Search Publications
Consistent Analysis of the AGN LF in X-Ray and MIR in the XMM-LSS Field
Clements, D. L.; Brandt, W. N.; Nyland, Kristina +9 more
The luminosity function of active galactic nuclei (AGN) probes the history of supermassive black hole assembly and growth across cosmic time. To mitigate selection biases, we present a consistent analysis of the AGN luminosity functions (LFs) derived for both X-ray and mid-infrared (MIR) selected AGN in the XMM-Large Scale Structure field. There a…
disnht: Modeling X-ray absorption from distributed column densities
Bianchi, Stefano; Ponti, Gabriele; Locatelli, Nicola
Collecting and analyzing X-ray photons over either spatial or temporal scales encompassing varying optical depth values requires knowledge about the optical depth distribution. For a sufficiently broad optical depth distribution, assuming a single column density value leads to a misleading interpretation of the source emission properties, nominall…
The Relation between Globular Cluster Systems and Supermassive Black Holes in Spiral Galaxies. III. The Link to the M •-M * Correlation
González-Lópezlira, Rosa A.; Gwyn, Stephen; Loinard, Laurent +6 more
We continue to explore the relationship between the total number of globular clusters (GCs), N GC, and the central black hole mass, M •, in spiral galaxies. We present here results for the Sab galaxies NGC 3368, NGC 4736 (M94), and NGC 4826 (M64), and the Sm galaxy NGC 4395. The GC candidate selection is based on the (u* - $i…
Observation and origin of non-thermal hard X-rays from Jupiter
Mori, Kaya; Branduardi-Raymont, Graziella; Nynka, Melania +10 more
Electrons accelerated on Earth by a rich variety of wave-scattering or stochastic processes1,2 generate hard, non-thermal X-ray bremsstrahlung up to ~1 MeV (refs. 3,4) and power Earth's various types of aurorae. Although Jupiter's magnetic field is an order of magnitude larger than Earth's, space-based telescopes have previou…
Important stellar perturbers found during the StePPeD database update based on Gaia EDR3 data
Dybczyński, Piotr A.; Berski, Filip; Tokarek, Jakub +3 more
Context. In 2020, the initial version of the Stellar Potential Perturbers Database (StePPeD) was presented with the aim to deliver up-to-date information on the stars and stellar systems that may perturb a long-period comet motion. We used the minimal distance between a star and the Sun as a selecting tool when compiling a list of interesting obje…
Extra-tidal star candidates in globular clusters of the Sagittarius dwarf spheroidal galaxy
Carballo-Bello, Julio A.; Minniti, Dante; Fernández-Trincado, José G. +4 more
Context. Globular clusters (GCs) associated with the Sagittarius dwarf spheroidal galaxy (Sgr dSph) have evolved under the gravitational potential of both Sgr dSph and the Milky Way. The effects of these potentials are most pronounced in the extra-tidal regions as compared to the central regions of the GCs.
Aims: We aim to study the extra-tid…
Radio emission in a nearby, ultra-cool dwarf binary: A multifrequency study
Rebolo, R.; Béjar, V. J. S.; Zapatero Osorio, M. R. +8 more
Context. The substellar triple system VHS J125601.92−125723.9 (hereafter VHS 1256−1257) is composed of an equal-mass M7.5 brown dwarf binary and an L7 low-mass substellar object. In Guirado et al. (2018, A&A, 610, A23) we published the detection of radio emission at 8.4 GHz coming from the central binary and making it an excellent target for f…
The five largest satellites of Uranus: Astrometric observations spread over 29 years at the Pico dos Dias Observatory
Fienga, A.; Assafin, M.; Camargo, J. I. B. +2 more
We present the astrometry of the five largest satellites of Uranus from observations spread over almost three decades with photographic plates and CCDs (mainly), taken at the Pico dos Dias Observatory - Brazil. All positions presented here are obtained from the reanalysis of measurements and images used in previous publications. Reference stars ar…
Evolution of coronal hole solar wind in the inner heliosphere: Combined observations by Solar Orbiter and Parker Solar Probe
Perri, S.; Lavraud, B.; Maksimovic, M. +18 more
We study the radial evolution, from 0.1 AU to the Earth, of a homogeneous recurrent fast wind, coming from the same source on the Sun, by means of new measurements by both Solar Orbiter and Parker Solar Probe. With respect to previous radial studies, we extend, for the first time, the analysis of a recurrent fast stream at distances never reached …
WD 1145+017: Alternative models of the atmosphere, dust clouds, and gas rings
Budaj, J.; Hubeny, I.; Maliuk, A.
Context. WD 1145+017 (WD1145) is the first white dwarf known to be orbited by disintegrating exoasteroids. It is a DBZ-type white dwarf with strongly variable broad circumstellar lines and variable shallow ultraviolet (UV) transits. Various models of the dust clouds and gaseous rings have been proposed as an explanation for this behavior.
Aim…