Search results for "Absolute"
showing 10 items of 518 documents
Feasibility of Coulomb blockade thermometry in metrology
2000
Abstract Coulomb blockade thermometer (CBT) is a simple, magnetic-field-independent primary thermometer for everyday use at cryogenic temperatures. Its properties are well understood by now. The absolute accuracy at present is about ±0.5%. Recently, we have started studying the possibility of using CBT in metrological applications. We have especially in mind the future extension of the international temperature scale below 0.65 K, which is the lower end of ITS-90. Experiments with arrays containing more than 100 tunnel junctions in series are in progress in order to decrease the effects of electromagnetic environment and of co-tunnelling even below the present level.
Regularities of Line Strengths in Spectra of NI, FI, and NeII
1998
Recently experimentally determined individual (fine structure) line strengths for the spectra of NI, FI, and NeII are analysed, searching for regu- larities resulting from similarities in the structure of these species. Strengths of spectral lines of the prominent 3S-3p and 3p-3d transition arrays are investigated. The absolute scales of these experimentally derived data are based on independently determined lifetimes for excited levels of NI, FI, and NeII. The simple Coulomb approximation method was applied for calcula- tions of the matrix elements for the "jumping" electron in order to obtain an average trend in line strengths of the studied emitters. In the case of the isoelectronic spec…
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…
Towards a quantitative comparison between global and local stability analysis
2017
A methodology is proposed here to estimate the stability characteristics of bluff-body wakes using local analysis under the assumption of weakly non-parallel flows. In this connection, a generalisation of the classic spatio-temporal stability analysis for fully three-dimensional flows is first described. Secondly, an additional higher-order correction term with respect to the common saddle-point global frequency estimation is included in the analysis. The proposed method is first validated for the case of the flow past a circular cylinder and then applied to two fully three-dimensional flows: the boundary layer flow over a wall-mounted hemispherical body and the wake flow past a fixed spher…
Measurements of the Absolute Branching Fractions of B±→K±Xcc̅
2006
We study the two-body decays of ${B}^{\ifmmode\pm\else\textpm\fi{}}$ mesons to ${K}^{\ifmmode\pm\else\textpm\fi{}}$ and a charmonium state ${X}_{c\overline{c}}$ in a sample of $210.5\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data from the BABAR experiment. We perform measurements of absolute branching fractions $\mathcal{B}({B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{X}_{c\overline{c}})$ using a missing mass technique, and report several new or improved results. In particular, the upper limit $\mathcal{B}\mathbf{(}{B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}X(3872)\mathbf{)}l3.2\ifmmode…
Das Vorzeichen der Hyperfeinstruktur-Aufspaltung des 3d 5 4s 2 6 S 5/2-Grundzustandes des Mn55
1962
Using a double Fabry-Perot interferometer and an atomic-beam light source, the sign of the hyperfine-structure splitting of the 3d 5 4s 2 6 S 5/2 ground state of Mn55 has been determined to be negative. The absolute value of the splitting previously has been measured byWoodgate andMartin.
High precision measurement of the11Li and9Li quadrupole moment ratio using zero-fieldβ-NQR
2013
The ratio of electric quadrupole moments of 11 Li and 9 Li was measured using the zero-field β-detected nuclear quadrupole resonance technique at TRIUMFISAC. The precision on the ratio Q11/Q9 = 1.0775(12) was improved by more than one order of magnitude and an absolute value for the quadrupole moment of 11 Li was inferred. Systematic effects, as argued here, are not expected to contribute to the ratio on this scale. The zero-field spin-lattice relaxation time for 8 Li implanted within SrTiO3 at 295K in zero-field was found to be T1 = 1.73(2)s. A comparison of the quadrupole moments of 9,11 Li and their ratio is made with the latest models, however, no conclusion may yet be drawn owing to th…
Concluding talk at NOW 2006
2006
This writeup summarizes the status of neutrino oscillations, including recent fluxes and experimental data, as of summer 2006. A discussion is given on the current status of absolute scale of neutrino mass from tritium, neutrinoless double beta decay and cosmological observations, as well as the prospects for the next generation of experiments, including lepton flavor violation searches, and their theoretical significance.
Measurement of resonant andCPcomponents inB¯s0→J/ψπ+π−decays
2014
Structure of the decay Bs0→J/ψπ+π- is studied using data corresponding to 3fb-1 of integrated luminosity from pp collisions produced by the LHC and collected by the LHCb detector. Five interfering π+π- states are required to describe the decay: f0(980),f0(1500),f0(1790),f2(1270), and f2′(1525). An alternative model including these states and a nonresonant J/ψπ+π- component also provides a good description of the data. Based on the different transversity components measured for the spin-2 intermediate states, the final state is found to be compatible with being entirely CP odd. The CP-even part is found to be <2.3% at a 95% confidence level. The f0(500) state is not observed, allowing a limi…
Modelling tribimaximal neutrino mixing
2009
We model tribimaximal lepton mixing from first principles in a way that avoids the problem of the vacuum alignment characteristic of such models. This is achieved by using a softly broken A(4) symmetry realized with an isotriplet fermion, also triplet under A(4). No scalar A(4) triplet is introduced. This represents one possible realization of general schemes characterized by the minimal set of either three or five physical parameters. In the three parameter versions the neutrinoless double beta mass parameter m(ee) vanishes, while in the five parameter schemes the absolute scale of neutrino mass, although not predicted, is related to the two Majorana phases. The model realization we discus…