Search Publications
Estimation of surface temperatures on Mercury in preparation of the MERTIS experiment onboard BepiColombo
Hiesinger, Harald; Helbert, Jörn; Bauch, Karin E. +1 more
The Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS) is part of the payload on the joint ESA-JAXA BepiColombo Mission, launched in October 2018. The spectrometer is designed to map surface composition, identify rock-forming minerals, map surface mineralogy, and study surface temperature variations. The surface of Mercury undergoes lar…
The Pristine survey - XIV. Chemical analysis of two ultra-metal-poor stars
Bonifacio, P.; Caffau, E.; Jablonka, P. +15 more
Elemental abundances of the most metal-poor stars reflect the conditions in the early Galaxy and the properties of the first stars. We present a spectroscopic follow-up of two ultra-metal-poor stars ([Fe/H] < -4.0) identified by the survey Pristine: Pristine 221.8781+9.7844 and Pristine 237.8588+12.5660 (hereafter Pr 221 and Pr 237, respectivel…
Possible single-armed spiral in the protoplanetary disk around HD 34282
Ménard, F.; van der Plas, G.; Avenhaus, H. +17 more
Context. During the evolution of protoplanetary disks into planetary systems we expect to detect signatures that trace mechanisms such as planet-disk interaction. Protoplanetary disks display a large variety of structures in recently published high-spatial resolution images. However, the three-dimensional morphology of these disks is often difficu…
The symbiotic recurrent nova V3890 Sgr: binary parameters and pre-outburst activity
Udalski, A.; Mikołajewska, J.; Iłkiewicz, K. +4 more
We present and analyse optical photometry and high-resolution Southern African Large Telescope spectra of the symbiotic recurrent nova V3890 Sgr at quiescence. The orbital period, P = 747.6 d, has been derived from both photometric and spectroscopic data. Our double-line spectroscopic orbits indicate that the mass ratio is q = Mg/M…
A revisited study of Cepheids in open clusters in the Gaia era
Grebel, Eva K.; Medina, Gustavo E.; Lemasle, Bertrand
In this paper, we revisit the problem of identifying bona fide cluster Cepheids by performing an all-sky search for Cepheids associated with open clusters and making use of state-of-the-art catalogued information for both Cepheids and clusters, based on the unparalleled astrometric precision of the second and early third data releases of the Gaia …
Deciphering Star Cluster Evolution by Shape Morphology
Hu, Qingshun; Zhang, Yu; Esamdin, Ali +2 more
We analyze the morphological evolution of open clusters and provide shape parameters for 265 open clusters. The results show that the overall shape of sample clusters becomes more elliptical as they grow older, while their core remains circular or slightly trending to circular. There is a negative correlation of the ellipticities with the number o…
A Preliminary Study of Magnetosphere-Ionosphere-Thermosphere Coupling at Jupiter: Juno Multi-Instrument Measurements and Modeling Tools
Gérard, Jean-Claude; André, Nicolas; Louarn, Philippe +20 more
The dynamics of the Jovian magnetosphere are controlled by the interplay of the planet's fast rotation, its main iogenic plasma source and its interaction with the solar wind. Magnetosphere-Ionosphere-Thermosphere (MIT) coupling processes controlling this interplay are significantly different from their Earth and Saturn counterparts. At the ionosp…
Directly Determined Properties of HD 97658 from Interferometric Observations
Schaefer, Gail H.; Dragomir, Diana; von Braun, Kaspar +5 more
We conducted interferometric observations with the CHARA Array of transiting super-Earth host HD 97658 and measured its limb-darkened angular diameter to be θLD = 0.314 ± 0.004 mas. The combination of the angular diameter with the Gaia EDR3 parallax value with zero-point correction (π = 46.412 ± 0.022 mas, d =21.546 ± 0.011 pc) yields a…
AGN and star formation across cosmic time
Page, M. J.; Symeonidis, M.
We investigate the balance of power between stars and AGN across cosmic history, based on the comparison between the infrared (IR) galaxy luminosity function (LF) and the IR AGN LF. The former corresponds to emission from dust heated by stars and AGN, whereas the latter includes emission from AGN-heated dust only. We find that at all redshifts (at…
A CHEOPS white dwarf transit search
Lendl, Monika; Brandeker, Alexis; Heng, Kevin +2 more
White dwarf spectroscopy shows that nearly half of white dwarf atmospheres contain metals that must have been accreted from planetary material that survived the red giant phases of stellar evolution. We can use metal pollution in white dwarf atmospheres as flags, signalling recent accretion, in order to prioritize an efficient sample of white dwar…