Search Publications
Probing changes of dust properties along a chain of solar-type prestellar and protostellar cores in Taurus with NIKA
Adam, R.; Benoît, A.; Catalano, A. +45 more
The characterization of dust properties in the interstellar medium is key for understanding the physics and chemistry of star formation. Mass estimates are crucial to determine gravitational collapse conditions for the birth of new stellar objects in molecular clouds. However, most of these estimates rely on dust models that need further observati…
The HIP 79977 debris disk in polarized light
Ménard, F.; Quanz, S. P.; Siebenmorgen, R. +40 more
Context. Debris disks are observed around 10 to 20% of FGK main-sequence stars as infrared excess emission. They are important signposts for the presence of colliding planetesimals and therefore provide important information about the evolution of planetary systems. Direct imaging of such disks reveals their geometric structure and constrains thei…
A long-term study of AGN X-ray variability . Structure function analysis on a ROSAT-XMM quasar sample
Bianchi, S.; Paolillo, M.; Middei, R. +3 more
Context. Variability in the X-rays is a key ingredient in understanding and unveiling active galactic nuclei (AGN) properties. In this band, flux variations occur on short timescales (hours) as well as on larger timescales. While short timescale variability is often investigated in single source studies, only a few works are able to explore flux v…
Testing giant planet formation in the transitional disk of SAO 206462 using deep VLT/SPHERE imaging
Quanz, S. P.; Henning, T.; Ginski, C. +42 more
Context. The SAO 206462 (HD 135344B) disk is one of the few known transitional disks showing asymmetric features in scattered light and thermal emission. Near-infrared scattered-light images revealed two bright outer spiral arms and an inner cavity depleted in dust. Giant protoplanets have been proposed to account for the disk morphology.
Aim…
MASCARA-1 b. A hot Jupiter transiting a bright mV = 8.3 A-star in a misaligned orbit
Snellen, I. A. G.; Grundahl, F.; Albrecht, S. +11 more
We report the discovery of MASCARA-1 b, which is the first exoplanet discovered with the Multi-site All-Sky CAmeRA (MASCARA). This exoplanet is a hot Jupiter orbiting a bright mV = 8.3, rapidly rotating (vsini⋆ > 100 km s-1) A8 star with a period of 2.148780 ± 8 × 10-6 days. The planet has a mass and …
Modelling clumpy photon-dominated regions in 3D. Understanding the Orion Bar stratification
Röllig, M.; Ossenkopf-Okada, V.; Andree-Labsch, S.
Context. Models of photon-dominated regions (PDRs) still fail to fully reproduce some of the observed properties. In particular they do not reproduce the combination of the intensities of different PDR cooling lines together with the chemical stratification, as observed for example for the Orion Bar PDR.
Aims: We aim to construct a numerical …
Improvement of solar-cycle prediction: Plateau of solar axial dipole moment
Kusano, K.; Shiota, D.; Imada, S. +2 more
Aims: We report the small temporal variation of the axial dipole moment near the solar minimum and its application to the solar-cycle prediction by the surface flux transport (SFT) model.
Methods: We measure the axial dipole moment using the photospheric synoptic magnetogram observed by the Wilcox Solar Observatory (WSO), the ESA/NASA So…
CHEERS: The chemical evolution RGS sample
Zhang, Y. -Y.; Finoguenov, A.; Böhringer, H. +17 more
Context. The chemical yields of supernovae and the metal enrichment of the intra-cluster medium (ICM) are not well understood. The hot gas in clusters of galaxies has been enriched with metals originating from billions of supernovae and provides a fair sample of large-scale metal enrichment in the Universe. High-resolution X-ray spectra of cluster…
Resolved astrometric orbits of ten O-type binaries
Absil, O.; Ertel, S.; Grellmann, R. +11 more
Aims: Our long-term aim is to derive model-independent stellar masses and distances for long period massive binaries by combining apparent astrometric orbit with double-lined radial velocity amplitudes (SB2).
Methods: We followed-up ten O+O binaries with AMBER, PIONIER and GRAVITY at the VLTI. Here, we report on 130 astrometric observati…
Deuteration of ammonia in the starless core Ophiuchus/H-MM1
Daniel, F.; Schlemmer, S.; Güsten, R. +13 more
Context. Ammonia and its deuterated isotopologues probe physical conditions in dense molecular cloud cores. The time-dependence of deuterium fractionation and the relative abundances of different nuclear spin modifications are supposed to provide a means of determining the evolutionary stages of these objects.
Aims: We aim to test the current…