Search Publications
Clustered star formation toward Berkeley 87/ON2. I. Multiwavelength census and the population overlap problem
Alves, João; Garcia, Miriam; Jiménez-Bailón, Elena +3 more
Context. Disentangling line-of-sight alignments of young stellar populations is crucial for observational studies of star-forming complexes. This task is particularly problematic in a Cygnus-X subregion where several components, located at different distances, overlap: the Berkeley 87 young massive cluster, the poorly known [DB2001] Cl05 embedded …
Possibility of concentration of nonvolatile species near the surface of comet 67P/Churyumov-Gerasimenko
Nomura, H.; Majumdar, L.; Suzuki, T. +4 more
Context. Cometary materials are thought to be the reservoir of the primitive materials of the Solar System. The recent detection of glycine and CH3NH2 by the ROSINA mass spectrometer in the coma of 67P/Churyumov-Gerasimenko suggests that amino acids and their precursors may have formed in an early evolutionary phase of the So…
Spectral evolution of X-ray pulsar 4U 1901+03 during the 2019 outburst based on Insight-HXMT and NuSTAR observations
Zhang, Shu; Doroshenko, Victor; Tsygankov, Sergey S. +7 more
We report on a detailed spectral analysis of emission from X-ray pulsar 4U 1901+03 using data obtained by the Insight-HXMT and NuSTAR observatories during the 2019 outburst of the source. Thanks to the extensive coverage of the outburst by Insight-HXMT, we were able to investigate the spectral evolution of the source as a function of flux, and com…
X-ray analysis of the Planck-detected triplet-cluster system PLCK G334.8-38
Pointecouteau, Etienne; Douspis, Marian; Aghanim, Nabila +2 more
We conducted an X-ray analysis of one of the two Planck-detected triplet-cluster systems, PLCK G334.8-38.0, with a ∼100 ks deep XMM-Newton data. We find that the system has a redshift of z = 0.37 ± 0.01 but the precision of the X-ray spectroscopy for two members is too low to rule out a projected triplet system, demanding optical spectroscopy for …
Long-term, orbital, and rapid variations of the Be star V923 Aql = HD 183656
Wolf, M.; Harmanec, P.; Bakış, V. +9 more
We present the latest results of a long-term observational project aimed at observing, collecting from the literature, and homogenising the light, colour, and spectral variations of the well-known emission-line Be star V923 Aql. Our analysis of these parameters confirms that all of the observables exhibit cyclic changes with variable cycle length …
The dust-star interplay in late-type galaxies at z < 0.5: Forecasts for the JWST
Baes, Maarten; Bendo, George J.; Fritz, Jacopo +4 more
Context. In recent years, significant growth in the amount of data available to astronomers has opened up the possibility for extensive multi-wavelength approaches. In the field of galaxy evolution, such approaches have uncovered fundamental correlations, linking the dust component of a galaxy to its star formation rate (SFR). Despite these achiev…
The star catalogue of Wilhelm IV, Landgraf von Hessen-Kassel. Accuracy of the catalogue and of the measurements
Verbunt, Frank; Schrimpf, Andreas
We analyse a manuscript star catalogue by Wilhem IV, Landgraf von Hessen-Kassel from 1586. From measurements of altitudes and of angles between stars, given in the catalogue, we find that the measurement accuracy averages 26″ for eight fundamental stars, compared to 49″ of the measurements by Brahe. The computation in converting altitudes to decli…
XMM-Newton spectrum of the radio-loud quasar 3C 215: Slim accretion disk or SMBH binary
Tombesi, F.; Mei, A.
Context. Radio-loud active galactic nuclei (RL AGN) exhibit very powerful jet emission in the radio band, while the radio-quiet (RQ) AGN do not. This RL-RQ dichotomy would imply a sharp difference existing among these two classes, however, modern theoretical models and observations suggest a common nuclear environment that is possibly characterize…
Predicting far-infrared maps of galaxies via machine learning techniques
Baes, Maarten; Dobbels, Wouter
Context. The ultraviolet (UV) to sub-millimetre spectral energy distribution of galaxies can be roughly divided into two sections: the stellar emission (attenuated by dust) at UV to near-infrared wavelengths and dust emission at longer wavelengths. In Dobbels et al. (2020, A&A, 634, A57), we show that these two sections are strongly related, a…
Refined fundamental parameters of Canopus from combined near-IR interferometry and spectral energy distribution
Millour, F.; Zorec, J.; Domiciano de Souza, A. +3 more
Context. Canopus, the brightest and closest yellow supergiant to our Solar System, offers a unique laboratory for understanding the physics of evolved massive stars.
Aims: We aim at quantitatively exploring a large space of fundamental parameters of Canopus based on the combined analysis of its spectral energy distribution (SED) and optical-I…