Search Publications
Evolved massive stars at low-metallicity. V. Mass-loss rate of red supergiant stars in the Small Magellanic Cloud
Tian, Hao; Yang, Ming; Bonanos, Alceste Z. +17 more
The mass-loss rate (MLR) is one of the most important parameters in astrophysics, because it impacts many areas of astronomy, such as ionizing radiation, wind feedback, star-formation rates, initial mass functions, stellar remnants, supernovae, and so on. However, the most important modes of mass loss are also the most uncertain, as the dominant p…
Confirmation of an He I evaporating atmosphere around the 650-Myr-old sub-Neptune HD 235088 b (TOI-1430 b) with CARMENES
Sánchez-López, A.; López-Puertas, M.; Nagel, E. +31 more
HD 235088 (TOI-1430) is a young star known to host a sub-Neptune-sized planet candidate. We validated the planetary nature of HD 235088 b with multiband photometry, refined its planetary parameters, and obtained a new age estimate of the host star, placing it at 600-800 Myr. Previous spectroscopic observations of a single transit detected an exces…
Dynamical masses of two young transiting sub-Neptunes orbiting HD 63433
Pallé, E.; Béjar, V. J. S.; Montes, D. +7 more
Context. Although the number of exoplanets reported in the literature exceeds 5000 so far, only a few dozen of them are young planets (≤900 Myr). However, a complete characterization of these young planets is key to understanding the current properties of the entire population. Hence, it is necessary to constrain the planetary formation processes …
Variation in optical and infrared properties of galaxies in relation to their surface brightness
Boquien, M.; Małek, K.; Koda, J. +12 more
Although it is now recognized that low surface brightness galaxies (LSBs) constitute a large fraction of the number density of galaxies, many of their properties are still poorly known. Based on only a few studies, LSBs are often considered to be "dust poor", that is, with a very low amount of dust. For the first time, we use a large sample of LSB…
TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf
Nagel, E.; Amado, P. J.; Caballero, J. A. +79 more
We report the discovery, mass, and radius determination of TOI-1801 b, a temperate mini-Neptune around a young M dwarf. TOI-1801 b was observed in TESS sectors 22 and 49, and the alert that this was a TESS planet candidate with a period of 21.3 days went out in April 2020. However, ground-based follow-up observations, including seeing-limited phot…
Asteroseismic age constraints on the open cluster NGC 2477 using oscillating stars identified with TESS FFI
Creevey, O. L.; Palakkatharappil, D. B.
Context. Asteroseismology is one of the few methods to derive ages of individual stars due to the high precision of their observations. Isochrone fitting is a powerful alternative method for deriving ages by studying clusters of stars. Pulsating stars in clusters should therefore allow for detailed studies of the stellar models.
Aims: Our obj…
Search for planets around stars with wide brown dwarfs
Béjar, V. J. S.; Zapatero Osorio, M. R.; Grundahl, F. +6 more
Aims: This work aims to better understand the role of wide brown dwarf companions in planetary systems.
Methods: We obtained high-resolution spectra of six bright stars with co-moving wide substellar companions with the high-resolution SONG, CARMENES, and STELLA spectrographs. We used these spectra to derive radial velocities together wi…
The star in RNO 54: A possible post-FUor with a short faint jet
Moiseev, A. V.; Magakian, T. Yu.; Movsessian, T. A. +2 more
Aims: The aim of the present study is to analyze the spectra of an unusual pre-main sequence star in the cometary nebula RNO 54, which is suspected by several researchers to be a FUori-like object.
Methods: We performed long-slit spectroscopy of the star using the 6m telescope with the SCORPIO-2 multi-mode focal reducer.
Results: We…
The equilibrium shape of (65) Cybele: primordial or relic of a large impact?
Jorda, L.; Carry, B.; Molina, D. +24 more
Context. Cybele asteroids constitute an appealing reservoir of primitive material genetically linked to the outer Solar System, and the physical properties (size and shape) of the largest members can be readily accessed by large (8m class) telescopes.
Aims: We took advantage of the bright apparition of the most iconic member of the Cybele pop…
A deep Hα survey of the Carina tangent arm direction
Zavagno, A.; Elia, D.; Molinari, S. +3 more
Aims: The arm tangent direction provides a unique viewing geometry, with a long path in relatively narrow velocity ranges and lines of view that cross the arm perpendicular to its thickness. The spiral arm tangent regions are therefore the best directions for studying the interstellar medium within spiral density waves in the Milky Way, probi…