Search results for "Time based"
showing 5 items of 5 documents
First Measurement of the Absolute Branching Fraction of Λ→pμ−ν¯μ
2021
The absolute branching fraction of Λ→pμ−ν¯μ is reported for the first time based on an e+e− annihilation sample of 10×109 J/ψ events collected with the BESIII detector at s=3.097 GeV. The branching fraction is determined to be B(Λ→pμ−ν¯μ)=[1.48±0.21(stat)±0.08(syst)]×10−4, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe−ν¯e), we obtain the ratio {[Γ(Λ→pμ−ν¯μ)]/[Γ(Λ→pe−ν¯e)]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pμ−ν¯μ and Λ¯→p¯μ+νμ is also determined, and no evidence for CP violation is fo…
The Astrophysical r-process
2002
In 1957, Burbidge, Burbidge, Fowler and Hoyle (B2FH) provided a basis for forty years of research in various aspects of nucleosynthesis in stars. We will focus in this paper on progress in r-process nucleosynthesis, with emphasis on the most recent developments in nuclear physics. In 1986, the first experimental data on two crucial, neutron-magic “waiting-point” nuclei provided valuable clues to the astrophysical conditions and the nature of the r-process site. Beginning in the 1990’s, our group (FK2L) presented considerably improved r-abundance calculations, which were for the first time based on a modern, internally consistent nuclear-theory input. The phenomenon of shell-quenching far fr…
Drumming signals within the family Taeniopterygidae (Plecoptera)
2014
Drumming signals of the 11 species of Palaearctic Taeniopterygidae are described for the first time based on the study of populations from nine different European countries from Spain to Russia. In this way, a contribution is made to our knowledge of the constancy respectively the divergence of signals typical for the species distributed over a very wide area. Communication patterns of the family under varying temperatures were analysed. The dependence on temperature indicates that the adults of this family are cold stenothermic insects. Within the genus Brachyptera (Newport, 1851), the call signal of males is significantly different from their response signal (duration and drumming frequen…
Assessment of the production costs curve in micro-grids: a comparative analysis
2012
In micro-grids, due to their small scale, there is commonly only one power supplier. A competitive wholesale market hardly exists so the question about how to consider market issues for small producers within micro-grids arises. On the other hand, the specific features of micro-grids where load and generated power hardly find a balance, require that customers take part to regulation issues, maybe using demand response programs. In this paper, price responsive policies and its programs are discussed to answer this question. A case study of a micro-grid with one microturbine and two photovoltaic generators in Italy is analyzed to assess the overall production cost in order to build a price re…
A study on the assessment of the production costs curves in micro-grids
2013
In micro-grids, due to their small scale, there is commonly only one power supplier. A competitive wholesale market hardly exists, so the question about how to consider market issues for small producers within micro-grids arises. On the other hand, the specific features of micro-grids where load and generated power hardly find a balance, require that customers take part to regulation issues, also using demand-response (DR) programs. In this paper, price responsive (PR) policies and their programs are discussed to answer this question. A case study of a micro-grid with one micro-turbine and two photovoltaic (PV) generators is analyzed to assess the overall production cost in order to build a…