Search results for "Nuclear and high energy physics"
showing 10 items of 8241 documents
Measurement of CP asymmetry in Bs0 → Ds ∓K± decays
2014
Journal of high energy physics 2018(3), 59 (2018). doi:10.1007/JHEP03(2018)059
Search for a fermiophobic Higgs at LEP 2
2001
Higgs bosons predicted by the fermiophobic scenario within Two Higgs Doublets Models were searched for in the data collected by the DELPHI detector at centre-of-mass energies between 189 GeV and 202 GeV, corresponding to a total integrated luminosity of 380 pb^{-1}. No signal was found and confidence limits were derived in the framework of possible extensions of the Standard Model Higgs sector.
Search for a light exotic particle inJ/ψradiative decays
2012
Using a data sample containing 1.06x10^8 psi' events collected with the BESIII detector at the BEPCII electron-positron collider, we search for a light exotic particle X in the process psi' -> pi^+ pi^- J/psi, J/psi -> gamma X, X -> mu^+ mu^-. This light particle X could be a Higgs-like boson A^0, a spin-1 U boson, or a pseudoscalar sgoldstino particle. In this analysis, we find no evidence for any mu^+mu^- mass peak between the mass threshold and 3.0 GeV/c^2. We set 90%-confidence-level upper limits on the product-branching fractions for J/psi -> gamma A^0, A^0 -> mu^+ mu^- which range from 4x10^{-7} to 2.1x10^{-5}, depending on the mass of A^0, for M(A^0)<3.0 GeV/c^2. On…
Top-quark pair + 1-jet production at next-to-leading order QCD
2008
Top-quark pair production with an additional jet is an important signal and background process at the LHC. We present the next-to-leading order QCD calculation for this process and show results for integrated as well as differential cross sections.
Symmetry patterns in the (N, Delta) spectrum
2007
We revise the role played by symmetry in the study of the low-lying baryon spectrum and comment on the difficulties when trying to generalize the symmetry pattern to higher energy states. We show that for the $(N,\Delta)$ part such a generalization is plausible allowing the identification of spectral regularities and the prediction of until now non-identified resonances.
Study of J/ψ and ψ(3686)→Σ(1385)0Σ¯(1385)0 and Ξ0Ξ¯0
2017
Abstract We study the decays of J / ψ and ψ ( 3686 ) to the final states Σ ( 1385 ) 0 Σ ¯ ( 1385 ) 0 and Ξ 0 Ξ ¯ 0 based on a single baryon tag method using data samples of ( 1310.6 ± 7.0 ) × 10 6 J / ψ and ( 447.9 ± 2.9 ) × 10 6 ψ ( 3686 ) events collected with the BESIII detector at the BEPCII collider. The decays to Σ ( 1385 ) 0 Σ ¯ ( 1385 ) 0 are observed for the first time. The measured branching fractions of J / ψ and ψ ( 3686 ) to Ξ 0 Ξ ¯ 0 are in good agreement with, and much more precise than, the previously published results. The angular parameters for these decays are also measured for the first time. The measured angular decay parameter for J / ψ → Σ ( 1385 ) 0 Σ ¯ ( 1385 ) 0 , …
Antineutrino induced Λ(1405) production off the proton
2015
We have studied the strangeness-changing antineutrino-induced reactions ${\overline{\ensuremath{\nu}}}_{l}p\ensuremath{\rightarrow}{l}^{+}\ensuremath{\phi}B$, with $\ensuremath{\phi}B={K}^{\ensuremath{-}}p$, ${\overline{K}}^{0}n$, ${\ensuremath{\pi}}^{0}\ensuremath{\Lambda}$, ${\ensuremath{\pi}}^{0}{\ensuremath{\Sigma}}^{0}$, $\ensuremath{\eta}\ensuremath{\Lambda}$, $\ensuremath{\eta}{\ensuremath{\Sigma}}^{0}$, ${\ensuremath{\pi}}^{+}{\ensuremath{\Sigma}}^{\ensuremath{-}}$, ${\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{+}$, ${K}^{+}{\ensuremath{\Xi}}^{\ensuremath{-}}$, and ${K}^{0}{\ensuremath{\Xi}}^{0}$, using a chiral unitary approach. These ten coupled channels are allowed t…
Λb→J/ψKΞdecay and the higher order chiral terms of the meson baryon interaction
2015
We study the weak decay of the ${\mathrm{\ensuremath{\Lambda}}}_{b}$ into $J/\ensuremath{\psi}K\mathrm{\ensuremath{\Xi}}$ and $J/\ensuremath{\psi}\ensuremath{\eta}\mathrm{\ensuremath{\Lambda}}$ states, and relate these processes to the ${\mathrm{\ensuremath{\Lambda}}}_{b}\ensuremath{\rightarrow}J/\ensuremath{\psi}\overline{K}N$ decay mode. The elementary weak transition at the quark level proceeds via the creation of a $J/\ensuremath{\psi}$ meson and an excited $sud$ system with $I=0$, which upon hadronization leads to $\overline{K}N$ or $\ensuremath{\eta}\mathrm{\ensuremath{\Lambda}}$ pairs. These states undergo final-state interaction in coupled channels and produce a final meson-baryon p…
Erratum to: “Low lying S=−1 excited baryons and chiral symmetry”
2002
Are there three Xi (1950) states?
2012
Different experiments on hadron spectroscopy have long suspected the existence of several cascade states in the $1900-2000 {\rm MeV}$ region. They are usually labeled under the common name of $\Xi (1950)$. As we argue here, there are also theoretical reasons supporting the idea of several $\Xi (1950)$ resonances. In particular, we propose the existence of three $\Xi(1950)$ states: one of these states would be part of a spin-parity $(1/2)^{-}$ decuplet and the other two probably would belong to the $(5/2)^{+}$ and $(5/2)^{-}$ octets. We also identify which decay channels are the more appropriate for the detection of each of the previous states.