Search Publications

Correcting Fabry-Pérot etalon effects in solar observations
DOI: 10.1051/0004-6361/202449825 Bibcode: 2024A&A...688A..67S

Blanco Rodríguez, J.; Orozco Suárez, D.; Bailén, F. J. +1 more

Context. Data processing pipelines of Fabry-Pérot interferometers (FPI) must take into account the side effects these devices introduce in the observations. Interpretation of these observations without proper correction can lead to inaccurate or false results, with consequent impact on their physical interpretation. Corrections typically require p…

2024 Astronomy and Astrophysics
SolarOrbiter 0
Skewness and kurtosis of solar wind proton distribution functions: The normal inverse-Gaussian model and its implications
DOI: 10.1051/0004-6361/202347874 Bibcode: 2024A&A...682A..44L

André, N.; Fedorov, A.; Livi, S. +27 more

Context. In the solar wind (SW), the particle distribution functions are generally not Gaussian. They present nonthermal features that are related to underlying acceleration and heating processes. These processes are critical in the overall dynamics of this expanding astrophysical fluid.
Aims: The Proton Alpha Sensor (PAS) on board Solar Orbi…

2024 Astronomy and Astrophysics
SolarOrbiter 0
HR 10 as seen by CHEOPS and TESS: Revealing δ Scuti pulsations, granulation-like signal and hint for transients
DOI: 10.1051/0004-6361/202346180 Bibcode: 2024A&A...690A..73S

Alonso, R.; Deleuil, M.; Erikson, A. +78 more

Context. HR 10 has only recently been identified as a binary system. Previously thought to be an A-type shell star, it appears that both components are fast-rotating A-type stars, each presenting a circumstellar envelope. Although showing complex photometric variability, spectroscopic observations of the metallic absorption lines reveal variation …

2024 Astronomy and Astrophysics
CHEOPS Gaia 0
Unveiling very young O stars. Two Galactic O2V((f*))z in Westerlund 2
DOI: 10.1051/0004-6361/202449474 Bibcode: 2024A&A...685L...5R

Roman-Lopes, A.

Context. O-type stars are known to significantly contribute to both the dynamics and evolution of galaxies. Massive and luminous, they probably control and regulate the galaxies star formation rates. The stellar feedback generated by such cosmic beasts can strongly affect the local star formation rate, with effects in the current (and future) gene…

2024 Astronomy and Astrophysics
Gaia eHST 0
The corona of a fully convective star with a near-polar flare
DOI: 10.1051/0004-6361/202449541 Bibcode: 2024A&A...687A.138I

Stelzer, B.; Poppenhäger, K.; Ilin, E. +1 more

Context. In 2020, the Transiting Exoplanet Survey Satellite (TESS) observed a rapidly rotating M7 dwarf, TIC 277539431, producing a flare at 81° latitude, the highest latitude flare located to date. This is in stark contrast to solar flares that occur much closer to the equator, typically below 30°. The mechanisms that allow flares at high latitud…

2024 Astronomy and Astrophysics
Gaia XMM-Newton 0
Variation in the intensity ratio at each wavelength point of the Si IV 1394/1403 Å lines: Spectral diagnostics of a bifurcated eruption
DOI: 10.1051/0004-6361/202449488 Bibcode: 2024A&A...692A.210Z

Xu, Zhe; Xue, Zhike; Yan, Xiaoli +3 more

Aims. This study aims to investigate the deviation of the intensity ratio of the Si IV 1394 Å and 1403 Å emission lines from the expected value of 2 in the optically thin regime, as has been observed in many recent studies. Methods. We analyzed the integrated intensity ratio (R) and the wavelength-dependent ratio (r(Δλ)) in a small bifurcated erup…

2024 Astronomy and Astrophysics
IRIS 0
The true age of multi-planet host star HD 110067: Or: Don't be fooled by K0V-type stars
DOI: 10.1051/0004-6361/202451619 Bibcode: 2024A&A...691A.322L

Fridlund, Malcolm; Jack, Dennis; Schröder, Klaus-Peter +3 more

HD 110067 is a near (d = 32.22 pc, V = 8.43 mag) K0V star in Coma Ber that was recently discovered to host a six-planet system in stable resonances. The star has a very old age of 8+/‑4 Gyr. However, by the nature of the respective evolution tracks (i.e. with masses of 0.78...0.85 M), which run parallel to the zero-age main sequence fo…

2024 Astronomy and Astrophysics
Gaia 0
The AMBRE Project: Lead abundance in Galactic stars
DOI: 10.1051/0004-6361/202450782 Bibcode: 2024A&A...690A..97C

Recio-Blanco, A.; de Laverny, P.; Contursi, G. +4 more

Context. The chemical evolution of neutron capture elements in the Milky Way is still a matter of debate. Although more and more studies investigate their chemical behaviour, there is still a lack of a significant large sample of abundances of a key heavy element: lead. Aims. Lead is the final product of the s-process nucleosynthesis channel and i…

2024 Astronomy and Astrophysics
Gaia 0
European VLBI Network observations of the peculiar radio source 4C 35.06 overlapping with a compact group of nine galaxies
DOI: 10.1051/0004-6361/202348729 Bibcode: 2024A&A...684A.188V

An, T.; Gabányi, K. É.; Frey, S. +8 more

Context. According to the hierarchical structure formation model, brightest cluster galaxies (BCGs) evolve into the most luminous and massive galaxies in the Universe through multiple merger events. The peculiar radio source 4C 35.06 is located at the core of the galaxy cluster Abell 407, overlapping with a compact group of nine galaxies. Low-freq…

2024 Astronomy and Astrophysics
Gaia 0
Extreme-emission-line galaxies in the MUSE Hubble Ultra Deep Field Survey
DOI: 10.1051/0004-6361/202348185 Bibcode: 2024A&A...688A..28D

Vílchez, J. M.; Iglesias-Páramo, J.; Arroyo-Polonio, A. +1 more


Aims: We aim to apply a methodology to build a sample of extreme-emission-line galaxies (EELGs) using integral field spectroscopy data. In this work, we followed the spectroscopic criteria corresponding to EELG selection and used the MUSE Hubble Ultra-Deep Field Survey, which includes the deepest spectroscopic survey ever performed.
Meth…

2024 Astronomy and Astrophysics
eHST JWST 0