Themistius’ Paraphrase of Posterior Analytics 71a17-b8 : An Example of Rearrangement of an Aristotelian Text

L’auteur met en évidence la façon dont Thémistius, dans sa paraphrase, réorganise les parties du texte des lignes 71a17-b8 des Seconds Analytiques. Par une analyse détaillée du propos d’Aristote dans ces lignes, il montre que la réorganisation proposée par Thémistius est fidèle à l’esprit du texte aristotélicien, et s’appuie vraisemblablement sur des indices externes dont disposait le paraphraste.The author shows how Themistius, in his paraphrase, reorganizes the parts of Posterior Analytics 71a17-b8. Through a close analysis of Aristotle’s text, he demonstrates that this reorganization rests on a sound reading of Aristotle, and that, in all likelihood, it was prompted by external evidence that Themistius had at his disposal

Atmospheric lepton fluxes at very high energy

The observation of astrophysical neutrinos requires a detailed understanding of the atmospheric neutrino background. Since neutrinos are produced in meson decays together with a charged lepton, important constraints on this background can be obtained from the measurement of the atmospheric muon flux. Muons, however, can also be produced as mu+ mu- pairs by purely electromagnetic processes. We use the Z-moment method to study and compare the contributions to the atmospheric muon and neutrino fluxes from different sources (pi/K decay, charmed and unflavored hadron decay, and photon conversion into a muon pair). We pay special attention to the contribution from unflavored mesons (eta, eta', rho0, omega and phi). These mesons are abundant in air showers, their lifetimes are much shorter than those of charged pions or kaons, and they have decay branching ratios of order 10^-4 into final states containing a muon pair. We show that they may be the dominant source of muons at E_mu >10^3 TeV.Comment: Pdflatex, 28 pages, 6 figure

SUSY Spectrum and the Higgs Mass in the BLMSSM

The predictions for the mass of the light CP-even Higgs are investigated in the context of a simple extension of the Minimal Supersymmetric Standard Model where the baryon and lepton numbers are local gauge symmetries. This theory predicts the existence of light charged and neutral leptons which give extra contributions to the Higgs mass at the one-loop level. We show the possibility to satisfy the LEP2 bound and achieve a Higgs mass around 125 GeV in a supersymmetric spectrum with light sfermions and small left-right mixing in the stop sector. We make a brief discussion of the unique leptonic signals at the Large Hadron Collider. This theory predicts baryon number violation at the low scale and one could avoid the current LHC bounds on the supersymmetric mass spectrum.Comment: references added, minor corrections, to appear in Physics Letters