Search Publications
Hunting for C-rich long-period variable stars in the Milky Way's bar-bulge using unsupervised classification of Gaia BP/RP spectra
Matsunaga, Noriyuki; Sanders, Jason L.
The separation of oxygen- and carbon-rich asymptotic giant branch sources is crucial for their accurate use as local and cosmological distance and age/metallicity indicators. We investigate the use of unsupervised learning algorithms for classifying the chemistry of long-period variables from Gaia DR3's BP/RP spectra. Even in the presence of signi…
Source counts at 7.7-21 µm in CEERS field with JWST
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +8 more
Source counts - the number density of sources as a function of flux density - represent one of the fundamental metrics in observational cosmology due to their straightforward and simple nature. It is an important tool that provides information on galaxy formation and evolution. Source counting is a direct measurement. Compared to advanced analyses…
Bayesian sampling with BeAtlas, a grid of synthetic Be star spectra I. Recovering the fundamental parameters of α Eri and β CMi
Carciofi, A. C.; de Amorim, T. H.; Vieira, R. G. +14 more
Classical B emission (Be) stars are fast rotating, near-main-sequence B-type stars. The rotation and the presence of circumstellar discs profoundly modify the observables of active Be stars. Our goal is to infer stellar and disc parameters, as well as distance and interstellar extinction, using the currently most favoured physical models for these…
Polycyclic aromatic hydrocarbon size tracers
Boersma, C.; Peeters, E.; Maragkoudakis, A. +1 more
We examine the dependence of polycyclic aromatic hydrocarbon (PAH) band intensity ratios as a function of the average number of carbon atoms and assess their effectiveness as tracers for PAH size, utilizing the data, models, and tools provided by the NASA Ames PAH Infrared Spectroscopic Data base. To achieve this, we used spectra from mixtures of …
Coronal line forest AGN - II. Analysis of the spectral energy distribution
Riffel, R.; Rodríguez-Ardila, A.; Panda, S. +3 more
Coronal-Line Forest Active Galactic Nuclei (CLiF AGN) are characterized by strong, high-ionization lines, which are in contrast to what is found in typical AGNs. Here, we carry out an infrared analysis aimed at understanding the spectral energy distribution (SED) of six sources from this group. In this work, the properties of the dusty torus for t…
The Calar Alto CAFOS direct imaging first data release
Cortés-Contreras, M.; Solano, E.; Rodrigo, C. +3 more
We present the first release of the Calar Alto CAFOS direct imaging data, a project led by the Spanish Virtual Observatory with the goal of enhancing the use of the Calar Alto archive by the astrophysics community. Data Release 1 contains 23 903 reduced and astrometrically calibrated images taken from 2008 March to 2019 July with a median of the m…