Indépendance conditionnelle et uniformité pour les lois fortes des grands nombres dans les espaces de Banach

Summary A. Beck has given an uniform strong law of large numbers for families of mutually symmetric and uniformly essentially bounded sequences of centered random variables, with values in (k, )—B-convex spaces. We show that, without any limitation on the Banach spaces, the technique used by A. Beck allows to replace, in strong law of large numbers making use of conditions bearing on essential bounds, the hypothesis of independence by an hypothesis called conditional-independence-and-centering, which is weaker than both hypothesis of independence and of mutual symmetry; moreover, in several cases, one gets uniform strong laws of large numbers (for families of conditionally-independent-and-centered sequences). The results we get are compared with recent results of G. Pisier, obtained with type p spaces techniques.     

Ultrashort, intense ultraviolet pulse generation by efficient frequency tripling and adapted phase matching

We demonstrate efficient frequency tripling of 1057-chirped pulses, using adapted chirping and thick KDP crystals. These millijoules broadband pulses at 352 nm have been compressed to 220-fs duration by use of a UV grating-pair compressor. The technique is scalable to kilojoule petatwatt lasers.     

Die Methoden zur direkten Messung des osmotischen Drucks

Ohne Zusammenfassung     

Den Gefrierpunkt verschiedener Mischungen von Alkohol und Wasser

Ohne Zusammenfassung     

Sur la convergence de Césaro des familles de mesures

Sans résumé     

Potential energy and dipole moment surfaces of HCO- for the search of H- in the interstellar medium

Potential energy and permanent dipole moment surfaces of the electronic ground state of formyl negative ion HCO(-) are determined for a large number of geometries using the coupled-cluster theory with single and double and perturbative treatment of triple excitations ab initio method with a large basis set. The obtained data are used to construct interpolated surfaces, which are extended analytically to the region of large separations between CO and H(-) with the multipole expansion approach. We have calculated the energy of the lowest rovibrational levels of HCO(-) that should guide the spectroscopic characterization of HCO(-) in laboratory experiments. The study can also help to detect HCO(-) in the cold and dense regions of the interstellar medium where the anion could be formed through the association of abundant CO with still unobserved H(-).     

Determination of the ESR parameters of Cu2+ doped in CdC4H4O6 · 5H2O single crystals using a statistical calculation technique

Electron spin resonance spectra of Cu²⁺-doped cadmium tartrate pentahydrate single crystals grown by the diffusion technique have been investigated at 77 K. Two magnetically inequivalent Cu²⁺ lattice sites were identified. For each site four hyperfine lines and some additional weak forbidden hyperfine lines due to the quadrupole interaction were observed. The spectra were analyzed by a perfect least-squares procedure based on an appropriate statistical model to determine the spin-Hamiltonian parameters.     

Efficient generation of narrow-bandwidth picosecond pulses by frequency doubling of femtosecond chirped pulses

We demonstrate efficient generation of picosecond narrow-bandwidth pulses by frequency mixing of broadband opposite chirped pulses in a type I doubling crystal. This procedure allows us to produce picosecond pulses that are perfectly synchronized with femtosecond pulses. The experiment shows a decrease of the initial bandwidth by a factor of more than 30, while a high conversion efficiency is maintained.