Vladimir Chaloupka

Vladimir Chaloupka
University of Washington Seattle | UW · Department of Physics

About

88
Publications
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Publications

Publications (88)
Article
Octave-circular pitch perception, the repetition of pitch scale qualities when surpassing the octave interval, has been observed in behavioral data from humans and monkeys, but the underlying anatomy and physiology is still unknown. Here we analyze octave circularity in a concert pianist with absolute pitch, both under medication with the neurotrop...
Article
Full-text available
Mass spectra of the reaction (p,2p) at the beam energy 500 MeV on nuclei C,Al,Cu and Pb were measured on two-armed nonmagnetic scintillation spectrometer (candlepower - 0.2 sr, mass allowance - 4 MeV), which is lokated on the TRIUMF cyclotron (Canada). Observable anomalies in these spectra can be stipulated by forming of two-nucleon resonance state...
Article
The Physics Department at the University of Washington recently completed the acquisition of new equipment for teaching the Physics of Music course, as well as for performing various independent study projects in musical acoustics at both undergraduate and graduate levels. The lab setup will be described, as well as the experience after the first y...
Article
The authors propose a set of technology developments relevant to the design of an optimized Cerenkov detector for the study of neutrino interactions of astrophysical interest. Emphasis is placed on signal processing innovations that enhance significantly the quality of primary data. These technical advances, combined with field experience from a fo...
Article
We propose a set of technology developments relevant to the design of an optimized Cerenkov detector for the study of neutrino interactions of astrophysical interest. Emphasis is placed on signal processing innovations that enhance significantly the quality of primary data. These technical advances, combined with field experience from a follow-on t...
Research Proposal
Full-text available
Keyword (s): INSPIRE: proposal| magnet: superconductivity| calorimeter: electromagnetic| calorimeter: hadronic| calorimeter: liquid argon| scintillation counter: plastics| semiconductor detector: pixel| drift chamber| electrode: microstrip| transition radiation detector| tracks: resolution| momentum resolution| spatial resolution: vertex| muon:...
Article
This paper reports a study of an absolute pitch possessor who, upon administration of the psychoactive drug Tegratol (carbamazepine), experienced a significant change in her pitch perception. The subject's performance both in producing, as well as in identifying, random-frequency tones was measured, covering the period of administration of the drug...
Article
Employing the decay chain K+→π+π0, π0→e+e- we have observed the decay π0→e+e-. With a signal sample of ≊21 events we measure the branching ratio for π0→e+e- to be (6.9±2.3±0.6)×10-8, normalized to the decay K+→π+π0, π0→e+e-γ. This result is consistent with the unitarity lower bound and the published 90% confidence level upper limit of 13×10-8.
Article
This paper reports on a study of an absolute pitch possessor who, upon administration of the psychoactive drug Tegretol (carbamazepine), experienced a significant change in her pitch perception. The subject’s performance both in producing as well as in identifying random tones was measured, covering the period of administration of the drug, as well...
Article
We present results of an experiment in which approximately 500 events of the decay K+→π+e+e- were observed. We have measured the branching ratio for Kπee+ to be (2.75±0.23±0.13)×10-7 assuming a vector interaction with a form factor of λ=0.105±0.035±0.015. We have also found the branching ratio times decay probability for K+→π+X0, X0→e+e- to be less...
Article
A search for the lepton-flavor number-violating decay K+→π+μ+e- has been conducted at the Brookhaven Alternating Gradient Synchrotron. No candidates have been found which would be consistent with this decay mode. An upper limit on the branching ratio is placed at 2.6×10-10, which can be combined with our previous result to yield an upper limit of 2...
Article
A search for the lepton family number violating decay K+ → π+μ+ e− has been performed. We established an upper limit on its branching ratio of 1.1 × 10−9 at the 90 % C.L. Measurements have also been made for the decay K+ → π+ e+ e−. A description of the measurement technique and some preliminary results are presented.
Conference Paper
The progress of AGS Experiment 777, a search for K/sup +/..--> pi../sup +/..mu../sup +/e/sup -/ is described. Results on the decay K/sup +/..--> pi../sup +/A/sup 0/, where A/sup 0/ is a weakly interacting neutral particle that decays into e/sup +/e/sup -/ and preliminary results on the direct decay K/sup +/..--> pi../sup +/e/sup +/e/sup -/ are pres...
Article
The progress of AGS Experiment 777, a search for K+-->pi+mu+e- is described. Results on the decay K+-->pi+A0, where A0 is a weakly interacting neutral particle that decays into e+e- and preliminary results on the direct decay K+-->pi+e+e- are presented as well as new limits on pi0-->mu+e-.
Article
We report here on a search for the lepton-family-number-violating decay K+→π+μ+e-. We found no evidence for this decay mode and we establish an upper limit on its branching ratio of 1.1×10-9 at the 90% confidence level (C.L.) for a uniform phase-space decay distribution. We also use this result to establish an upper limit for the branching ratio of...
Conference Paper
A search for the lepton-flavor violating decay K/sup +/..--> pi../sup +/..mu../sup +/e/sup -/ has been performed. Measurements have also been made of the branching ratio and decay particle distributions for the decay K/sup +/..--> pi../sup +/e/sup -/. A description of the measurement technique, and preliminary results are presented. 6 refs., 5 figs...
Article
We have searched for the decay process K+-->pi+A0, where A0 is any particle of mass less than 100 MeV/c2 decaying into e+e-. Upper limits for the branching ratio are given as a function of mass and lifetime of the A0. For lifetimes shorter than 10-13 sec, a limit of 4.5×10-7 at the 90% confidence level is obtained.
Conference Paper
The GRANDE experiment is a unique ''next-generation'' detector capable of making significant contributions to the fields of ..nu.. and ..gamma..-ray astrophysics as well as performing important ''conventional'' high-energy physics investigations. The detector, which covers an area of 250 m /times/ 250 m, is based on the well proven water Cerenkov t...
Article
We report evidence for the existence of a charged narrow state of mass M ∼ 2.02 GeV/c2 and widtt Γ ⪅ 0.04 GeV/c2, decaying into . The state is observed in the reaction at 6 GeV/c and in at 9 GeV/c in a triggered bubble chamber experiment at the SLAC Hybrid Facility.
Article
We have made a measurement of very-low-energy ${e}^{+}{e}^{$-${}}$ pair production from ${$\pi${}}^{\ifmmode\pm\else\textpm\fi{}}p$ collisions at 18 GeV/c. Using the SLAC 1-m bubble chamber to study a sample of 178\ifmmode\times\else\texttimes\fi{}${10}^{3}$ interactions, we find a signal of centrally produced direct ${e}^{+}{e}^{$-${}}$ pairs whic...
Article
Results are presented on vector meson production in the hypercharge exchange reactions: pi+p-->K*+(890)Y+ and K-p-->rho-Y+ where Y+ is either Sigma+ or Y*+(1385). These reactions have been studied at 7 GeV/c and 11.5 GeV/c using the SLAC Hybrid Facility. Total and differential cross sections, hyperon polarization, and vector meson decay angular dis...
Article
We have measured in a single experimental setup, the differential cross sections and decay angular distributions of the Y∗ (1385) produced in the two line-reversed reactions: (190 events/ωb) at 11.5 GeV/c. The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find the differential cross sections an...
Article
With use of the Stanford Linear Accelerator Center hybrid facility 1-m bubble chamber fitted with tantalum plates, a measurement was made of direct unexplained e+e- pair production in 18-GeV/c pi+/-p interactions. Limits are set in pi+p processes. In pi-p a signal is observed which cannot be caused by eta, omega, or rho decay, and for masses >mpi0,...
Article
We have measured in a single experimental setup the differential cross sections and polarizations of the Y*(1385) produced in the two line-reversed reactions pi+p-->K+Y*(1385) (260 eV/mub) and K-p-->pi-Y*(1385) (180 eV/mub) at 11.5 GeV/c. We compare these results to Sigma+ production in the same experiment. The data have been derived from a trigger...
Article
A multidimensional analysis of the reaction π−p → π−pπ+π− at 3.93 GeV/c is presented. Its results are compared to those obtained with conventional methods and its limitations are discussed.
Article
Two experiments to study the low-mass diffractive enhancement recoiling against a fast forward pion from π+p and π-p collisions at 14 GeV/c are described. Photographs of the SLAC 40-in. hydrogen bubble chamber were triggered by a downstream spectrometer when the missing mass, calculated on-line, was above 1.1 GeV. Evidence for a nonresonant mass pe...
Article
An analysis of about 60 000 events produced in the reaction π−A → (π+π−π−)A on nine different nuclear targets A at 8.9, 12.9, and 15.1 GeV/c has been performed using the Illinois PWA program.In the A1 region our “coherent” sample of events (which contains about 11% of incoherently produced events) is described by only four partial waves: the 1+S an...
Article
We have measured for the first time in one detectorathe complete decay angular distribution on Y* + An, A + pr- in the two line-reversed reactions: n+p + K+Y*(1385) and K-p -t a-Y*(1385). Our experiment was conducted in the SLAC 1 m rapid cycling bubble chamber (15 Hertz) trig- gered by electronic detectors and an online algorithm. The Extended Max...
Article
The spin parity of the η′ (958) is studied in the reaction K−p → η'Λ at 4.2 GeV/c, using bubble chamber data with a statistical sensitivity of 128 events/μb. The data unambiguously prefer the 0− assignment.
Article
A partial-wave analysis of the (3π)0 system produced peripherally in the reaction K-p --> π+π-π0 Λ at 4.2 GeV/c is presented. The observation of the weak Λ decay allows a determination of all the transversity production amplitudes except for two phases. The production of known resonances having decay modes other than 3π is used to test the isobar m...
Article
This supplement to the 1976 edition of “Review of particle properties”, Particle Data Group [Rev. Mod. Phys. 48, No. 2, Part II (1976)], contains tabulations of experimental data bearing on the “new particles” and related topics; categories covered include charmed particles, ψ's and their decay products, and heavy leptons. Errata to the previous ed...
Article
A partial-wave analysis of the (3pi)0 system produced peripherally in the reaction K-p --> pi+pi-pi0 Lambda at 4.2 GeV/c is presented. The observation of the weak Lambda decay allows a determination of all the transversity production amplitudes except for two phases. The production of known resonances having decay modes other than 3pi is used to te...
Article
Using an 880 events per microbarn sample of K-p interactions at 4.2 GeV/c the production and decay properties of the delta (970) have been investigated in the following reactions: K-p --> Sigma+(1385)etapi- and K-p ar Sigma+(1385)K0K-.
Article
A partial wave analysis of the K0pi+pi- system produced in the charge exchange reaction K-p --> (K 0pi+pi-)n at 4.2 GeV/c has been performed both as a function of Kpipi mass and of t'. The 1+S wave forms the largest contribution to the Kpipi system and peaks at roughly the same mass as the Q in diffractive Kpipi production. The polarization propert...
Article
The presence of a structure in the p̄p total cross section at 1930–1940 MeV, with a narrow width of 9 MeV is confirmed. The interpretation of the effect as a single, non interfering, resonance is made difficult by the comparison of the elastic scattering with the charge exchange cross sections.
Article
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group (Phys. Letters 50B, No.1 (1974), and Supplement, Rev. Mod. Phys. 47 (1975) 535). Data are evaluated, listed, averaged, and summarized in tables. Numerous tables, figures, and formulae of interest to particle physicists...
Article
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Phys. Letters 50B, No. 1 (1974), and Supplement, Rev. Mod. Phys. 47 (1975) 535]. Data are evaluated, listed, averaged, and summarized in tables. Numerous tables, figures, and formulae of interest to particle physicists...
Article
Recently available differential cross section and density matrix information on pi /sup -/p to B/sup -/p at 4 GeV/c are successfully described in terms of t channel exchanges and s channel absorptive effects. The s channel helicity amplitude which is dominant at small mod t mod (zero net helicity flip omega exchange) is found to have a zero at -t=0...
Article
This supplement to the 1974 edition of "Review of Particle Properties," Particle Data Group [Phys. Lett. 50B, No. 1 (1974)], contains an announcement concerning the postponement of the usual Review, a list of Errata, and a tabulation of the experimental results on the newly discovered mesons.
Article
The reaction π−p → A−2p at 3.9 GeV/c incident momentum is studied using data corresponding to the ϱ°π−, ηπ− and KδsK− decay modes of the A−2. Unnatural parity exchange is found to be important at this energy. The natural parity exchange component of the differential cross section exhibits structure at t′ ≈ GeV2.
Article
Results of a mass-independent spin-parity analysis of the mupi system from the reaction pi-p-->pmupi- at 3.9, 5 and 7.5 GeV/c are presented. We obtain a unique JP = 1+ assignment for the B meson as well as results on its production density matrix and the D/S ratio of its decay.
Article
We have investigated the final states K ∗0(890)Σ, K∗0(890)Σ 0 and K ∗0(890) Y 1∗0(1385) produced in π-p interactions at 3.93 GeV/ c. We present the differential cross sections and spin density matrix elements for the resonances as functions of momentum transfer, as well as the gL and Σ0 polarizations. The Σ0 polarization is found to be positive and...
Article
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Rev. Mod. Phys. 45, No. 2, Part II, Supplement (1973)]. Data are evaluated, listed, averaged, and summarized in tables.
Article
A detailed analysis is presented of about 6000 events belonging to the final states p2π+3π−, p2π+3π−π0 and n3π+3π− produced in π−p interactions at 3.93 GeV/c. The main features of the data are found to be well approximated by the predictions of relativistic phase-space, in spite of copious resonance production amounting to approximately 80% of the...
Article
We present new evidence for the decay fO --> pi+pi+pi-pi- from pi- p interactions at 3.93 GeV/c. The branching ratio fO --> pi+pi+pi-pi-/fO --> pi+pi- is determined to be (6.5-1.7+1.0)%. Now at the Institute of Experimental Physics, Warsaw University, Warsaw.
Article
A modified Chew-Low extrapolation procedure is applied to the reaction π−p→Δ++π−π− to extract the I = 2 ππ elastic cross sections from threshold to 1260 MeV. The predictions of the one-pion-exchange model are used to estimate the contributions from background processes of the type π−p→Δ0ϱ0. The moments of the π−π− angular distribution are also extr...
Article
We have investigated the final states K*0(890)Sigma, K*0(890)Sigma0 and K*0(890) Y1*0(1385) produced in pi-p interactions at 3.93 GeV/c. We present the differential cross sections and spin density matrix elements for the resonances as functions of momentum transfer, as well as the gL and Sigma0 polarizations. The Sigma0 polarization is found to be...
Article
We have measured the branching fractions of the A2− meson, produced in the reaction π−p → pA2− at 3.9 GeV/c incident momentum. The rates for the ηπ and K modes relative to ϱπ are 0.211 ± 0.044 and 0.056 ± 0.014, respectively. The upper limit for the η′π mode is 0.056 at the 90% confidence level. We have also looked for an ωππ decay of the A2− and o...
Article
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group (Phys. Letters 39B, No. 1 (1972) ). Data are evaluated, listed, averaged, and summarized in tables. A data booklet is also available.
Article
A study of π -p → K∗Λ and π -p → K∗Σ° at 3.9 GeV/c indicates that the main features of both reactions can be interpreted in terms of simple exchange processes, the first involving both natural and unnatural exchange, the second showing evidence for natural parity exchange only.
Article
Differential cross sections and polarizations have been measured for the reaction π-p → K 0Λ and π-p → K 0Σ0 at 3.9 GeV/ c π - momentum. Comparison of these data with those of the related reactions K -n → π-Λ and K -p → π-Σ+ (at approximately the same c.m. energy) indicate that simple Regge-pole models involving only K ∗(890) and K ∗(1420) exchange...
Article
A spin-parity ( JP) analysis of the 3π system is presented for a sample of events of the type π-p → p π-π+π-. Using the maximum-likelihood fitting procedure, the behaviour of different JP states for the intermediate ρπ system has been investigated as a function of the 3 π effective mass. The analysis gives a clear indication for a JP = 2 +ρπ resona...
Article
In this paper we present evidence for a constructive interference effect between the 2π decays of the ω and the ϱo observed in the reaction π−p → pπ+π−π− at 3.9 GeV/c. From analysis of the π+π− mass spectrum, we obtain for the branching ratio Γ(ω → π+π−)/Γ(ω → π+π−π0) a lower limit of 1.1% at the 95% confidence level.
Article
12357 events from antiproton-proton annihilations into kaons and pions have been analysed. Partial cross sections are determined for various KK + npi(n = 0,1,2...) final states and the total cross section is found to be (3.5 +/- 0.3) mb. The angular and the momentum distributions are presented and compared with the predictions of theoretical models...
Article
A spin-parity (JP) analysis of the 3pi system is presented for a sample of events of the type pi-p --> ppi-pi+pi-. Using the maximum-likelihood fitting procedure, the behaviour of different JP states for the intermediate rhopi system has been investigated as a function of the 3pi effective mass. The analysis gives a clear indication for a JP = 2+ r...
Article
E777 at the Brookhaven AGS has published a final branching ratio limit for the lepton family violating decay K{sup +} â Ï{sup +}μ{sup +}e⁻ of 2.1 à 10⁻¹° (90% C.L.). New results based on approximately 500 events of the G.I. M. suppressed decay K{sup +} â Ï{sup +}e{sup +}e⁻ have yielded a branching ratio of (2.75 {plus minus} 0.23 {plus min...
Article
Results of our search for short lived neutral particles emitted in K/sup +/ decay are given. We also seek to make an accurate measurement of the branching ratio for ..pi..° ..-->.. e/sup +/e⁻ by looking for the decay chain K/sup +/ ..-->.. ..pi../sup +/..pi..°, ..pi..° ..-->.. e/sup +/e⁻. The world average branching ratio for this decay is (...
Article
In these lectures, we discuss the link between human interactions in large communities on the one hand, and the modern, state-of-the-art computing and communication tools on the other hand. The scope of the lectures is broader than the original title indicates. After a review of the relevant aspects of the psychology of programming, some remarks on...