arXiv subjects

V. A. Mukhin

Publications and source records attributed to V. A. Mukhin.

3 recordsLinked to original sources

arXiv2009

Study of the decay K+ => pi+,nu,nubar in the momentum region 140<Ppi<199 MeV/c

Experiment E949 at Brookhaven National Laboratory has observed three new events consistent with the decay K+ => pi+,nu,nubar in the pion momentum region 140 < P_pi < 199 MeV/c in an exposure of 1.71e12 stopped kaons with an estimated total background of 0.93+-0.17(stat.)+0.32-0.24(syst.) events. This brings the total number of observed K+ => pi+,nu,nubar events to seven. Combining this observation with previous results, assuming the pion spectrum predicted by the standard model, results in a branching ratio of (1.73+1.15-1.05)e-10. An interpretation of the results for alternative models of the decay K^ => pi+,nothing is also presented.

hep-ex↗

arXiv2004

Measurement of the radiative decay width Γ[Λ(1520) --> Λγ] with the SPHINX spectrometer

The radiative decay Λ(1520) --> Λγwas measured directly in the study of exclusive diffractive-like reaction p + N --> Λ(1520) K^+ + N, Λ(1520) --> Λγwith the SPHINX spectrometer. The values of the branching and partial width of this radiative decay were obtained: BR[Λ(1520) --> Λγ] = (1.02+/-0.21(stat)+/-0.15(syst))x10^{-2} and Γ[Λ(1520) --> Λγ] = 159+/-33(stat)+/-26(syst) keV.

hep-ex↗

arXiv2004

Search for Theta(1540)^+ in exclusive proton-induced reaction p+C(N) \to Theta^+ \bar{K}^0 + C(N) at the energy of 70 GeV

A search for narrow Theta(1540)^+, a candidate for pentaquark baryon with positive strangeness, has been performed in an exclusive proton-induced reaction p+C(N) \to Theta^+ \bar{K}^0 + C(N) on carbon nuclei or quasifree nucleons at E_{beam}=70 GeV (sqrt{s} = 11.5 GeV) studying nK^+, pK_S and pK_L decay channels of Theta(1540)^+ in four different final states of the Theta^+ \bar{K}^0 system. In order to assess the quality of the identification of the final states with neutron or K_L we reconstructed Lambda(1520)\to nK_S and phi\to K_LK_S decays in the calibration reactions p+C(N)\to Lambda(1520)K^+ + C(N) and p+C(N)\to pϕ+ C(N). We found no evidence for narrow pentaquark peak in any of the studied final states and decay channels. Assuming that the production characteristics of the Theta^+ \bar{K^0} system are not drastically different from those of the Lambda(1520)K^+ and pϕsystems, we established upper limits on the cross section ratios sigma(Theta^+\bar{K}^0)/sigma(Lambda(1520)K^+) < 0.02 and sigma(Theta^+\bar{K}^0)/sigma(pϕ) < 0.15 at 90% CL and a preliminary upper limit for the forward hemisphere cross section sigma(Theta^+\bar{K}^0) < 30 nb/nucleon.

hep-ex↗