Protoneutron stars within the Brueckner-Bethe-Goldstone theory

We study the structure of newly born neutron stars (protoneutron stars) within the finite temperature Brueckner-Bethe-Goldstone theoretical approach including also hyperons. We find that for purely nucleonic stars both finite temperature and neutrino trapping reduce the value of the maximum mass. For hyperonic stars the effect is reversed, because neutrino trapping shifts the appearance of hyperons to larger baryon density and stiffens considerably the equation of state.Comment: 11 pages, 7 figures, submitted to Astronomy & Astrophysic

Triton calculations with π\pi and ρ\rho exchange three-nucleon forces

The Faddeev equations are solved in momentum space for the trinucleon bound state with the new Tucson-Melbourne $\pi$ and $\rho$ exchange three-nucleon potentials. The three-nucleon potentials are combined with a variety of realistic two-nucleon potentials. The dependence of the triton binding energy on the $\pi NN$ cut-off parameter in the three-nucleon potentials is studied and found to be reduced compared to the case with pure $\pi$ exchange. The $\rho$ exchange parts of the three-nucleon potential yield an overall repulsive effect. When the recommended parameters are employed, the calculated triton binding energy turns out to be very close to its experimental value. Expectation values of various components of the three-nucleon potential are given to illustrate their significance for binding.Comment: 17 pages Revtex 3.0, 4 figures. Accepted for publication in Phys. Rev.

Momentum and Coordinate Space Three-nucleon Potentials

In this paper we give explicit formulae in momentum and coordinate space for the three-nucleon potentials due to $\rho$ and $\pi$ meson exchange, derived from off-mass-shell meson-nucleon scattering amplitudes which are constrained by the symmetries of QCD and by the experimental data. Those potentials have already been applied to nuclear matter calculations. Here we display additional terms which appear to be the most important for nuclear structure. The potentials are decomposed in a way that separates the contributions of different physical mechanisms involved in the meson-nucleon amplitudes. The same type of decomposition is presented for the $\pi - \pi$ TM force: the $\Delta$, the chiral symmetry breaking and the nucleon pair terms are isolated.Comment: LATEX, 33 pages, 3 figures (available as postscript files upon request

La pratique du rituel dans le temple égyptien

International audienceTemple is the place of the ritual. Rituals are of all kinds and performed to variable frequency. Next to the daily ritual made for feeding, adorning, or dressing divinities, we observe a whole set of rituals connected with specific events of the year, like the New Year (ritual of the disk Union for example), or conducted for special divinities / persons (ritual of the month of Khoiak's month, ritual of the confirmation of the royal power). These rituals are mainly known by textual sources on papyrus which were rarely discovered in context. They were textual versions of the ritual, more than manual for the priest. These written sources are completed with a plethoric iconographic documentation coming from temples and the material from the excavations. All these documentations (text, picture, material) must be taken into account and must be confronted with each other to obtain an idea, as complete as possible, of the ritual in temples and the way to perform it.Le temple est le lieu par excellence du rituel. Les rituels qui y sont pratiqués sont de toutes sortes et conduits à fréquence variable. À côté du rituel divin journalier per-mettant de nourrir, soigner, parer et habiller le dieu quoti-diennement, on observe tout un ensemble de rituels rat-tachés à des événements spécifiques de l'année comme le Nouvel An (rituel de l'Union au disque, rituel d'apaise-ment de Sekhmet) ou à des divinités/personnes particu-lières : rituel du mois de Khoïak pour régénérer Osiris, rituel de confirmation du pouvoir royal ou encore rituel de massacre des ennemis. Ces rituels sont principalement connus par des versions sur papyrus qui n'ont que rare-ment été découverts dans le contexte des temples et qui étaient d'abord des copies du texte rituel avant d'être des manuels de la conduite du rite. À ces sources écrites vien-nent s'ajouter une documentation iconographique plétho-rique figurant sur les temples et le matériel issu des fouilles. Ce sont autant de documents qui doivent être pris en compte et confrontés afin d'obtenir une vision aussi complète que possible de la conduite des rituels dans les temples

Géosciences, archéologie et histoire en Crète de l’Âge du Bronze récent à l’époque Archaïque

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