Search results for "branching"
showing 10 items of 918 documents
Antiproton-proton annihilation at rest intoπ + π − η ′ andπ + π − η from atomicS andP states
1990
We have measured the branching ratios for\(\bar pp\) annihilation at rest intoπ+π−η andπ+π−η′ in hydrogen gas in two data samples that have different fractions ofS-wave andP-wave initial states. The branching ratios are derived from a comparison with the topological branching ratio for\(\bar pp\) annihilations into four charged pions of (49±4)% and the branching ratio intoπ+π−π+π−π0 of (18.7±1.6)%. We find a significant reduction of the branching ratios fromP-states for\(\bar pp \to \pi ^ + \pi ^ - \eta \) andπ+π−η′ in comparison toS-state annihilation. $$\begin{gathered} BR(S - wave \to \pi ^ + \pi ^ - \eta ) = (13.7 \pm 1.46) \cdot 10^{ - 3} \hfill \\ BR(P - wave \to \pi ^ + \pi ^ - \eta …
New Features in the Systematics of Low‐Spin States in Even 106‐120Cd
1991
Low‐spin states in even 106‐112Cd and 116Cd were investigated by in‐beam and off‐beam γ‐ray and conversion‐electron spectroscopy. New spin assignments and decay branching ratios for the levels in 106Cd,108Cd,110Cd and 112Cd were obtained. From the new systematical data for the even 106‐120Cd, it is inferred that two sets of low‐lying 0+ states cross between 114Cd and 116Cd. One of these sets appears to have features of both intruder and two‐quadrupole‐phonon states.
Cluster Structure of9Be from3He+9Be Reaction
2016
The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a 9Be target with a 3He beam at an incident energy of 30 MeV. Angular distributions for 9Be(3He,3He)9Be, 9Be(3He,4He)8Be, 9Be(3He,7Be)5He, 9Be(3He,6Li)6Li and 9Be(3He,7Li)5Li reaction channels were measured. Cross sections for channels leading to unbound 5He g.s ., 5Li g.s . and 8Be systems were obtained from singles measurements where the relationship between the energy and the scattering angle of the observed stable ejectile is constrained by two-body kinematics. Information on the cluster structure of 9Be was obtained from the transfer channels. It was concluded that cluster transfer is an …
Structure ofIn112nucleus
1988
The \ensuremath{\gamma}-ray spectra of the $^{112}\mathrm{Cd}$(p,n\ensuremath{\gamma}${)}^{112}$In and $^{109}\mathrm{Ag}$(\ensuremath{\alpha},n\ensuremath{\gamma}${)}^{112}$In reactions were measured with Ge(Li) spectrometers for bombarding energies of 4.8 MeV protons and 17.1 MeV \ensuremath{\alpha} particles. The energies and relative intensities of 79 $^{112}\mathrm{In}$ \ensuremath{\gamma}-ray transitions have been determined. The electron spectra were measured with combined magnet plus Si(Li) as well as superconducting magnetic lens plus Si(Li) spectrometers. Internal conversion coefficients of 40 $^{112}\mathrm{In}$ transitions have been determined, and the level scheme of $^{112}\ma…
Fine structure in Po α-decay and shape coexistence in Pb
1998
Abstract Excited Jπ=0+ states in 188 Pb populated in the α-decay of 192 Po have been identified through α-particle/conversion electron coincidences. α-particle energies and branching ratios have been measured, and hindrance factors deduced. The level scheme has been fitted using a configuration mixing calculation, providing estimates of the mixing matrix elements, mixing amplitudes and the energies of unperturbed and unobserved levels.
Systematic study of low-spin states in even Cd nuclei.
1992
Low-lying low-spin collective states in even $^{106\mathrm{\ensuremath{-}}112}\mathrm{Cd}$ and $^{116}\mathrm{Cd}$ were investigated using in-beam and off-beam \ensuremath{\gamma}-ray and conversion-electron spectroscopy. New spin assignments and decay branching ratios for the levels in $^{106}\mathrm{Cd}$, $^{108}\mathrm{Cd}$, $^{110}\mathrm{Cd}$, and $^{112}\mathrm{Cd}$ were obtained. The present results essentially complement the level systematics from $^{106}\mathrm{Cd}$ to $^{120}\mathrm{Cd}$. From the new data, it is inferred that two sets of low-lying ${0}^{+}$ states having different excitation characteristics cross between $^{114}\mathrm{Cd}$ and $^{116}\mathrm{Cd}$. No correspondi…
Measurement of an Excess in the Yield ofJ/ψat Very LowpTin Pb–Pb Collisions atsNN=2.76 TeV
2016
We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT< 0.3 GeV/c) in peripheral hadronic Pb-Pb collisions at √sNN = 2.76 TeV, performed by ALICE at the CERN LHC. Remarkably, the measured nuclear modification factor of J/ψ in the rapidity range 2.5< y< 4 reaches about 7 (2) in the pT range 0- 0.3 GeV/c in the 70-90% (50-70%) centrality class. The J/ψ production cross section associated with the observed excess is obtained under the hypothesis that coherent photoproduction of J/ψ is the underlying physics mechanism. If confirmed, the observation of J/ψ coherent photoproduction in Pb-Pb collisions at impact parameters smaller than twice the nuc…
Production cross section and decay study of Es243 and Md249
2019
In the study of the odd-$Z$, even-$N$ nuclei $^{243}$Es and $^{249}$Md, performed at the University of Jyv\"askyl\"a, the fusion-evaporation reactions $^{197}$Au($^{48}$Ca,2$n$)$^{243}$Es and $^{203}$Tl($^{48}$Ca,2$n$)$^{249}$Md have been used for the first time. Fusion-evaporation residues were selected and detected using the RITU gas-filled separator coupled with the focal-plane spectrometer GREAT. For $^{243}$Es, the recoil decay correlation analysis yielded a half-life of $24 \pm 3$s, and a maximum production cross section of $37 \pm 10$ nb. In the same way, a half-life of $26 \pm 1$ s, an $\alpha$ branching ratio of 75 $\pm$ 5%, and a maximum production cross section of 300 $\pm$ 80 nb…
Search for the Rare Leptonic Decay B+→μ+νμ
2004
A search for the rare leptonic decay with data collected at the resonance by the BABAR experiment was carried out. The decay rate was sensitive to the product of the Cabibbo Kobayashi Maskawa matrix element (Vub and the B decay constant fb, which was propotional to the wave function for zero separation between the quarks. The data used in the analysis was collectd with BABAR detector at the PEP-II storage ring and the sample consisted of an integrity luminosity of 81.4 fb-1. The systematic uncertainty in the signal efficiency was evaluated which included the muon candidate selection and the reconstruction efficiency of the companion B.
Search for doubly charged higgs bosons with lepton-rlavor-violating decays involving τ leptons
2008
We search for pair production of doubly charged Higgs particles (H(+/-+/-)) followed by decays into electron-tau (e tau) and muon-tau (mu tau) pairs using data (350 pb(-1)) collected from (p) over barp collisions at root s = 1.96 TeV by the CDF II experiment. We search separately for cases where three or four final-state leptons are detected, and combine results for exclusive decays to left-handed e tau (mu tau) pairs. We set an H(+/-+/-) lower mass limit of 114(112) GeV/c(2) at the 95% confidence level. RI Ruiz, Alberto/E-4473-2011; Robson, Aidan/G-1087-2011; De Cecco, Sandro/B-1016-2012; Prokoshin, Fedor/E-2795-2012; Azzi, Patrizia/H-5404-2012