solar flares, suggestive of turbulence. In addition, recent spectroscopic observations found the oscillation in the Doppler velocity around the ALT region. We performed 3D magnetohydrodynamic (MHD) s…
Three Long-period Transiting Giant Planets from TESS
Trifonov, Trifon; Henning, Thomas; Triaud, Amaury H. M. J. +52 more
We report the discovery and orbital characterization of three new transiting warm giant planets. These systems were initially identified as presenting single-transit events in the light curves generated from the full-frame images of the Transiting Exoplanet Survey Satellite. Follow-up radial velocity measurements and additional light curves were u…
A spectral classification system for hydrogen-deficient carbon stars
Ruiter, Ashley J.; Clayton, Geoffrey C.; García-Hernández, D. A. +6 more
Stellar spectral classification has been highly useful in the study of stars. While there is a currently accepted spectral classification system for carbon stars, the subset of hydrogen-deficient carbon (HdC) stars has not been well described by such a system, due predominantly to their rarity and their variability. Here we present the first syste…
The Strength of the Sheared Magnetic Field in the Galactic's Circumnuclear Disk
Lopez-Rodriguez, Enrique; Chuss, David T.; Guerra, Jordan A. +2 more
Recent high-resolution 53 µm polarimetric observations from SOFIA/HAWC+ have revealed the inferred plane-of-the-sky magnetic field (B-field) orientation in the Galactic center's circumnuclear disk (CND). The B-field is mostly aligned with the steamers of ionized material falling onto Sgr A* at large, differential velocities (shear). In such …
Dynamical age of the Tucana-Horologium young stellar association
Bouy, Hervé; Barrado, David; Galli, Phillip A. B. +2 more
The Tucana-Horologium association is one of the closest young stellar groups to the Sun and despite the close proximity its age is still debated in the literature. We take advantage of the state-of-the-art astrometry delivered by the third data release of the Gaia space mission combined with precise radial velocity measurements obtained from high-…
Laboratory Study of Collisionless Magnetic Reconnection
Yamada, M.; Burch, J.; Egedal, J. +13 more
A concise review is given on the past two decades' results from laboratory experiments on collisionless magnetic reconnection in direct relation with space measurements, especially by the Magnetospheric Multiscale (MMS) mission. Highlights include spatial structures of electromagnetic fields in ion and electron diffusion regions as a function of u…
The membership of stars, density profile, and mass segregation in open clusters using a new machine learning-based method
Noormohammadi, M.; Khakian Ghomi, M.; Haghi, H.
A combination of two unsupervised machine learning algorithms, DBSCAN: Density-Based Spatial Clustering of Applications with Noise, and GMM: Gaussian mixture models, are used to find members with a high probability of 12 open clusters, M38, NGC2099, Coma Ber, NGC752, M67, NGC2243, Alessi01, Bochum04, M34, M35, M41, and M48, based on Gaia DR3. Thes…
The Aligned Orbit of the Eccentric Proto Hot Jupiter TOI-3362b
Jordán, Andrés; Brahm, Rafael; Hobson, Melissa J. +8 more
High-eccentricity tidal migration predicts the existence of highly eccentric proto hot Jupiters on the "tidal circularization track," meaning that they might eventually become hot Jupiters, but that their migratory journey remains incomplete. Having experienced moderate amounts of tidal evolution of their orbital elements, proto hot Jupiter system…