Search Publications
On X-ray pulsations in β Cephei-type variables
Hamann, W. -R.; Hubrig, S.; Oskinova, L. M. +4 more
Context. β Cep-type variables are early B-type stars that are characterized by oscillations observable in their optical light curves. At least one β Cep-variable also shows periodic variability in X-rays.
Aims: Here we study the X-ray light curves in a sample of β Cep-variables to investigate how common X-ray pulsations are for this type of s…
Observations of water with Herschel/HIFI toward the high-mass protostar AFGL 2591
van Dishoeck, E. F.; van der Tak, F. F. S.; Wyrowski, F. +2 more
Context. Water is an important chemical species in the process of star formation, and a sensitive tracer of physical conditions in star-forming regions because of its rich line spectrum and large abundance variations between hot and cold regions.
Aims: We use spectrally resolved observations of rotational lines of H2O and its isoto…
The spectral energy distribution of galaxies at z > 2.5: Implications from the Herschel/SPIRE color-color diagram
Buat, Véronique; Burgarella, Denis; Hou, Jinliang +5 more
We use the Herschel SPIRE color-color diagram to study the spectral energy distribution (SED) and the redshift estimation of high-z galaxies. We compiled a sample of 57 galaxies with spectroscopically confirmed redshifts and SPIRE detections in all three bands at z = 2.5-6.4, and compared their average SPIRE colors with SED templates from local an…
3D hydrodynamic simulations of the Galactic supernova remnant CTB 109
Sasaki, M.; Breitschwerdt, D.; Bolte, J.
Context. Using detailed 3D hydrodynamic simulations we study the nature of the Galactic supernova remnant (SNR)
Aims: Our model has been designed to explain the observed morphology, with a special…
Molecular gas and nuclear activity in early-type galaxies: any link with radio loudness?
Kuno, Nario; Capetti, Alessandro; Baldi, Ranieri D. +4 more
Aims: We want to study the amount of molecular gas in a sample of nearby early-type galaxies (ETGs) that host low-luminosity active galactic nuclei (AGN). We look for possible differences between the radio-loud (RL) and radio-quiet (RQ) AGN.
Methods: We observed the CO(1-0) and CO(2-1) spectral lines with the IRAM 30 m and NRO 45 m teles…
The XMM Deep Survey in the CDF-S. VII. UV catalogue of the Optical Monitor observations
Talavera, A.; Vignali, C.; Ranalli, P. +5 more
Context. The XMM-Newton X-ray observatory has repeatedly observed the Chandra Deep Field-South (CDF-S) in 33 epochs (2001-2010) through the XMM-CDFS Deep Survey. During the X-ray observations, XMM-OM targeted the central 17 × 17 arcmin2 region of the X-ray field of view, providing simultaneous optical/UV coverage of the CDF-S. The resul…
Lower mass normalization of the stellar initial mass function for dense massive early-type galaxies at z ~ 1.4
Longhetti, M.; Gargiulo, A.; Saracco, P. +3 more
Aims: This paper aims at understanding whether the normalization of the stellar initial mass function (IMF) of massive galaxies varies with cosmic time and/or with mean stellar mass density Σ = M⋆/(2πRe2).
Methods: We have tackled this question by taking advantage of a spectroscopic sample of 18 dense (Σ …
Herschel-PACS observations of [OI] and H2O in Chamaeleon II
Duchêne, G.; Dent, W. R. F.; Kamp, I. +11 more
Context. Gas plays a major role in the dynamical evolution of protoplanetary discs. Its coupling with the dust is the key to our understanding of planetary formation. Studying the gas content is therefore a crucial step towards understanding protoplanetary discs evolution. Such a study can be made through spectroscopic observations of emission lin…
New view on exoplanet transits. Transit of Venus described using three-dimensional solar atmosphere STAGGER-grid simulations
Tanga, P.; Chiavassa, A.; Asplund, M. +5 more
Context. An important benchmark for current observational techniques and theoretical modeling of exoplanet atmospheres is the transit of Venus (ToV). Stellar activity and, in particular, convection-related surface structures, potentially cause fluctuations that can affect the transit light curves. Surface convection simulations can help interpreti…
Coronae of stars with supersolar elemental abundances
Behar, Ehud; Peretz, Uria; Drake, Stephen A.
Coronal elemental abundances are known to deviate from the photospheric values of their parent star, with the degree of deviation depending on the first ionization potential (FIP). This study focuses on the coronal composition of stars with supersolar photospheric abundances. We present the coronal abundances of six such stars: 11 LMi, ι Hor, HR 7…