Vladimir Ammosov

Neutrino production of charmed particles in a hybrid experiment E-564

AbstractCryogenically sensitive nuclear emulsion was placed inside the 15-foot bubble chamber of FNAL and exposed to a wide-band energy (up to 200 GeV) neutrino beam. 194 charged-current neutrino interactions and 13 decays of charmed particles were registered. Using the nuclear emulsion as a vertex detector with the good spectrometric properties of the 15-foot bubble chamber has allowed the decays of charmed particles to be effectively analysed. Attentions is focussed on the new physical results. Λc+ baryon andDs+ meson decay channels, production of charmed ∑c baryons and Λc+ via ∑c. For the first time an event interpreted as production of the excited (cn

Backward emitted protons in interactions of neutrinos with nuclei in photoemulsion

overline s

The INCA Collaboration: present Status and Perspectives

n)-state with mass ∼2790 MeV/c2 has been registered.

Investigation of the properties of punchthrough showers induced by 70-GeV protons in a steel absorber

Abstract An event representing the production and decay of the charmed F+ meson has been identified by means of a 3-constraint fit to decay hypothesis F+ → π+π+π−π0, in which both γ-rays from the π0 converted. The event was produced by a charged current νμ interaction in an emulsion stack located inside the Fermilab 15-foot bubble chamber. The F+ traveled 50 μm, corresponding to a proper time of 1.4 × 10−13 seconds, before decaying in flight. Its mass was determined to be 2017 ± 25MeV.

The INCA project for satellite studies of primary cosmic rays in the energy range 1015 - 1016eV.

Backward emitted protons with momentump>0.3 GeV/c in interactions of neutrino in the energy range 10–200 GeV with photoemulsion nuclei were investigated. Energy spectrum slope parameter of backward protons was measured to beT0=48.9±7.9 MeV. TheA-dependence power index of relative mean yield of backward protons was found to bea=0.68±0.12. A drop in the mean yield of backward protons at the four momentum squared over ∼15 (GeV/c)2 (the neutrino energy over ∼50 GeV) was observed.

TECHNIQUE FOR SEARCHING FOR AND RECONSTRUCTION OF NEUTRINO INTERACTIONS INTHE EMULSION TARGET OF THE SCAP SPECTROMETER

The limits on the parameters of thevμ→vτ oscillations are obtained in the E-564 hybrid experiment: Δm2≦4.5 eV2 and sin2(2θ)≦6.0·10−2 (90% CL). A possibility of direct observation of τ-lepton decays in the nuclear emulsion vertex detector allowed the sensitivity of this experiment to the parameters of the oscillations to be increased.