Search Publications

History of Mars Atmosphere Observations

Christensen, Philip R.; Lemmon, Mark T.; Withers, Paul +2 more

CCD astrometric observations of Amalthea and Thebe in the Gaia era

Colas, F.; Saquet, E.; Robert, V. +1 more

In the framework of the 2014-2015 campaign of mutual events, we observed Jupiter's inner satellites Amalthea (JV) and Thebe (JXIV). We focused on estimating whether the positioning accuracy determined from direct astrometry could compete with that derived from photometric observations of eclipses, for dynamical purposes. We present the analysis of…

Comparison of Gaia and asteroseismic distances

Roth, M.; Örtel, S.; Yıldız, M. +1 more

Asteroseismology provides fundamental properties (mass, radius and effective temperature) of solar-like oscillating stars using so-called scaling relations. These properties allow the computation of the asteroseismic distance of stars. We compare the asteroseismic distances with the recently released Gaia distances for 74 stars studied in Yıldız e…

Computation of the Transmitted and Polarized Scattered Fluxes by the Exoplanet HD 189733b in X-Rays

Marin, Frédéric; Grosso, Nicolas

Thousands of exoplanets have been detected, but only one exoplanetary transit was potentially observed in X-rays from HD 189733A. What makes the detection of exoplanets so difficult in this band? To answer this question, we run Monte-Carlo radiative transfer simulations to estimate the amount of X-ray flux reprocessed by HD 189733b. Despite its ex…

Multi-spacecraft studies of the auroral acceleration region: From cluster to nanosatellites

Sadeghi, S.; Emami, M. R.

This paper discusses the utilization of multiple Cubesats in various formations for studies in the auroral acceleration region. The focus is on the quasi-static properties, spatio-temporal features, electric potential structures, field-aligned currents, and their relationships, all of which are fundamentally important for an understanding of the m…

Far Ultraviolet Spectroscopy of Old Novae. II. RR Pic, V533 Her, and DI Lac

Sion, Edward M.; Godon, Patrick; Jones, Liam

The old novae V533 Her (Nova Her 1963), DI Lac (Nova Lac 1910), and RR Pic (Nova Pic 1891) are in (or near) their quiescent stage, following their nova explosions, and continue to accrete at a high rate in the aftermath of their explosions. They exhibit continua that are steeply rising into the FUV, as well as absorption lines and emission lines o…

A TGAS/Gaia DR1 parallactic distance to the σ Orionis cluster

Caballero, José A.

With the new Tycho-Gaia Astrometric Solution (TGAS), I derive a new parallactic distance to the young σ Orionis open cluster, which is a cornerstone region for studying the formation and evolution of stars and substellar objects from tens of solar masses to a few Jupiter masses. I started with the list of the 46 brightest cluster stars of Caballer…

Suzaku and Chandra observations of the galaxy cluster RXC J1053.7+5453 with a radio relic

Fukazawa, Yasushi; Nakazawa, Kazuhiro; Ohashi, Takaya +10 more

We present the results of Suzaku and Chandra observations of the galaxy cluster RXC J1053.7+5453 (z = 0.0704), which contains a radio relic. The radio relic is located at a distance of ∼540 kpc from the X-ray peak toward the west. We measured the temperature of this cluster for the first time. The resultant temperature in the center is ∼1.3 keV, w…

The Integrated Cluster Finder for the ARCHES project

Schwope, Axel; Mints, Alexey; Rosen, Simon +2 more

Context. Clusters of galaxies are important for cosmology and astrophysics. They may be discovered through either the summed optical/IR radiation originating from their member galaxies or via X-ray emission originating from the hot intracluster medium. X-ray samples are not affected by projection effects but a redshift determination typically need…

Wind asymmetry imprint in the UV light curves of the symbiotic binary SY Mus

Skopal, A.; Shagatova, N.

Context. Light curves (LCs) of some symbiotic stars show a different slope of the ascending and descending branch of their minimum profile. The origin of this asymmetry is not well understood.
Aims: We explain this effect in the ultraviolet LCs of the symbiotic binary SY Mus.
Methods: We model the continuum fluxes in the spectra obtained…