Search Publications

Variability in hot sub-luminous stars and binaries: Machine-learning analysis of Gaia DR3 multi-epoch photometry
DOI: 10.1051/0004-6361/202452429 Bibcode: 2025A&A...693A.268R

Groot, P. J.; Aerts, C.; Ranaivomanana, P. +3 more

Context. Hot sub-luminous stars represent a population of stripped and evolved red giants that is located on the extreme horizontal branch. Since they exhibit a wide range of variability due to pulsations or binary interactions, it is crucial to unveil their intrinsic and extrinsic variability to understand the physical processes of their formatio…

2025 Astronomy and Astrophysics
Gaia 0
Alpha–Proton Relative Drift: Implications for the Origins and Dynamics of the Solar Wind
DOI: 10.3847/2041-8213/ad9ddd Bibcode: 2025ApJ...978L..17W

Matteini, Lorenzo; Wang, Joseph H.; Horbury, Timothy S. +1 more

Helium nuclei (alpha particles) strongly influence the momentum and energy balance in the solar wind, comprising up to 20% of the solar wind mass density. In fast Alfvénic wind at heliocentric distances greater than 0.3 au, the alpha particles' bulk flow speed is systematically different to that of the protons. This relative drift speed is of unkn…

2025 The Astrophysical Journal
SolarOrbiter 0
Spectral analysis of ultraluminous X-ray pulsars with models of X-ray pulsars
DOI: 10.1093/mnras/stae2558 Bibcode: 2025MNRAS.536..340K

Paul, Biswajit; Sharma, Rahul; Kumar, Manish +1 more

A fraction of the ultraluminous X-ray (ULX) sources are known to be accreting neutron stars as they show coherent X-ray pulsations with pulse periods ranging from ${\sim} 1{\!-\!}30$ s. While initially thought to host intermediate-mass black holes, ULXs have since b…

2025 Monthly Notices of the Royal Astronomical Society
XMM-Newton 0
Stellar magnetic activity in Earth 2.0 candidates based on LAMOST DR10
DOI: 10.1051/0004-6361/202452042 Bibcode: 2025A&A...694A.157S

Zhang, Liyun; Han, Xianming L.; Misra, Prabhakar +3 more

Aims. Stellar chromospheric activity can impact the search for exoplanets. Earth 2.0 (ET 2.0) is a space telescope designed for exoplanet detection. In this work, we survey the stellar chromospheric activity in the ET 2.0 target regions to enhance the detection rate of exoplanets. Methods. This work uses Hα and Ca II H&K lines as indicators of chr…

2025 Astronomy and Astrophysics
Gaia 0
Origin of the Unusual Composition of 3He-rich Solar Energetic Particles
DOI: 10.3847/1538-4357/adb48d Bibcode: 2025ApJ...981..178B

Wimmer-Schweingruber, Robert F.; Rodríguez-Pacheco, Javier; Ho, George C. +3 more

We examine 3He-rich solar energetic particles (SEPs) detected on 2023 October 24–25 by Solar Orbiter at 0.47 au. Measurements reveal that heavy-ion enhancements increase irregularly with mass, peaking at S. C, and especially N, Si, and S, stand out in the enhancement pattern with large abundances. Except for 3He, heavy-ion sp…

2025 The Astrophysical Journal
SOHO SolarOrbiter 0
Filling the Gap: The Missing Eclipses of γ Persei from 2005 and from 2006
DOI: 10.3847/1538-3881/adb60d Bibcode: 2025AJ....169..196A

Molnár, László; Ádám, Rozália Z.

γ Persei is a long-period (P ≈ 14.6 yr) eclipsing binary system. Its period makes it a difficult target to fully understand: so far, only two primary eclipses are known in the literature, from 1990 and from 2019, whereas the 2005 one was missed due to its closeness to the Sun at the time. We aimed to fill in this gap by processing the quasi-contin…

2025 The Astronomical Journal
Gaia 0
3D Nonequilibrium Ionization and Spectroscopic Modeling of Coronal Mass Ejections. I. Comparison with Hinode/EIS Observations
DOI: 10.3847/1538-4357/ada7e8 Bibcode: 2025ApJ...980...30W

Landi, E.; Manchester, W. B.; Wraback, E. M. +1 more

High-resolution EUV spectroscopy provides an informative diagnostic tool for the early evolution of coronal mass ejections (CMEs) since it can directly measure many physical properties of CME plasma close to the Sun that cannot be determined from white-light coronagraphs or narrowband imagers. The Hinode/EUV Imaging Spectrometer (EIS) captured a s…

2025 The Astrophysical Journal
Hinode 0
Exploring the empirical instability strip for γ Dor-type stars in eclipsing binaries
DOI: 10.1093/mnras/staf330 Bibcode: 2025MNRAS.538..726C

Çakırlı, Ö.; Bilir, S.; Özdarcan, O. +1 more

This research paper has light-curve modelling, spectroscopy, and detailed asteroseismic studies for five detached eclipsing binaries with a $\gamma$ Dor component that have been found so far by the sky surveys. The objective is to study the pulsational characteristi…

2025 Monthly Notices of the Royal Astronomical Society
Gaia 0
Modified Masses and Parallaxes of the Close Visual Triple System HD 2893
DOI: 10.1088/1674-4527/ada8ee Bibcode: 2025RAA....25b5011M

Masda, Suhail; Al-Wardat, Mashhoor; Aljboor, Hussam +4 more

We present the essential stellar parameters of the close visual triple system HD 2893 using Al-Wardat's method for analyzing binary and multiple star systems in conjunction with Kurucz's model atmospheres. This method accurately computes the spectrophotometric stellar masses through a combined synthetic spectral energy distribution approach that c…

2025 Research in Astronomy and Astrophysics
Gaia Hipparcos 0
A Case Study of Interstellar Material Delivery: α Centauri
DOI: 10.3847/PSJ/adb1e9 Bibcode: 2025PSJ.....6...56G

Wiegert, Paul A.; Gregg, Cole R.

Interstellar material has been discovered in our solar system, yet its origins and details of its transport are unknown. Here, we present α Centauri as a case study of the delivery of interstellar material to our solar system. α Centauri is a mature triple star system that likely harbors planets, and is moving toward us with the point of the close…

2025 The Planetary Science Journal
Ulysses 0