Search Publications
HD 85567: A Herbig B[e] star or an interacting B[e] binary?. Resolving HD 85567's circumstellar environment with the VLTI and AMBER
Weigelt, G.; Caratti o Garatti, A.; Wheelwright, H. E. +1 more
Context.
Aims: To elucidate the…
Comparison of solar horizontal velocity fields from SDO/HMI and Hinode data
Roudier, Th.; Malherbe, J. M.; Gizon, L. +7 more
Context. The measurement of the Sun's surface motions with a high spatial and temporal resolution is still a challenge.
Aims: We wish to validate horizontal velocity measurements all over the visible disk of the Sun from Solar Dynamics Observatory/ Helioseismic and Magnetic Imager (SDO/HMI) data.
Methods: Horizontal velocity fields are m…
Ultraviolet diagnostic of porosity-free mass-loss estimates in B stars
Prinja, R. K.; Massa, D. L.
Aims: We seek to establish evidence in UV P Cygni line profiles that the signs of wind clumping and porosity vary with velocity. We aim to demonstrate empirically that while at most wind velocities optically thick clumps cover only a fraction of the stellar surface, close to the terminal velocity (v∞) where narrow absorption compon…
Distribution of HNCO 505-404 in massive star-forming regions
Wang, J. Z.; Li, J.; Gu, Q. S. +1 more
Aims: The goal of this paper is to study the spatial distribution of HNCO in massive star-forming region and to investigate both its spatial association with infrared sources and physical conditions in region of HNCO emission.
Methods: We mapped nine massive star-forming regions in HNCO 505-404 with the Purple Mount…
The star formation history of the Sculptor dwarf irregular galaxy
Cole, A. A.; Lianou, S.
Aims: We study the resolved stellar populations and derive the star formation history of the Sculptor dwarf irregular galaxy (SDIG), a gas-rich dwarf galaxy member of the NGC 7793 subgroup in the Sculptor group of galaxies.
Methods: We constructed a colour - magnitude diagram (CMD) using archival observations from the Hubble Space Telesc…
Inferring the magnetic field vector in the quiet Sun. III. Disk variation of the Stokes profiles and isotropism of the magnetic field
Borrero, J. M.; Kobel, P.
Recent investigations of the magnetic field vector properties in the solar internetwork have provided diverging results. While some works found that the internetwork is mostly pervaded by horizontal magnetic fields, other works argued in favor of an isotropic distribution of the magnetic field vector. Motivated by these seemingly contradictory res…
HD 45314: a new γ Cassiopeiae analog among Oe stars
Morel, T.; Nazé, Y.; Rauw, G. +2 more
Context. Oe stars possibly form an extension to higher temperatures of the Be phenomenon, but it is still unclear whether these stars have disks.
Aims: X-ray spectra could provide hints for interactions of the star with a putative surrounding disk.
Methods: We obtained XMM-Newton observations of two Oe stars, HD 45314 and HD 60848. Spect…
X-ray emission regimes and rotation sequences in M 35 . An updated model of stellar activity evolution on the main sequence
Gondoin, P.
Context. Late-type stars in young open clusters show two kinds of dependence of their X-ray emission on rotation. They also tend to group into two main sub-populations that lie on narrow sequences in diagrams where their rotation periods are plotted against their (B - V) colour indices. A correlation between these two regimes of X-ray emission and…
X-ray properties of the young open clusters HM1 and IC 2944/2948
Corcoran, M. F.; Nazé, Y.; Rauw, G. +1 more
Using XMM-Newton data, we study for the first time the X-ray emission of HM1 and IC 2944/2948. Low-mass, pre-main-sequence objects with an age of a few Myr are detected, as well as a few background or foreground objects. Most massive stars in both clusters display the usual high-energy properties of that type of objects, though with log [LX
Transiting exoplanets from the CoRoT space mission. XXIV. CoRoT-25b and CoRoT-26b: two low-density giant planets
Mazeh, T.; Aigrain, S.; Alonso, R. +47 more
We report the discovery of two transiting exoplanets, CoRoT-25b and CoRoT-26b, both of low density, one of which is in the Saturn mass-regime. For each star, ground-based complementary observations through optical photometry and radial velocity measurements secured the planetary nature of the transiting body and allowed us to fully characterize th…