HD 209458: Physical Parameters of the Parent Star and the Transiting Planet

The Sun-like star HD209458 harbors a close-in giant planet which transits across the star's disk, and thus allows an unprecedented access to the basic parameters of the planet, given a certain knowledge of the basic parameters of the star, namely its mass and radius. We present theoretical stellar evolution model calculations for HD 209458 and discuss the uncertainties involved in deriving the stellar mass and radius. We derive the mass, M=1.06 Msun, radius, R=1.18 Rsun,and age, t=5.2 Gyr of the star with uncertainties of 10% or more. The dominant sources of uncertainty remain to be the helium abundance estimate and the treatment of convection, even after an optimistic estimate for the effective temperature of the star. However, we find that in deriving the radius of the planet, R_p, the relevant stellar model input is the M/R relation, which runs orthogonal to a degeneracy in the transit light curve solution and greatly improves the estimate of R_p. Theoretically the M/R relation has a lower uncertainty than the M and R separately. We estimate the planet radius and mass to be R_p =1.42 +0.10/-0.13 R_J and M_p =0.69 +/- 0.02 M_J.Comment: 24 pages, 5 figures, accepted by the Astrophysical Journal; added correct version of figure 5 and fixed reference

Management of EPICS IOCs in a Distributed Network Environment Using Salt

An EPICS-based control system typically consists of many individual IOCs, which can be distributed across many computers in a network. Managing hundreds of deployed IOCs, keeping track of where they are running, and providing operators with basic interaction capabilities can easily become a maintenance nightmare. At the Institute for Beam Physics and Technology (IBPT) of the Karlsruhe Institute of Technology (KIT), we operate separate networks for our accelerators KARA and FLUTE and use the Salt Project to manage the IT infrastructure. Custom Salt states take care of deploying our IOCs across multiple servers directly from the code repositories, integrating them into the host operating system and monitoring infrastructure. In addition, this allows the integration into our GUI in order to enable operators to monitor and control the process for each IOC without requiring any specific knowledge of where and how that IOC is deployed. Therefore, we can maintain and scale to any number of IOCs on any numbers of hosts nearly effortless. This paper presents the design of this system, discusses the tools and overall setup required to make it work, and shows off the integration into our GUI and monitoring systems

Lire Monique Wittig aujourd’hui

Monique Wittig fut à la fois l'auteur d'une œuvre romanesque importante, une militante engagée dès l'origine dans le mouvement de libération des femmes, et une théoricienne prônant un féminisme matérialiste qui remet en cause, à partir du point de vue lesbien, « la pensée straight ». Reconnu et étudié depuis longtemps déjà à l'étranger, et notamment aux États-Unis où elle a vécu, son travail d'écriture, inextricablement lié à une activité militante et à une exigence théorique, restait à approfondir en France. Lire Monique Wittig, c'est interroger les rapports entre façons d'écrire, façons de parler et façons d'agir, tels qu'ils se manifestent dans ses textes mêmes : c'est ce que propose ce livre, qui réunit des contributions d'universitaires issues de différents champs disciplinaires, de militant.e.s, d'écrivain.e.s. Pour qui en effet se refuse à penser que la littérature appartienne aux arts décoratifs, pour qui pense qu'au contraire peuvent s'élaborer dans l'écriture des pratiques susceptibles d'être réappropriées et que le travail sur le langage est le lieu même où peuvent se former une pensée et une politique, alors Lire Monique Wittig aujourd'hui s'impose