Search Publications
Obliquity measurement and atmospheric characterisation of the WASP-74 planetary system
Tamura, M.; Pallé, E.; Béjar, V. J. S. +27 more
We present new transit observations of the hot Jupiter WASP-74 b (Teq ~ 1860 K) using the high-resolution spectrograph HARPS-N and the multi-colour simultaneous imager MuSCAT2. We refined the orbital properties of the planet and its host star and measured its obliquity for the first time. The measured sky-projected angle between the ste…
Asteroid mass estimation with the robust adaptive Metropolis algorithm
Granvik, M.; Siltala, L.
Context. The bulk density of an asteroid informs us about its interior structure and composition. To constrain the bulk density, one needs an estimated mass of the asteroid. The mass is estimated by analyzing an asteroid's gravitational interaction with another object, such as another asteroid during a close encounter. An estimate for the mass has…
2MASS J15491331-3539118: a new low-mass wide companion of the GQ Lup system
Alcalá, J. M.; Manara, C. F.; D'Orazi, V. +14 more
Substellar companions at wide separation around stars hosting planets or brown dwarfs (BDs) yet close enough for their formation in the circumstellar disc are of special interest. In this Letter we report the discovery of a wide (projected separation ∼16.0", or 2400 AU, and position angle 114.61°) companion of the GQ Lup A-B system, most likely gr…
The post-common-envelope binary central star of the planetary nebula PN G283.7-05.1. A possible post-red-giant-branch planetary nebula central star
Corradi, R. L. M.; Boffin, H. M. J.; Jones, D. +8 more
We present the discovery and characterisation of the post-common-envelope central star system in the planetary nebula PN G283.7-05.1. Deep images taken as part of the POPIPlaN survey indicate that the nebula may possess a bipolar morphology similar to other post-common-envelope planetary nebulae. Simultaneous light and radial velocity curve modell…
The search for disks or planetary objects around directly imaged companions: a candidate around DH Tauri B
Ertel, S.; Henning, T.; Brandner, W. +45 more
Context. In recent decades, thousands of substellar companions have been discovered with both indirect and direct methods of detection. While the majority of the sample is populated by objects discovered using radial velocity and transit techniques, an increasing number have been directly imaged. These planets and brown dwarfs are extraordinary so…
Lithium-rotation connection in the newly discovered young stellar stream Psc-Eri (Meingast 1)
Bayo, A.; Bouy, H.; Bouvier, J. +4 more
Context. As a fragile element, lithium is a sensitive probe of physical processes occurring in stellar interiors.
Aims: We aim to investigate the relationship between lithium abundance and rotation rate in low-mass members of the newly discovered 125 Myr-old Psc-Eri stellar stream.
Methods: We obtained high-resolution optical spectra and…
Propagation of waves above a plage as observed by IRIS and SDO
Srivastava, A. K.; Mathioudakis, M.; Jelínek, P. +2 more
Context. Magnetohydrodynamic waves are proposed as the mechanism that transport sufficient energy from the photosphere to heat the transition region (TR) and corona. However, various aspects of these waves, such as their nature, propagation characteristics, and role in the atmospheric heating process, remain poorly understood and require further i…
Prospects for measuring Mercury's tidal Love number h2 with the BepiColombo Laser Altimeter
Oberst, J.; Iess, L.; Kallenbach, R. +7 more
Context. The Love number h2 describes the radial tidal displacements of Mercury's surface and allows constraints to be set on the inner core size when combined with the potential Love number k2. Knowledge of Mercury's inner core size is fundamental to gaining insights into the planet's thermal evolution and dynamo working pri…
Three open clusters containing Cepheids: NGC 6649, NGC 6664, and Berkeley 55
Castro, N.; Negueruela, I.; Tabernero, H. M. +2 more
Classical Cepheids in open clusters play an important role in benchmarking stellar evolution models, in addition to anchoring the cosmic distance scale and invariably securing the Hubble constant. Three pertinent clusters hosting classical Cepheids and red (super)giants are: NGC 6649, NGC 6664, and Berkeley 55. These clusters form the basis of ana…
Quiet-Sun hydrogen Lyman-α line profile derived from SOHO/SUMER solar-disk observations
Heinzel, P.; Gunár, S.; Schwartz, P. +1 more
Context. The solar radiation in the Lyman-α spectral line of hydrogen plays a significant role in the illumination of chromospheric and coronal structures, such as prominences, spicules, chromospheric fibrils, cores of coronal mass ejections, and solar wind. Moreover, it is important for the investigation of the heliosphere, Earth's ionosphere, an…