Search Publications
The XXL Survey. L. Active galactic nucleus contamination in galaxy clusters: Detection and cosmological impact
Valtchanov, Ivan; Vignali, Cristian; Aguena, Michel +12 more
Context. X-ray observations of galaxy clusters are impacted by the presence of active galactic nuclei (AGNs) in a manner that is challenging to quantify, leading to biases in the detection and measurement of cluster properties for both astrophysics and cosmological applications.
Aims: We detect and characterise clusters contaminated by centra…
FORECAST: A flexible software to forward model cosmological hydrodynamical simulations mimicking real observations
Santini, Paola; Castellano, Marco; Fontana, Adriano +7 more
Context. Comparing theoretical predictions to real data is crucial to properly formulate galaxy formation theories. However, this is usually done naively considering the direct output of simulations and quantities inferred from observations, which can lead to severe inconsistencies.
Aims: We present FORECAST, a new flexible and adaptable soft…
A LAMOST Spectroscopic Study of T Tauri Stars in the Orion OB1a Subassociation
Zhu, Zhaohuan; Calvet, Nuria; Yuan, Haibo +9 more
We present a spectroscopic analysis of T Tauri stars (TTSs) observed with the wide-field multifiber spectrograph LAMOST in the substellar associations Ori OB1a located in the Orion Star-forming Complex. Based on GAIA-DR3 data, we selected stars with proper motions and parallaxes expected for TTSs belonging to the young association. We perform a sp…
Detecting New Visual Binaries in Gaia DR3 with Gaia and Two Micron All Sky Survey (2MASS) Photometry. I. New Candidate Binaries within 200 pc of the Sun
Lépine, Sébastien; Medan, Ilija
We present a method to identify likely visual binaries in Gaia eDR3 that does not rely on parallax or proper motion. This method utilizes the various point-spread function sizes of Two Micron All Sky Survey (2MASS)/Gaia, where at <2.″5 two stars may be unresolved in 2MASS but resolved by Gaia. Due to this, if close neighbors listed in Gaia are …
A systematic survey of millimetre-wavelength flaring variability of young stellar objects in the Orion Nebula Cluster
Menten, K. M.; Güdel, M.; Hacar, A. +3 more
High-energy processes are ubiquitous even in the earliest stages of protostellar evolution. Motivated by the results of our systematic search for intense centimetre radio flares in Young Stellar Objects (YSOs) and by rare findings of strong millimetre-wavelength variability, we have conducted a systematic search for such variability in the Orion N…
The LSST AGN Data Challenge: Selection Methods
Ni, Qingling; Paolillo, Maurizio; Richards, Gordon T. +12 more
Development of the Rubin Observatory Legacy Survey of Space and Time (LSST) includes a series of Data Challenges (DCs) arranged by various LSST Scientific Collaborations that are taking place during the project's preoperational phase. The AGN Science Collaboration Data Challenge (AGNSC-DC) is a partial prototype of the expected LSST data on active…
A Comprehensive Perturbative Formalism for Phase Mixing in Perturbed Disks. II. Phase Spirals in an Inhomogeneous Disk Galaxy with a Nonresponsive Dark Matter Halo
van den Bosch, Frank C.; Banik, Uddipan; Weinberg, Martin D.
We develop a linear perturbative formalism to compute the response of an inhomogeneous stellar disk embedded in a nonresponsive dark matter (DM) halo to various perturbations like bars, spiral arms, and encounters with satellite galaxies. Without self-gravity to reinforce it, the response of a Fourier mode phase mixes away due to an intrinsic spre…
Formation of the Mg II h and k Polarization Profiles in a Solar Plage Model and Their Suitability to Infer Magnetic Fields
Afonso Delgado, David; del Pino Alemán, Tanausú; Trujillo Bueno, Javier
The Mg II h and k lines are among the strongest in the near-ultraviolet solar spectrum and their line core originates in the upper chromosphere, just below the transition region. Consequently, they have become one of the main targets for investigating the magnetism of the upper solar atmosphere. The recent Chromospheric Layer Spectropolarimeter (C…
Binary masses and luminosities with Gaia DR3
Arenou, F.; Babusiaux, C.; Merle, T. +1 more
Context. The recent third data release (DR3) of Gaia has brought some new exciting data about stellar binaries. It provides new opportunities to fully characterize more stellar systems and contributes to enriching our global knowledge of stellar behaviour.
Aims: By combining the new Gaia non-single stars catalogue with double-lined spectrosco…
The Ly α, C IV, and He II nebulae around J1000+0234: a galaxy pair at the centre of a galaxy overdensity at z = 4.5
Magnelli, B.; Smolčić, V.; Gómez-Guijarro, C. +7 more
Ly α λ1216 (Ly α) emission extending over $\gtrsim \, \rm 10\, kilo\,parsec\, (kpc)$ around dusty, massive starbursts at z ≳ 3 might represent a short-lived phase in the evolution of present-day, massive quiescent galaxies. To obtain empirical constraints on this emerging scenario, we present Ly α, C IVλ1550 (C IV), and He II λ1640 (He II) observa…