Search Publications
Hydrostatic Equilibrium Constraints in X-COP Galaxy Clusters: Testing Hyperconical Modified Gravity in Hot-gas-dominated Regions
Monjo, Robert
Modified Newtonian dynamics (MOND) was originally proposed to model galaxy rotation curves without dark matter. However, MOND presents difficulties in explaining the radial acceleration relation observed in galaxy clusters, and moreover, it does not completely eliminate the need for dark matter, since it requires using nonluminous particles (e.g.,…
Stellar obliquities of eight close-in gas giant exoplanets
Boffin, H. M. J.; Skarka, M.; Kabath, P. +4 more
The Rossiter–McLaughlin effect allows us to measure the projected stellar obliquity of exoplanets. From the spin-orbit alignment, planet formation and migration theories can be tested to improve our understanding of the currently observed exoplanetary population. Despite having the spin-orbit measurements for more than 200 planets, the stellar obl…
Environmental effects on nearby debris discs
Heras, A. M.; Eiroa, C.; Marshall, J. P. +2 more
Aims. We investigate the influence of the interstellar medium (ISM) on debris discs using a statistical approach. We probe the effect of the ISM on debris disc occurrence rates and on the morphologies of the discs. Methods. We used results from the Herschel Space Observatory DUNES and DEBRIS surveys of 295 nearby FGK dwarf stars imaged at 100 µm a…
On the Hierarchical Relationship Between Type-II Radio Bursts and the Associated Coronal Mass Ejections
Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +3 more
Using Type-II radio bursts from Wind/WAVES and the associated coronal mass ejections (CMEs) from SOHO/LASCO, Gopalswamy et al. (2005) found a hierarchical relationship between the wavelength range of the Type-II bursts and the CME kinetic energy. Under 'DH (Decametric–Hectometric) Type-II bursts', they have included m (metric)-DH, pure DH, and DH-…
Comparative analysis of two episodes of strongly geoeffective coronal mass ejection events in November and December 2023
Romoli, M.; Temmer, M.; Dumbović, M. +8 more
Context. In autumn 2023 a series of close-in-time eruptive events were observed remotely and measured in situ. For that period, we studied a set of analogous events on the Sun, where several coronal mass ejections (CMEs) were launched partly from the same (active) regions close to a coronal hole. The two episodes of events are separated by a full …
The Solar Neighborhood. LII. M Dwarf Twin Binaries—Presumed Identical Twins Appear Fraternal in Variability, Rotation, Hα, and X-Rays
Henry, Todd J.; Osten, Rachel A.; Jao, Wei-Chun +4 more
We present an investigation into the rotation and stellar activity of four fully convective M dwarf "twin" wide binaries. Components in each pair have (1) astrometry confirming they are common-proper-motion binaries, (2) Gaia BP, RP, and 2MASS J, H, and K s magnitudes matching within 0.10 mag, and (3) presumably the same age and compo…
The properties of the Galactic hard X-ray and soft γ-ray background based on 20 years of INTEGRAL/IBIS observations
Krivonos, Roman; Sazonov, Sergey; Shtykovskaya, Ekaterina
We present results of a study of the Galactic hard X-ray and soft γ-ray background emission performed with the IBIS telescope aboard the INTEGRAL observatory using data obtained over more than 20 years of operations. The study of the Galactic background at energies between 10 keV and a few MeV is problematic due to the contribution of point source…
The Origins of Lithium Enhancement in Polluted White Dwarfs
Blouin, Simon; Dufour, Patrick; Clemens, J. Christopher +4 more
The bulk abundances of exoplanetesimals can be measured when they are accreted by white dwarfs. Recently, lithium from the accretion of exoplanetesimals was detected in relatively high levels in multiple white dwarfs. There are presently three proposed hypotheses to explain the detection of excess lithium in white dwarf photospheres: Big Bang and …
A statistical and multiwavelength photometric approach to investigate a young embedded open star cluster: NGC 6193
Medhi, Biman J.; Sheikh, A. H.; Deka, Simanta
We present a statistical and multiwavelength photometric study of the young open cluster NGC 6193. To determine cluster membership, we used an unsupervised ensemble-based machine-learning approach and identified 246 cluster members with a search radius of 30 arcmin using
Effects of cold electron emissions on thermal plasma measurements on board Solar Orbiter spacecraft
Kataria, D. O.; Hellinger, P.; Maksimovic, M. +6 more
Aims. Emissions of photo and secondary electrons influence thermal electron measurements on board spacecraft, typically below a threshold determined by the spacecraft's potential. We aim to examine and quantify this contamination of the observed low-energy electron fluxes. We seek to provide effective constraints for the correction methods used to…