Search Publications
C2H observations toward the Orion Bar
Ossenkopf, V.; Nagy, Z.; Bergin, E. A. +3 more
Context. The ethynyl radical (C2H) is one of the first radicals to be detected in the interstellar medium. Its higher rotational transitions have recently become available with the Herschel Space Observatory.
Aims: We aim to constrain the physical parameters of the C2H emitting gas toward the Orion Bar.
Methods: We …
CONSERT suggests a change in local properties of 67P/Churyumov-Gerasimenko's nucleus at depth
Lasue, J.; Plettemeier, D.; Kofman, W. +5 more
Context. After the successful landing of Philae on the nucleus of 67P/Churyumov-Gerasimenko, the Rosetta mission provided the first opportunity of performing measurements with the CONSERT tomographic radar in November 2014. CONSERT data were acquired during this first science sequence. They unambiguously showed that propagation through the smaller…
Simultaneous X-ray and optical spectroscopy of the Oef supergiant λ Cephei
Schmitt, J. H. M. M.; Gosset, E.; Nazé, Y. +8 more
Context. Probing the structures of stellar winds is of prime importance for the understanding of massive stars. Based on their optical spectral morphology and variability, it has been suggested that the stars in the Oef class feature large-scale structures in their wind.
Aims: High-resolution X-ray spectroscopy and time-series of X-ray observ…
Origin of the X-ray off-states in Vela X-1
Walter, R.; Manousakis, A.
Context. Vela X-1 is the prototype of the classical super-giant high mass X-ray binary systems. Recent continuous and long monitoring campaigns revealed a large hard X-rays variability amplitude with strong flares and off-states. This activity has been interpreted by invoking clumpy stellar winds and/or magnetic gating mechanisms.
Aims: We in…
Recurrent flares in active region NOAA 11283
Romoli, M.; Vecchio, A.; Pietropaolo, E. +21 more
Context. Flares and coronal mass ejections (CMEs) are solar phenomena that are not yet fully understood. Several investigations have been performed to single out their related physical parameters that can be used as indices of the magnetic complexity leading to their occurrence.
Aims: In order to shed light on the occurrence of recurrent flar…
Analysis of HST/COS spectra of the bare C-O stellar core H1504+65 and a high-velocity twin in the Galactic halo
Rauch, T.; Werner, K.
Recovering star formation histories: Integrated-light analyses vs. stellar colour-magnitude diagrams
Koleva, M.; Alloin, D.; Monelli, M. +12 more
Context. Accurate star formation histories (SFHs) of galaxies are fundamental for understanding the build-up of their stellar content. However, the most accurate SFHs - those obtained from colour-magnitude diagrams (CMDs) of resolved stars reaching the oldest main-sequence turnoffs (oMSTO) - are presently limited to a few systems in the Local Grou…
Missing cosmic metals revealed by X-ray absorption towards distant sources
Ferrara, Andrea; Pallottini, Andrea; Salvaterra, Ruben +1 more
The census of heavy elements (metals) produced by all stars through cosmic times up to present-day is limited to ≲ 50%; of these only half are still found within their parent galaxy. The majority of metals is expelled from galaxies into the circumgalactic (or even more distant, intergalactic) space by powerful galactic winds, leaving unpleasant un…
Dust attenuation up to z ≃ 2 in the AKARI North Ecliptic Pole Deep Field
Ciesla, L.; Buat, V.; Burgarella, D. +13 more
Aims: We aim to study the evolution of dust attenuation in galaxies selected in the infrared (IR) in the redshift range in which they are known to dominate the star formation activity in the universe. The comparison with other measurements of dust attenuation in samples selected using different criteria will give us a global picture of the at…
V444 Cygni X-ray and polarimetric variability: Radiative and Coriolis forces shape the wind collision region
Corcoran, M. F.; Russell, C. M. P.; Nazé, Y. +8 more
We present results from a study of the eclipsing, colliding-wind binary V444 Cyg that uses a combination of X-ray and optical spectropolarimetric methods to describe the 3D nature of the shock and wind structure within the system. We have created the most complete X-ray light curve of V444 Cyg to date using 40 ks of new data from Swift, and 200 ks…