Search Publications

The relationship between bipolar magnetic regions and their sunspots
DOI: 10.1051/0004-6361/202141336 Bibcode: 2021A&A...654A..28Y

Solanki, S. K.; Yeo, K. L.; Krivova, N. A. +1 more

Context. The relationship between bipolar magnetic regions (BMRs) and their sunspots is an important property of the solar magnetic field, but it is not well constrained. One consequence is that it is a challenge for surface flux transport models (SFTMs) based on sunspot observations to determine the details of BMR emergence, which they require as…

2021 Astronomy and Astrophysics
SOHO 4
A survey of IRAS young stellar object candidates. Searching for large-scale Herbig-Haro objects
DOI: 10.1051/0004-6361/202037752 Bibcode: 2021A&A...648A..57L

Estalella, Robert; Riera, Angels; López, Rosario +1 more

Context. Jets and outflows are associated with young stellar objects across the stellar mass spectrum, from brown dwarf protostars to massive Ae/Be stars. Frequently the jet morphology is spatially discontinuous because of the temporal variability of the ejection from the driving source. Images covering a wide field of view around the jet-driving …

2021 Astronomy and Astrophysics
Gaia eHST 4
Spatial distribution of the aromatic and aliphatic carbonaceous nanograin features in the protoplanetary disk around HD 100546
DOI: 10.1051/0004-6361/201936388 Bibcode: 2021A&A...649A..84H

Pantin, E.; Ysard, N.; Habart, E. +4 more

Context. Carbonaceous nanograins are present at the surface of protoplanetary disks around Herbig Ae/Be stars, where most of the ultraviolet energy from the central star is dissipated. Efficiently coupled to the gas, they are unavoidable to understand the physics and chemistry of these disks. Furthermore, nanograins are able to trace the outer fla…

2021 Astronomy and Astrophysics
Gaia ISO 4
Phase-resolved hard X-ray emission of the high-mass binary LS 5039: a spectral hardening above 50 keV detected with INTEGRAL
DOI: 10.1051/0004-6361/202141102 Bibcode: 2021A&A...654A.127F

Bozzo, E.; Bykov, A. M.; Krassilchtchikov, A. M. +3 more


Aims: LS 5039 is an enigmatic high-mass gamma-ray binary which hosts a powerful O6.5V companion, but the nature of the compact object is still to be established using multi-wavelength observations.
Methods: We analyzed phase-resolved multi-instrument spectra of nonthermal emission from LS 5039 in order to produce reliable spectral models…

2021 Astronomy and Astrophysics
INTEGRAL XMM-Newton 4
Possible substellar companions in dwarf eclipsing binaries. SDSS J143547.87+373338.5, NSVS 7826147, and NSVS 14256825
DOI: 10.1051/0004-6361/202039851 Bibcode: 2021A&A...647A..65W

Merc, J.; Wolf, M.; Zejda, M. +4 more

We present the new results of our long-term observational project to detect the small variations in the orbital periods of low-mass and short-period eclipsing binaries. About 120 new precise mid-eclipse times were obtained for three relatively well-known dwarf eclipsing binaries: SDSS J143547.87+373338.5 (P = 0.126 d), NSVS 07826147 (0.162 d), and…

2021 Astronomy and Astrophysics
Gaia 4
New mid-infrared imaging constraints on companions and protoplanetary disks around six young stars
DOI: 10.1051/0004-6361/202039261 Bibcode: 2021A&A...648A..92P

Waters, L. B. F. M.; Kamp, I.; Quanz, S. P. +13 more

Context. Mid-infrared (mid-IR) imaging traces the sub-micron and micron-sized dust grains in protoplanetary disks and it offers constraints on the geometrical properties of the disks and potential companions, particularly if those companions have circumplanetary disks.
Aims: We use the VISIR instrument and its upgrade NEAR on the VLT to take …

2021 Astronomy and Astrophysics
AKARI Gaia ISO 4
Herschel and Odin observations of H2O, CO, CH, CH+, and [N II] in the barred spiral galaxy NGC 1365. Bar-induced activity in the outer and inner circumnuclear tori
DOI: 10.1051/0004-6361/202038875 Bibcode: 2021A&A...647A..86S

Larsson, B.; Rydbeck, G.; Frisk, U. +3 more

Context. The Odin satellite is now into its twentieth year of operation, much surpassing its design life of two years. One of its major astronomical pursuits was the search for and study of water vapor in diverse regions of the Solar System and the Milky Way galaxy. The Herschel space observatory was needed to detect water vapor in external galaxi…

2021 Astronomy and Astrophysics
Herschel 4
Characterising atmospheric gravity waves on the nightside lower clouds of Venus: a systematic analysis
DOI: 10.1051/0004-6361/202040193 Bibcode: 2021A&A...649A..34S

Lebonnois, S.; Machado, P.; Peralta, J. +3 more

We present the detection and characterisation of mesoscale waves on the lower clouds of Venus using images from the Visible Infrared Thermal Imaging Spectrometer onboard the European Venus Express space mission and from the 2 µm camera (IR2) instrument onboard the Japanese space mission Akatsuki. We used image navigation and processing techn…

2021 Astronomy and Astrophysics
VenusExpress 4
Multi-epoch properties of the warm absorber in the Seyfert 1 galaxy NGC 985
DOI: 10.1051/0004-6361/202040045 Bibcode: 2021A&A...653A.125E

Kaastra, J. S.; Kriss, G. A.; Ebrero, J. +1 more

Context. NGC 985 was observed by XMM-Newton twice in 2015, revealing that the source was coming out from a soft X-ray obscuration event that took place in 2013. These kinds of events are possibly recurrent since a previous XMM-Newton archival observation in 2003 also showed signatures of partial obscuration.
Aims: We have analyzed the high-re…

2021 Astronomy and Astrophysics
XMM-Newton eHST 4
First detection of a disk free of volatile elements around a young A-type star: A possible sign of collisions between rocky planets
DOI: 10.1051/0004-6361/202141070 Bibcode: 2021A&A...651L..11V

Manara, C. F.; Miles-Páez, P. A.; van den Ancker, M. E. +7 more


Aims: We present the first detailed analysis of the astrophysical parameters of the poorly studied Sco-Cen member HD 152384 and its circumstellar environment.
Methods: We analyse newly obtained optical-near-IR X-shooter spectra, as well as archival TESS data, of HD 152384. In addition, we use literature photometric data to construct a de…

2021 Astronomy and Astrophysics
Gaia 4