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The study of the early phases of star and planet formation is important to understand the physical and chemical history of stellar systems such as our own. In particular, protostars born in rich clusters are prototypes of the young Solar System. In the framework of the Seeds Of Life In Space (SOLIS) large observational project, the aim of the present work is to investigate the origin of the previously inferred high flux of energetic particles in the protocluster FIR4 of the Orion Molecular Cloud 2 (OMC-2), which appears asymmetric within the protocluster itself. Interferometric observations carried out with the IRAM NOEMA interferometer were used to map the silicon monoxide (SiO) emission around the FIR4 protocluster. Complementary archival data from the ALMA interferometer were also employed to help constrain excitation conditions. A physical-chemical model was implemented to characterise the particle acceleration along the protostellar jet candidate, along with a non-LTE analysis of the SiO emission along the jet. The emission morphology of the SiO rotational transitions hints for the first time at the presence of a collimated jet originating very close to the brightest protostar in the cluster, HOPS-108. The NOEMA observations unveiled a possible jet in the OMC-2 FIR4 protocluster propagating towards a previously measured enhanced cosmic-ray ionisation rate. This suggests that energetic particle acceleration by the jet shock close to the protostar might be at the origin of the enhanced cosmic-ray ionisation rate, as confirmed by modelling the protostellar jet., 8 pages, 7 figures, accepted for publications in A&A

We report the detection in space of a new molecular species which has been characterized spectroscopically and fully identified from astrophysical data. The observations were carried out with the 30m IRAM telescopea. The molecule is ubiquitous as its J=2→1 transition has been found in cold molecular clouds, prestellar cores, and shocks. However, it is not found in the hot cores of Orion-KL and in the carbon-rich evolved star IRC+10216. Three rotational transitions in perfect harmonic relation J′ = 2/3/5 have been identified in the prestellar core B1b. The molecule has a 1Σ electronic ground state and its J=2→1 transition presents the hyperfine structure characteristic of a molecule containing a nucleus with spin 1. A careful analysis of possible carriers shows that the best candidate is NS+. The derived rotational constant agrees within 0.3-0.7% with ab initio calculations. NS+ was also produced in the laboratory to unambiguously validate the astrophysical assignment. The observed rotational frequencies and determined molecular constants confirm the discovery of the nitrogen sulfide cation in space.

In 2006, the French Food Safety Agency (AFSSA) started the second French Total Diet Study to assess exposure to essential and non-essential elements through dietary intake by analysing 1352 food samples. A total of 21 elements were analysed to date by Inductively Coupled Plasma Mass Spectrometry after closed vessel microwave digestion, in 660 samples corresponding to at half of the study. This work presents and discusses the results of the various internal quality controls (IQC) applied to ensure that the analytical procedure is correctly carried out, from digestion to analysis, and to enable analytical chemists to validate the results obtained. The whole IQC allows to estimate uncertainties according to elements and to select those that should be discarded from the study or only given as indicative values for elements that were not within defined quality limits.

High spectral resolution Fabry-P erot observations of the [O I] 63.2 and 145.5 ma nd [CII] 157.7 m ne structure lines are presented for the center of the Sagittarius B2 complex (Sgr B2). The data were obtained with the Long Wavelength Spectrometer on board the Infrared Space Observatory (ISO).

Objectifs Realiser le bilan preoperatoire des enfants atteints de tetralogie de Fallot par realisation d’un scanner tout en maitrisant la dose d’irradiation par l’utilisation du mode sequentiel en scanner mulicoupe. Materiels et methodes L’etude porte sur une serie prospective de 38 jeunes patients qui ont ete operes d’une tetralogie de Fallot dans notre institution entre juillet 2007 et fevrier 2009. Les examens preoperatoires ont ete realises apres injection de contraste iode, en mode sequentiel, en adaptant les parametres d’acquisition au poids de l’enfant. Resultats L’evaluation morphologique a porte sur l’arbre arteriel pulmonaire, l’origine et le trajet des arteres coronaires, l’etude des malformations associees eventuelles (retours veineux pulmonaires et systemiques, arche aortique, compression bronchique). Trois anomalies d’origine des coronaires ont ete detectees, et diverses anomalies associees ont ete mises en evidence. Ces donnees ont ete confrontees aux constats per-operatoires. Conclusion Le scanner multicoupe en mode sequentiel permet de realiser, a moindre irradiation, une evaluation exhaustive des gros vaissaeux et des coronaires dans le bilan preoperatoire du Fallot avec une precision diagnostique elevee qui permet de surseoir a l’angiographie et de proposer un examen peu invasif compte tenu d’une irradiation diminuee.