Search Publications

Precise characterisation of HD 15337 with CHEOPS: A laboratory for planet formation and evolution
DOI: 10.1051/0004-6361/202347759 Bibcode: 2024A&A...686A.282R

Guterman, P.; Alonso, R.; Deleuil, M. +90 more

Context. The HD 15337 (TIC 120896927, TOI-402) system was observed by the Transiting Exoplanet Survey Satellite (TESS), revealing the presence of two short-period planets situated on opposite sides of the radius gap. This offers an excellent opportunity to study theories of formation and evolution, as well as to investigate internal composition an…

2024 Astronomy and Astrophysics
CHEOPS Gaia 3
Stellar angular momentum of intermediate-redshift galaxies in MUSE surveys
DOI: 10.1051/0004-6361/202449758 Bibcode: 2024A&A...688A..75M

Krajnović, D.; Contini, T.; Pessa, I. +8 more

We quantify the stellar rotation of galaxies by computing the λR parameter, a proxy for the stellar angular momentum in a sample of 106 intermediate-redshift galaxies (0.1 < z < 0.8). The sample is located in the CANDELS/GOODS-S and CANDELS/COSMOS regions, and it was observed by various MUSE surveys. We created spatially resolved …

2024 Astronomy and Astrophysics
eHST 3
Disentangling the X-ray variability in the Lyman continuum emitter Haro 11
DOI: 10.1051/0004-6361/202449388 Bibcode: 2024A&A...689A.333D

Östlin, G.; Herenz, E. C.; Silich, S. +1 more

Context. Lyman break analogs in the local Universe serve as counterparts to Lyman break galaxies (LBGs) at high redshifts, which are widely regarded as major contributors to cosmic reionization in the early stages of the Universe. Aims. We studied XMM-Newton and Chandra observations of the nearby LBG analog Haro 11, which contains two X-ray-bright…

2024 Astronomy and Astrophysics
XMM-Newton eHST 3
The MUSE eXtremely Deep Field: Detections of circumgalactic Si II* emission at z ≳ 2
DOI: 10.1051/0004-6361/202451009 Bibcode: 2024A&A...691A.255K

Ouchi, Masami; Blaizot, Jérémy; Garel, Thibault +17 more

Context. The circumgalactic medium (CGM) serves as a baryon reservoir that connects galaxies to the intergalactic medium and fuels star formation. The spatial distribution of the metal-enriched cool CGM has not yet been directly revealed at cosmic noon (z ≃ 2–4), as bright emission lines at these redshifts are not covered by optical integral field…

2024 Astronomy and Astrophysics
eHST 3
Efficiency of solar microflares in accelerating electrons when rooted in a sunspot
DOI: 10.1051/0004-6361/202348295 Bibcode: 2024A&A...683A..41S

Krucker, Säm; Veronig, Astrid M.; Dickson, Ewan C. M. +3 more

Context. The spectral shape of the X-ray emission in solar flares varies with the event size, with small flares generally exhibiting softer spectra than large events, indicative of a relatively lower number of accelerated electrons at higher energies.
Aims: We investigate two microflares of GOES classes A9 and C1 (after background subtraction…

2024 Astronomy and Astrophysics
SolarOrbiter 3
HR-GO: I. Comprehensive NLTE abundance analysis of the Cetus stream
DOI: 10.1051/0004-6361/202450981 Bibcode: 2024A&A...690A.331S

Sestito, F.; Sitnova, T. M.; Mashonkina, L. I. +8 more

Context. Dwarf galaxy streams encode vast amounts of information essential to understanding early galaxy formation and nucleosynthesis channels. Due to the variation in the timescales of star formation history in their progenitors, stellar streams serve as 'snapshots' that record different stages of galactic chemical evolution. Aims. This study fo…

2024 Astronomy and Astrophysics
Gaia 3
Exsolution process in white dwarf stars
DOI: 10.1051/0004-6361/202348344 Bibcode: 2024A&A...683A.101C

Rebassa-Mansergas, Alberto; Torres, Santiago; Camisassa, Maria +1 more

Context. White dwarf stars are considered to be suitable cosmic laboratories for studying the physics of dense plasma. Furthermore, the use of white dwarf stars as cosmic clocks to date stellar populations and main sequence companions demands an appropriate understanding of the physics of white dwarfs in order to provide precise ages for these sta…

2024 Astronomy and Astrophysics
Gaia 3
Periodic variable A-F spectral type stars in the southern TESS continuous viewing zone. I. Identification and classification
DOI: 10.1051/0004-6361/202450711 Bibcode: 2024A&A...688A..25S

Skarka, M.; Henzl, Z.


Aims: Our primary objective is to accurately identify and classify the variability of A-F stars in the southern continuous viewing zone of the TESS satellite. The brightness limit was set to 10 mag to ensure the utmost reliability of our results and allow for spectroscopic follow-up observations using small telescopes. We aim to compare our f…

2024 Astronomy and Astrophysics
Gaia 3
Transition region response to quiet-Sun Ellerman bombs
DOI: 10.1051/0004-6361/202450070 Bibcode: 2024A&A...689A.156B

Joshi, Jayant; Rouppe van der Voort, Luc; Bhatnagar, Aditi

Context. Quiet-Sun Ellerman bombs (QSEBs) are key indicators of small-scale photospheric magnetic reconnection events. Recent high-resolution observations have shown that they are ubiquitous and that large numbers of QSEBs can be found in the quiet Sun. Aims. We aim to understand the impact of QSEBs on the upper solar atmosphere by analyzing their…

2024 Astronomy and Astrophysics
IRIS 3
Inferring the distribution of the ionising photon escape fraction
DOI: 10.1051/0004-6361/202450747 Bibcode: 2024A&A...692A..57K

Mason, Charlotte A.; Cullen, Fergus; McLure, Ross J. +2 more

Context. The escape fraction of ionising photons from galaxies (fesc) is a key parameter for understanding how intergalactic hydrogen became reionised, but it remains mostly unconstrained. Measurements have been limited to the average value in galaxy ensembles and to handfuls of individual detections. Aims. To help understand which mech…

2024 Astronomy and Astrophysics
eHST 3