Related papers: True parameters of He-4-Sigma hypernucleus
Sigma+ hyperon production was measured at the COSY-11 spectrometer via the p p --> n K+ Sigma+ reaction at excess energies of Q = 13 MeV and Q = 60 MeV. These measurements continue systematic hyperon production studies via the p p --> p K+…
We report a measurement of the $\pi^-$ photoproduction beam asymmetry for the reaction $\vec{\gamma} p \rightarrow \pi^- \Delta^{++}$ using data from the GlueX experiment in the photon beam energy range 8.2--8.8 GeV. The asymmetry $\Sigma$…
The reaction gamma + p -> K+ + Sigma + pi was used to determine the invariant mass distributions or "line shapes" of the Sigma+ pi-, Sigma- pi+ and Sigma0 pi0 final states, from threshold at 1328 MeV/c^2 through the mass range of the…
Using an improved "analytic K-matrix model", we reconsider the extraction of the sigma/f_0(600) and f_0(980) gamma-gamma widths from gamma-gamma to pi-pi scatterings data of Crystal Ball and Belle. Our main results are summarized in Tables…
Nonmesonic weak decays of the A=4, and 5 hypernuclei are studied. The short range parts of the hyperon-nucleon weak interactions are described by the direct quark (DQ) weak transition potential, while the longer range interactions are given…
$(\pi^-,K^+)$ hyperon production inclusive spectra with $p_\pi =1.2$ GeV/c measured at KEK on $^{12}$C and $^{28}$Si are analyzed by the semiclassical distorted wave model. Single-particle wave functions of the target nucleus are treated…
In this Letter, the first evidence of the $^4_{\bar{\Lambda}}\overline{\rm He}$ antihypernucleus is presented, along with the first measurement at the LHC of the production of (anti)hypernuclei with mass number $A=4$, specifically…
We have observed a "$K^-pp$"-like structure in the $d(\pi^+,K^+)$ reaction at 1.69 GeV/$c$. In this reaction $\Lambda(1405)$ hyperon resonance is expected to be produced as a doorway to form the $K^-pp$ through the $\Lambda^*p\rightarrow…
A nonperturbative field theoretic calculation has been made for the $s$-shell hypernuclei. Here we dress the $\Lambda$- and $\Sigma$- hypernuclei with off-mass shell pion pairs. The analysis replaces the scalar isoscalar potential by…
We report first results on a deep sub-threshold production of the doubly strange hyperon $\Xi^-$ in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar+KCl was studied with the High Acceptance Di-Electron Spectrometer…
Hypernuclei are bound states of hyperons (Y) and nucleons (N). Measurements on their yields can help us investigate their production mechanisms. In particular, the ${}^5_{\Lambda}$He and $^{4}_{\Lambda}$H(e) are substantially tighter bound…
New results on the production of Xi and Omega hyperons in Pb+Pb interactions at 40AGeV and Lambda at 30AGeV are presented. Transverse mass spectra as well as rapidity spectra of these hyperons are shown and compared to previously measured…
The transparency of the hadrons produced in the $\gamma (n,p) \pi^-$ reaction in nuclei is calculated using the Glauber model modified by including the Fermi motion of the nucleon in the nucleus. Since the calculated results underestimates…
The cross section for production of Phi mesons in proton-nucleus reactions is calculated as a function of the target mass. The decay width of the Phi meson is affected by the change of the masses of the Phi, K+ and K- mesons in the medium.…
We theoretically investigate Lambda production via a (K-, pi-) reaction on a 6Li target, using the distorted-wave impulse approximation (DWIA) with a Fermi-averaged K-n --> pi-Lambda amplitude. We calculate Lambda production spectra using…
The creation of a hypernucleus requires the injection of strangeness into the nucleus. This is possible in different ways, mainly using pi+ or K- beams on fixed targets. A review of hypernuclei production by K- at rest is here presented.…
In a recent experiment E906 at the BNL-AGS, a search for light S=-2 hypernuclei, strong evidence was found for the nuclide Hydrogen-4 double Lambda. One of the most striking components of this data was the appearance of a narrow…
Recent ideas suggest that the 18.6 keV antineutrino (nuebar) line from 2-body decay of 3H in crystals is emitted with natural width, motionally narrowed by lattice vibrations as in recoilless emission. It can be resonantly captured in 3He…
We consider inhomogeneous big bang nucleosynthesis in light of the present observational situation. Different observations of He-4 and D disagree with each other, and depending on which set of observations one uses, the estimated primordial…
The invariant mass spectra of $\phi \to K^{+}K^{-}$ are measured in 12 GeV $p+A$ reactions in order to search for the in-medium modification of $\phi$ mesons. The observed $K^{+}K^{-}$ spectra are well reproduced by the relativistic…