Search Publications
HD 28185 revisited: an outer planet, instead of a brown dwarf, on a Saturn-like orbit
Vanderburg, Andrew; Wittenmyer, Robert A.; Huang, Chelsea X. +3 more
As exoplanet surveys reach ever-higher sensitivities and durations, planets analogous to the Solar system giant planets are increasingly within reach. HD 28185 is a Sun-like star known to host a
Radial properties of dust in galaxies: Comparison between observations and isolated galaxy simulations
De Looze, I.; Baes, M.; Palla, M. +8 more
We study the importance of several processes that influence the evolution of dust and its grain size distribution on spatially resolved scales in nearby galaxies. Here, we compiled several multi-wavelength observations for the nearby galaxies NGC 628 (M74), NGC 5457 (M101), NGC 598 (M33), and NGC 300. We applied spatially resolved spectral energy …
Evidence of dark contents in the centre of NGC 6517
Xie, Yi; Zhang, Liyun; Lian, Yujie +3 more
Millisecond pulsars can serve as effective probes to investigate the presence of intermediate-mass black holes (IMBHs) within Galactic globular clusters (GCs). Based on the standard structure models for GCs, we conduct simulations to analyse the distributions of pulsar accelerations within the central region of NGC 6517. By comparing the measured …
Constraints on Acoustic Wave Energy Fluxes and Radiative Losses in the Solar Chromosphere from Non-LTE Inversions
Milić, I.; da Silva Santos, J. M.; de la Cruz Rodríguez, J. +3 more
Accurately assessing the balance between acoustic wave energy fluxes and radiative losses is critical for understanding how the solar chromosphere is thermally regulated. We investigate the energy balance in the chromosphere by comparing deposited acoustic flux and radiative losses under quiet and active solar conditions using non–local thermodyna…
A Self-consistent Data-driven Model for Determining Stellar Parameters from Optical and Near-infrared Spectra
Stassun, Keivan G.; Kounkel, Marina; Chandra, Vedant +3 more
Data-driven models, which apply machine learning to infer physical properties from large quantities of data, have become increasingly important for extracting stellar properties from spectra. In general, these methods have been applied to data in one wavelength regime or another. For example, APOGEE Net has been applied to near-IR spectra from the…
Time Variability of FUV Emission from Cool Stars on Multi-year Timescales
France, Kevin; Youngblood, Allison; Kamgar, Leo
The physical and chemical properties of planetary atmospheres are affected by temporal evolution of ultraviolet (UV) radiation inputs from their host stars at all time scales. While studies of X-ray/UV flare properties and long-term stellar evolution of exoplanet host stars have provided new constraints regarding stellar inputs to exoplanetary sys…
A catalogue of observed geo-effective CME/ICME characteristics
Foldes, Raffaello; Erdélyi, Robertus; Del Moro, Dario +7 more
One of the goals of Space Weather studies is to achieve a better understanding of impulsive phenomena, such as Coronal Mass Ejections (CMEs), to improve our ability to forecast their propagation characteristics and mitigate the risks to our technologically driven society. The essential part of achieving this goal is to assess the performance of fo…
Novel scaling laws to derive spatially resolved flare and CME parameters from sun-as-a-star observables
Mohan, Atul; Akiyama, Sachiko; Gopalswamy, Natchimuthuk +1 more
Coronal mass ejections (CMEs) are often associated with X-ray (SXR) flares powered by magnetic reconnection in the low corona, while the CME shocks in the upper corona and interplanetary (IP) space accelerate electrons often producing the type II radio bursts. The CME and the reconnection event are part of the same energy release process as highli…
Deciphering the evolution of thermodynamic properties and their connection to the global kinematics of high-speed coronal mass ejections using FRIS model
Wang, Yuming; Nieves-Chinchilla, Teresa; Mishra, Wageesh +3 more
Most earlier studies have been limited to estimating the kinematic evolution of coronal mass ejections (CMEs), and only limited efforts have been made to investigate their thermodynamic evolution. We focus on the interplay of the thermal properties of CMEs with their observed global kinematics. We implement the Flux rope Internal State model to es…
Charging effects on Rosetta dust measurements
Deca, Jan; Horányi, Mihály
Dust particles released from comet 67P/Churyumov-Gerasimenko collect electrostatic charges. Their motion is influenced by the electric fields induced by the flow of the solar wind and by the charging of the Rosetta spacecraft itself. Dust grains with sufficiently low tensile strength might even be destroyed en route from the nucleus to Rosetta. A …