On the nature of the Herbig B[e] star binary system V921 Scorpii: Geometry and kinematics of the circumprimary disk on sub-AU scales

V921 Scorpii is a close binary system (separation 0.025") showing the B[e]-phenomenon. The system is surrounded by an enigmatic bipolar nebula, which might have been shaped by episodic mass-loss events, possibly triggered by dynamical interactions between the companion and the circumprimary disk (Kraus et al. 2012a). In this paper, we investigate the spatial structure and kinematics of the circumprimary disk, with the aim to obtain new insights into the still strongly debated evolutionary stage. For this purpose, we combine, for the first time, infrared spectro-interferometry (VLTI/AMBER, R=12,000) and spectro-astrometry (VLT/CRIRES, R=100,000), which allows us to study the AU-scale distribution of circumstellar gas and dust with an unprecedented velocity resolution of 3 km*s^-1. Using a model-independent photocenter analysis technique, we find that the Br-gamma-line emission rotates in the same plane as the dust disk. We can reproduce the wavelength-differential visibilities and phases and the double-peaked line profile using a Keplerian-rotating disk model. The derived mass of the central star is 5.4+/-0.4 M_sun*(d/1150 pc), which is considerably lower than expected from the spectral classification, suggesting that V921 Sco might be more distant (d approx 2kpc) than commonly assumed. Using the geometric information provided by our Br-gamma spectro-interferometric data and Paschen, Brackett, and Pfund line decrement measurements in 61 hydrogen recombination line transitions, we derive the density of the line-emitting gas (N_e=2...6*10^19 m^-3). Given that our measurements can be reproduced with a Keplerian velocity field without outflowing velocity component and the non-detection of age-indicating spectroscopic diagnostics, our study provides new evidence for the pre-main-sequence nature of V921 Sco.Comment: 17 pages, 11 figures, 3 tables, accepted by Ap

Commentaires sur la Théorie Psychanalytique du Moi

Dès les années 1900, et même avant que son intérêt se soit définitivement porté de la théorie physiologique à la théorie psychologique, Freudparle d'un Moi, en partie dans un sens qui fait présagernettement les développements ultérieurs de la psychologie du Moi. Cependant, l'élaboration plus approfondie de cette partie de son travail a dû être retardée pendant une période au cours de laquelle sa préoccupation principale était le développement d'autres aspects de la psychanalyse. Tous les travaux révolutionnaires de ces années approchent la personnalité en passant par ce que nous appellerions aujourd'hui l'étude du Ça. Ainsi, dans l'analyse, une base importante de faits et d'hypothèses a été établie — sur les lois gouvernant les processus mentaux inconscients, sur les caractéristiqueset le développementdes pulsions instinctuelles, et sur certains aspects du conflit psychique — dont l'absence avait été un grave handicap pour la psychologie préanalytique. Le fait que l'étude du Ça par Freud a précédé son approche de la psychologie structurale est en vérité un des événements les plus importants dans l'histoire de la psychologie

DINI-Zertifikat 2013 - Request for Comments

Das wissenschaftliche Publikationswesen ist ein wesentlicher Stützpfeiler des wissenschaftlichen Erkenntnisfortschritts und der Wissenschaft insgesamt. Zu seinen Kennzeichen gehören (a) die Organisation einer effektiven Kommunikation zwischen Wissenschaftler/-innen (i.e. zwischen Autor/-innen und allen potentiellen Rezipient/-innen, d.h. die Sicherstellung einer adäquaten Verbreitung), (b) ein hohes Maß an Vertrauenswürdigkeit, das den Nutzer/-innen des Publikationswesens (i.e. den Wissenschaftler/-innen) vermittelt wird (z.B. in Bezug auf das Prioritätsrecht, die Wahrung des Urheberrechts sowie die Authentizität und die inhaltliche Qualität wissenschaftlicher Arbeiten), (c) Nachhaltigkeit und Nachprüfbarkeit (dauerhafte Zitierbarkeit und langfristige Verfügbarkeit, Nachvollziehbarkeit von einzelnen Schritten auf dem Weg zur Veröffentlichung). Mit dem vorliegenden Kriterienkatalog, der dem DINI-Zertifikat zugrunde liegt, werden diese allgemeinen Erwartungen an das wissenschaftliche Publizieren in konkrete Mindestanforderungen übersetzt, die an Open-Access-Repositorien und -Publikationsdienste zu stellen sind. Sie bilden als Plattformen für die Veröffentlichung und Bereitstellung wissenschaftlicher Publikationen in elektronischer Form wichtige Knotenpunkte für den wissenschaftlichen Kommunikationsprozess und tragen als Open-Access-Dienste zur Verbreitung und Demokratisierung von Wissen bei

Low-Tg phosphate glasses with improved water resistance for the coating of fluoride glass fibers

Starting from a multicomponent lead phosphate glass composition given in the literature, a glass was developed suitable for the protective overclad of heavy-metal fluoride glass fibers. Besides a low glass transition temperature 18 * 10⁻⁶ K⁻¹ the phosphate glass material developed had a water resistance at 60°C for 10 h comparable to that of commercial container glass. The final composition developed was (in mol%): 54.7 P₂O₅, 19.8 PbO, 18.0 Na₂O, 1.2 MgO, 1.2 BaO, 1.2 CaO, 0.4 V₂O₅, 1.5 AI₂O₃, 2.0 Bi₂O₃. Besides the influences of these different components the acdon of the melting conditions, especially melting temperature and trace SiO₂ content from the crucible material, have to be taken into account. Fiber drawing experiments including the in-situ apphcation of the phosphate glass overclad were successful

Observation of Scaling Violations in Scaled Momentum Distributions at HERA

Charged particle production has been measured in deep inelastic scattering (DIS) events over a large range of $x$ and $Q^2$ using the ZEUS detector. The evolution of the scaled momentum, $x_p$, with $Q^2,$ in the range 10 to 1280 $GeV^2$, has been investigated in the current fragmentation region of the Breit frame. The results show clear evidence, in a single experiment, for scaling violations in scaled momenta as a function of $Q^2$.Comment: 21 pages including 4 figures, to be published in Physics Letters B. Two references adde

Accretion, Outflows, and Winds of Magnetized Stars

Many types of stars have strong magnetic fields that can dynamically influence the flow of circumstellar matter. In stars with accretion disks, the stellar magnetic field can truncate the inner disk and determine the paths that matter can take to flow onto the star. These paths are different in stars with different magnetospheres and periods of rotation. External field lines of the magnetosphere may inflate and produce favorable conditions for outflows from the disk-magnetosphere boundary. Outflows can be particularly strong in the propeller regime, wherein a star rotates more rapidly than the inner disk. Outflows may also form at the disk-magnetosphere boundary of slowly rotating stars, if the magnetosphere is compressed by the accreting matter. In isolated, strongly magnetized stars, the magnetic field can influence formation and/or propagation of stellar wind outflows. Winds from low-mass, solar-type stars may be either thermally or magnetically driven, while winds from massive, luminous O and B type stars are radiatively driven. In all of these cases, the magnetic field influences matter flow from the stars and determines many observational properties. In this chapter we review recent studies of accretion, outflows, and winds of magnetized stars with a focus on three main topics: (1) accretion onto magnetized stars; (2) outflows from the disk-magnetosphere boundary; and (3) winds from isolated massive magnetized stars. We show results obtained from global magnetohydrodynamic simulations and, in a number of cases compare global simulations with observations.Comment: 60 pages, 44 figure