Search Publications
The M 101 galaxy group as a node in a nearby cosmic filament
Karachentsev, Igor D.; Karachentseva, Valentina E.; Kaisina, Elena I. +1 more
We performed a search for faint low-surface-brightness dwarf galaxies around the major spiral galaxy M 101 and in the large rectangular area within SGL = [30-80]° and SGB = [10-37]° spanning a chain of galaxies: M 63, M 51, M 101, and NGC 6503. We based our search on data from DESI Legacy Imaging Surveys. We discovered six new probable dwarf membe…
A 600 kpc complex radio source at the center of Abell 3718 discovered by the EMU and POSSUM surveys
Filipović, M. D.; Lovisari, L.; Boschin, W. +10 more
Context. Multifrequency studies of galaxy clusters are crucial for inferring their dynamical states and physics. Moreover, these studies allow us to investigate cluster-embedded sources, whose evolution is affected by the physical and dynamical condition of the cluster itself. So far, these kinds of studies have been preferentially conducted on cl…
A re-analysis of equilibrium chemistry in five hot Jupiters
Drossart, P.; Panek, E.; Beaulieu, J. -P. +4 more
Aims: Studies of chemistry and chemical composition are fundamental to exploring the formation histories of planets and planetary systems. We propose having another look at five targets to better determine their composition and the chemical mechanisms taking place in their atmospheres. We present a re-analysis of five hot Jupiters, combining …
Multi-epoch variability of AT 2000ch (SN 2000ch) in NGC 3432. A radio continuum and optical study
Bomans, Dominik J.; Weis, Kerstin; Dettmar, Ralf-Jürgen +5 more
Context. AT 2000ch is a highly variable massive star and supernova imposter in NGC 3432 first detected in 2000. It is similar and often compared to SN 2009ip, and it is therefore expected to undergo a core-collapse supernova (SN) - a SN imposter of similar brightness - in the near future.
Aims: We characterize the long-term variability of AT …
Simplifying asteroseismic analysis of solar-like oscillators. An application of principal component analysis for dimensionality reduction
Chaplin, W. J.; Davies, G. R.; Nielsen, M. B. +5 more
Context. The asteroseismic analysis of stellar power density spectra is often computationally expensive. The models used in the analysis may require several dozen parameters to accurately describe features in the spectra caused by the oscillation modes and surface granulation. Many of these parameters are often highly correlated, making the parame…
Implications of time-dependent molecular chemistry in metal-poor dwarf stars
Ludwig, H. -G.; Deshmukh, S. A.
Context. Binary molecules such as CO, OH, CH, CN, and C2 are often used as abundance indicators in stars. These species are usually assumed to be formed in chemical equilibrium. The time-dependent effects of hydrodynamics can affect the formation and dissociation of these species and may lead to deviations from chemical equilibrium.
Infrared He I 10830 Å, ultra-violet Ca II, and Mg II chromosphere emissions in the spectra of classical Cepheid X Cyg
Korotin, S. A.; Andrievsky, S. M.; Kovtyukh, V. V.
Aims: In a previous publication, we reported the first detection of emission in the infrared (IR) triplet at 10 830 Å in the spectra of the classical Cepheid X Cyg. Emission is detectable at phases from approximately 0.25 to 0.90. We present and discuss further information on the chromosphere activity of this star, namely International Ultrav…
MoBiDICT: New 3D static models of close synchronised binaries in hydrostatic equilibrium
Dupret, M. -A.; Fellay, L.
Context. In close binary systems, tidal interactions and rotational effects can strongly influence stellar evolution as a result of mass transfer and common envelope phases. These aspects can only be treated following improvements of theoretical models to take into account the breaking of spherical symmetry occurring in close binaries. Current mod…
TDCOSMO. XI. New lensing galaxy redshift and velocity dispersion measurements from Keck spectroscopy of eight lensed quasar systems
Treu, T.; Fassnacht, C. D.; Spiniello, C. +2 more
We have measured the redshifts and single-aperture velocity dispersions of eight lens galaxies using the data collected by the Echellette Spectrograph and Imager (ESI) and Low Resolution Imaging Spectrometer (LRIS) at W.M. Keck observatory on different observing nights spread over three years (2018-2020). These results, combined with other ancilla…
LBT-MODS spectroscopy of high-redshift candidates in the Chandra J1030 field. A newly discovered z ∼ 2.8 large-scale structure
Comastri, Andrea; Signorini, Matilde; Vito, Fabio +13 more
We present the results of a spectroscopic campaign with the Multi-Object Double Spectrograph (MODS) instrument mounted on the Large Binocular Telescope (LBT), aimed at obtaining a spectroscopic redshift for seven Chandra J1030 sources with a photometric redshift ≥2.7 and optical magnitude rAB = [24.5 − 26.5]. We obtained a spectroscopic…