Neutral strange particle exclusive production in charged current high-energy antineutrino interactions

The cross section of the quasi-elastic reactions \(\bar v_\mu p \to \mu ^ + \Lambda (\Sigma ^0 )\) in the energy range 5–100 GeV is determined from Fermilab 15′ bubble chamber antineutrino data. TheQ ² analysis of quasi-elastic Λ events yieldsM _A=1.0±0.3 GeV/c² for the axial mass value. With zero µΛ K ⁰ events observed, the 90% confidence level upper limit \(\sigma (\bar v_\mu p \to \mu ^ + \Lambda {\rm K}^0 )< 2.0 \cdot 10^{ - 40} cm^2 \) is obtained. At the same time, we found that the cross section of reaction \(\bar v_\mu p \to \mu ^ + \Lambda {\rm K}^0 + m\pi ^0 \) is equal to \(\left( {3.9\begin{array}{*{20}c} { + 1.6} \\ { - 1.3} \\ \end{array} } \right) \cdot 10^{ - 40} cm^2 \) .     

Diffractive production of charmed strange mesons by neutrinos and antineutrinos

The diffractive production of charmed strangeD _s ^* and possiblyD _s mesons by neutrinos and antineutrinos on nucleons in hydrogen, deuterium and neon targets is observed. The slope parameter of thet distribution is 3.3±0.8 (GeV)^?2. The production rate per charged current neutrino interaction with an isoscalar target times the D _s ⁺ →φτ⁺ branching fraction is (1.03±0.27)×10^?4.     

Observation ofD S ** (2536) meson production by neutrinos in BEBC

Zeitschrift für Physik C Particles and Fields - Neutrino interactions in BEBC produce theD ** (2536) charmed strange meson. The mass of this state is 2534.2±1.2 MeV. The production rate...     

Study ofD *+ and search forD **0 production by neutrinos in BEBC

Data from BEBC experiments are combined to provide large statistics for neutrino interactions. ChargedD ^* mesons are produced in (1.22±0.25)% of neutrino and (1.01±0.31)% of antineutrino charged current interactions. The mean fraction of the hadronic laboratory energy taken by theD ^*+ in these events is 0.59±0.03±0.08. Less than 18% of all chargedD ^* mesons from (anti)neutrino interactions are found to be daughters ofD ^**0 (at the 90% confidence level).     

Study of factorial moments in neutrino changed current interactions on neon and deuterium

Results are presented on the reduced scaled factorial moments of order 2,3,and 4 in ν_μ Ne and ν_μD₂ charged current interaction. Comparisons of the data with a Monte Carlo simulation are presented. The simulation is based on the Lund programs LEPTO 4.3 and JETSET 6.3 and including nuclear reinteractions and smearing due to measurement errors. Nuclear effects are shown to bias the estimate of the intermittency strenghts.     

Spin alignment and parity violation effects inρ 0 production in neutrino and antineutrino charged-current interactions

Most of the measured events on hydrogen, deuterium and neon targets from BEBC at CERN and the 15-foot Bubble Chamber at Fermilab are combined to measure spin-density matrix elements for ⁰ production in the current-fragmentation region in neutrino and antineutrino charged-current interactions. The spin-alignment parameter is found to be 0.08±0.11 for neutrino and 0.41±0.11 for antineutrino interactions. The parity-odd density matrix element Im(₁₀+_–10) is consistent with zero in both reactions. In the combined neutrino and antineutrino data an indication of parity violation is observed: Im _1–1=0.38±0.16 atx _B >0.2,Q ²>8 GeV² andz>0.6.     

Studying(\bar cs) spectroscopy in\bar vN collisions

Charmed strange meson neutrinoproduction is investigated. TheD _s ^? (1970) antineutrino production rate is measured. Two higher \((\bar cs)\) states are seen in the decay channels γD _s ^* (2110) andD ^*K, respectively.     

Bose-Einstein correlations in neutrino and antineutrino interactions with nucleons

Four data sets of charged current neutrino and antineutrino interactions with neon, deuterium and hydrogen collected from BEBC and the 15 Foot Bubble Chamber are used to study the Bose-Einstein correlations between like-sign charged pions. Two forms of the parametrization for the effect are used. No substantial differences are found between the data sets obtained with neon, deuterium and hydrogen targets. The Lorentz invariant parametrization of Goldhaber gives for the radius of the pion emission region the valuer _G =0.80 ±0.04±0.16 fm and for the chaoticity parameter the value =0.61±0.04±0.15. Using the Kopylov-Podgoretskii parametrization yieldsr _K =1.27±0.06±0.12 fm, =0.58±0.03±0.12 and for the pion source lifetimec =0.52±0.05±0.12 fm. The Goldhaber parametrization was used to study the effect in further detail. The same emission radius and the same strength of the effect were found for particles produced in interactions on neutrons and protons. The data are compatible with a spherical shape of the pion emission region. No multiplicity or forward-backward dependences are found. No dependence of the effect on the event kinematical variables is seen.