Donald H. Miller

Influence of the Λ π Resonance on Correlations in the Reaction K − + d → Λ + π − + p

Author(s): Dahl, Orin I.; Horwitz, Nahmin; Miller, Donald H.; Murray, Joseph J.; White, Paul G.

Inclusive production of D-mesons in e+e− annihilation at 7 GeV☆

Abstract Inclusive momentum and energy spectra of neutral and charged D-mesons produced in e+e− annihilation at energies near 7 GeV are presented. The slope of the energy spectrum is similar to the charged pion spectrum at the same energy. The inclusive cross section σ(e+e−→ D or D + anything) at 7 GeV is 4.8±1.3 nb.

A Kπ resonant state at 726 MeV

Author(s): Miller, Donald H.; Alexander, Gideon; Dahl, Orin I.; Jacobs, Laurence; Kalbfleisch, Goerge R.; Smith, Gerald A.

Search for highly-interacting, fractionally-charged particles in electron-positron annihilation at 29 GeV☆

Abstract We have searched for relativistic, highly-interacting fractionally-charged particles using the free-quark detector at the e + e − storage ring PEP. No convincing events were seen. For an assumed interaction cross section with matter of 100 times geometric, 90% confidence level upper limits on their production relative to e + e − → μ + μ − are between 0.025 and 0.49 depending on quark mass (up to 13 GeV/ c 2 ) and reaction type. These are the first published limits on the production of fractionally charged particles with interaction cross sections of 100 times geometric or larger.

A SEARCH FOR NEUTRAL HEAVY LEPTONS

Abstract In e + e − annihilations at SPEAR we have searched for narrow neutral resonances in the eπ and μπ channels for masses between 0.5 GeV/ c 2 and 1.5 GeV/ c 2 . No evidence for such states has been found. Under standard theoretical assumptions for production cross sections and decay branching ratios of heavy leptons a lower limit of 1.2 GeV/ c 2 can be set on the mass.

π+n→ η p: A Regge parametrization over a large energy range using Veneziano-type residue functions

Abstract A low-background sample of approximately 350 events from the reaction π + n→ η p has been obtained from a study of the reaction π + d→p pπ + π − π o in a bubble chamber experiment with indicent pion momentum between 1.1 and 2.4 GeV/ c . The η production angular distributions and the total η cross section are well fitted by a simple two-parameter Reggeized A 2 -exchange model with Veneziano-type residue functions and a normal-slope A 2 trajectory. The parametrization is also compared with data from other experiments spanning the incident momentum range from near threshold to 18.2 GeV/ c . Although agreement is very good for the total cross section, present data indicate that the parametrization exhibits too much shrinkage at the highest energies.

Study of the I = 2 Σπ system in π + N interactions

A study of the effective-mass distributions for systems recoiling against mesons (k/sup +/) produced both in pi /sup -/ + p and pi /sup -/ + n interactions is reported. Although all the known energetically accessible resonances are produced the data show no systematic enhancement that can be identified as arising from an I = 2 Y pi resonant state. A more favorable situation exists for SIGMA /sup -/ pi /sup 0/ and SIGMA /sup 0/ pi /sup -/ systems recoi ling against mesons(k/sup +/). The effective-mass distributions for all two-body final states produced in association with mesons(k/sup +/) are plotted. (C.E.S.) perimentally observed nucleon-nucleon scattering. Requirements of unitarity were not imposed, and the dispersion relations depend only on causality and the empirical spectrum of masses, spins, parities, and coupling constants. (C.E.S.)

CP-Violating charge asymmetry in the decay KL0 → πμν

Abstract The K μ 3 0 charge asymmetry has been measured to be (6.0 ± 1.4) × 10 −3 . The error contains a major systematic contribution. Large corrections were made in order to exclude neutron-induced background events and to correct for the range difference between μ + and μ − .

EVIDENCE FOR THE EXISTENCE OF A K

Author(s): Miller, Donald H.; Alexander, Gideon; Dahl, Orin I.; Jacobs, Laurence; Kalbfleisch, George R.; Smith, Gerald A.

pi

Author(s): Dahl, Orin I.; Horwitz, Nahmin; Miller, Donald H.; Murray, Joseph J.; White, Paul G.