Search results for " Sam"
showing 10 items of 1096 documents
Half-lives, neutron emission probabilities and fission yields of neutron-rich rubidium isotopes in the mass regionA=96 toA=100
1979
Neutron-rich rubidium isotopes were produced by thermal-neutron induced fission of235U and were isolated by surface ionization and mass separation. The new isotope (51 ±17) ms100Rb was identified. The half-lives of the rubidium isotopes with mass numberA=96 toA=100 were measured using neutron multiscaling or gamma multispectrum analysis. Measurements of the delayed-neutron emission probabilityP n of99Rb and of the fission yields of97Rb,98Rb, and99Rb were performed.
New results on hyperon decays from NA48
2001
In 1999 the NA48 experiment at CERN had two short data taking periods (8h and 40h) with a high intensity KS beam. Together with the KS mesons a large number of neutral hyperons, e.g. Λ and Ξ0, are produced. During these periods a large sample of Ξ0 decays was collected. About 115,000 events of the decay mode Ξ0 → Λπ0, about 500 of Ξ0 → Λγ, about 400 of Ξ0 → Σ0γ and about 60 events of Ξ0 → Σ+ e have been reconstructed. The status of the analyses of the above decay modes is presented.
Manifestations of Clustering in Fission of Excited Actinides
2003
A new, graphical way of extracting important physical information from the total kinetic-energy—mass (TKE—M) distributions of the nuclear reaction products is presented. The resulting images indicate for the first time the presence of the Ni—Mo and Ge—Mo fission modes in the fission of Np nuclei at intermediate excitation energies.
Pulsating B and Be Stars in the Magellanic Clouds
2010
Stellar pulsations in main-sequence B-type stars are driven by the κ-mechanism due to the Fe-group opacity bump. The current models do not predict the presence of instability strips in the B spectral domain at very low metallicities. As the metallicity of the Magellanic Clouds (MC) has been measured to be around Z = 0. 002 for the Small Magellanic Cloud (SMC) and Z = 0. 007 for the Large Magellanic Cloud (LMC), they constitute a very suitable objects to test these predictions. The aim of this work is to investigate the existence of B-type pulsators at low metallicities, searching for short-term periodic variability in a large sample of B and Be stars from the MC with accurately determined f…
Search for the DecayB+→K+νν¯
2005
We search for the rare flavor-changing neutral-current decay ${B}^{+}\ensuremath{\rightarrow}{K}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ in a data sample of $82\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected with the BABAR detector at the PEP-II $B$-factory. Signal events are selected by examining the properties of the system recoiling against either a reconstructed hadronic or semileptonic charged-$B$ decay. Using these two independent samples we obtain a combined limit of $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{K}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}})l5.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ at the 90% confidence level. In addition, by…
A diffusion Monte Carlo study of small para-Hydrogen clusters
2007
Abstract An improved Monte Carlo diffusion model is used to calculate the ground state energies and chemical potentials of parahydrogen clusters of three to forty molecules, using two different p-H2-p-H2 interactions. The improvement is due to three-body correlations in the importance sampling, to the time step adjustment and to a better estimation of statistical errors. In contrast to path-integral Monte Carlo results, this method predicts no magic clusters other than that with thirteen molecules.
Dynamic Phase Diagram of the REM
2019
International audience; By studying the two-time overlap correlation function, we give a comprehensive analysis of the phase diagram of the Random Hopping Dynamics of the Random Energy Model (REM) on time-scales that are exponential in the volume. These results are derived from the convergence properties of the clock process associated to the dynamics and fine properties of the simple random walk in the $n$-dimensional discrete cube.
Whither the species? Phytophthora taxa, MOTUs and barcodes in the world of metagenomics
2015
The study of ecosystem diversity is being transformed by high throughput sequencing technology that allows an unparalleled depth of sampling of DNA barcode sequences. The opportunities are great at this fascinating interface of pathology, ecology, taxonomy and molecular biology but there are pitfalls. It is important to consider the potential for bias at all steps in the process from sampling through to data analysis. Increasingly Phytophthora diversity is being examined by metabarcoding of the PCR amplified rDNA ITS regions from soil, water or plant sample DNA. We have applied baiting and isolation, cloning and Sanger sequencing and Illumina MiSeq analysis to a time-series of filtered wate…
La ricerca sui centri storici. Giuseppe Samonà e il Piano Programma per Palermo
2014
Il volume tratta di vari aspetti del Piano Programma, ancora attuali a 30 anni di distanza e malgrado la mancanza di attuazione.
Porosità e increspature
2014
A più di trent’anni dall’approvazione del Piano Programma e della immediatamente successiva scomparsa di Giuseppe Samonà (1983), si intende riprendere alcuni temi fondamentali di quel piano e fornirne una lettura legata all’attualità. Infatti, anche se all’approvazione non seguì praticamente nulla, se non i quattro piani di recupero che però furono trasformati in coerenza col Piano Particolareggiato Esecutivo, gli autori del volume ritengono che quei temi siano ancora utili alla discussione, e ritengono che nel dibattito sul nuovo Piano Regolatore di Palermo, che coincide con questa pubblicazione, possano essere inserite questioni derivate dall’esperienza che viene trattata. I saggi sono ap…