7 research outputs found
Bibliografia sobre evaluacion de colecciones
No full textBibliographical information about the Library Evaluation Techniques. A brief bibliography about how to evaluate a library collection
DIMUON PRODUCTION BY NEUTRINOS IN THE FERMILAB 15-FT. BUBBLE CHAMBER AT THE TEVATRON
No full textThe Fermilab 15-ft bubble chamber has been exposed to a quadrupole triplet neutrino beam produced at the Tevatron. The ratio of to in the beam is approximately 2.5. The mean event energy for -induced charged-current events is 150 GeV, and for -induced charged-current events it is 110 GeV. A total of 64 dimuon candidates (1+, 52 -+ and -, and 11 --) is observed in the data sample of approximately 13 300 charged-current events. The number and properties of the -- and + candidates are consistent with their being produced by background processes, the important sources being and K decay and punchthrough. The 90%-C.L. upper limit for --/- for muon momenta above 4 GeV/c is 1.2×10-3, and for momenta above 9 GeV/c this limit is 1.1×10-3. The opposite-sign-dimuono single-muon ratio is (0.62±0.13)% for muon momenta above 4 GeV/c. There are eight neutral strange particles in the opposite-sign sample, leading to a rate per dimuon event of 0.65±0.29. The opposite-sign-dimuon sample is consistent with the hypothesis of charm production and decay. © 1990 The American Physical Society.079 auteursSCOPUS: ar.jinfo:eu-repo/semantics/publishe
COHERENT PRODUCTION OF pi+ pi- MESONS BY CHARGED CURRENT INTERACTIONS OF NEUTRINOS AND ANTI-NEUTRINOS ON NEON NUCLEI AT THE TEVATRON
No full textCoherent single-pion production on neon nuclei is studied using the Fermilab 15-ft bubble chamber filled with a heavy Ne-H2 mixture and exposed to the Tevatron neutrino beam. In the neutrino energy range 40ε300 GeV, the net signal is 20±6 events, giving a corrected rate per charged-current event of (0.26±0.10)%. The cross section and kinematic distributions agree with the predictions of a model based on partial conservation of axial-vector current and meson dominance. © 1989 The American Physical Society.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Neutral Strange Particle Production in Neutrino and Antineutrino Charged-Current Interactions on Neon
No full textA study has been made of neutral strange particle production in νμNe and ν̄μNe charged-current interactions at a higher energy than any previous study. The experiment was done at the Fermilab Tevatron using the 15-ft. bubble chamber, and the data sample consists of 814(154) observed neutral strange particles from 6263(1115) ν(ν̄) charged-current events. For the ν beam (average event energy Eν=150 GeV), the average multiplicities per charged-current event have been measured to be 0.408±0.048 for K0, 0.127±0.014 for Λ, and 0.015±0.005 for Λ̄, which are significantly greater than for lower-energy experiments. The dependence of rates on kinematical variables has been measured, and shows that both K0 and Λ production increase strongly with Eν, W2, Q2, and yB. Compared to lower-energy experiments, single-particle distributions indicate that there is much more K0 production for xF>-0.2, and the enhanced Λ production spans most of the kinematic region. Λ̄ production is mostly in the region xF-0.2 there is a significant excess of Λ production over the model's prediction. The Λ hyperons are found to be polarized in the production plane. © 1994 The American Physical Society.086 auteursSCOPUS: ar.jinfo:eu-repo/semantics/publishe
Coherent Production of Single Pions and rho Mesons in Charged Current Interactions of Neutrinos and Antineutrinos on Neon Nuclei at the Fermilab Tevatron
No full textThe coherent production of and mesons in ()-neon charged-current interactions has been studied using the Fermilab 15-foot bubble chamber filled with a heavy Ne-H2 mix and exposed to the Tevatron quadrupole triplet (anti)neutrino beam. The () beam had an average energy of 80 GeV (70 GeV). From a sample corresponding to approximately 28 000 charged-current interactions, net signals of (539) coherent events and (197) 0 coherent events are extracted. For E>10 GeV, the coherent pion production cross section is determined to be (3.20.7)×10-38 cm2 per neon nucleus whereas the coherent production cross section is (2.10.8)×10-38 cm2 per neon nucleus. These cross sections and the kinematical characteristics of the coherent events at0(64 auteurs)SCOPUS: ar.jinfo:eu-repo/semantics/publishe
A Measurement of the holographic minimum observable beam branching ratio in the Fermilab 15-foot bubble chamber
No full textHolography has been used successfully in combination with conventional optics for the first time in a large cryogenic bubble chamber, the 15-Foot Bubble Chamber at Fermilab, during a physics run. The innovative system combined the reference beam with the object beam, illuminating a conical volume of ~m. Bubble tracks from neutrino interactions with a width of m have been recorded with good contrast. The ratio of intensities of the object light to the reference light striking the film is called the Beam Branching Ratio. We obtained in our experiment an exceedingly small minimum-observable ratio of . The technology has the potential for a wide range of applications
