Search results for "Coin"
showing 10 items of 612 documents
Measurement of the Beam-Helicity Asymmetry in thep(e→,e′p)π0Reaction at the Energy of theΔ(1232)Resonance
2002
In a p((e) over right arrow, e' p)pi(0) out-of-plane coincidence experiment at the three-spectrometer setup of the Mainz Microtron MAMI, the beam-helicity asymmetry has been precisely measured around the energy of the Delta(1232) resonance and Q(2) = 0.2(GeV/c)(2). The results are in disagreement with three up-to-date model calculations. This is interpreted as a lack of understanding of the nonresonant background, which in dynamical models is related to the pion cloud.
Spectra and correlations of Λ andΛ¯produced in 340-GeV/cΣ−+Cand 260-GeV/cn+Cinteractions
2002
We have measured the production of strange baryons and antibaryons in 340-GeV/c Sigma /sup -/+C and 260-GeV/c n+C interactions. The single x/sub F/ distributions show the expected leading particle effect, and the single p/sub t//sup 2/ distributions show a distinct nonthermal behavior. The x/sub F/ distributions of Lambda - Lambda pairs indicate two different phase space distributions for the two coincident baryons. On the other hand two Lambda 's show identical distributions. Momentum conservation during the formation process may represent a significant source for the observed behavior.
The influence of the quarter wave plates in automated photoelasticity
2002
During the last decades, several methods have been proposed to automate photoelastic analyses. Some procedures are based on the circularly polarised light by using quarter wave plates. However, quarter wave plates are typically matched for a specific wavelength, and an error is introduced at different wavelengths. The error of quarter wave plates affects the measurement of isochromatic and isoclinic data. In this paper, the influence of the errors of quarter wave plates in some of the most common automated photoelastic methods is reviewed. The errors in the photoelastic data are given and the procedures to reduce, or eliminate, them are also suggested.
The design of a cascaded 800 MeV normal conducting C.W. race track microtron
1976
Abstract A c.w. electron accelerator of 820 MeV maximum output energy at 100 μ A beam current is proposed to make possible a large variety of coincidence experiments with energy electrons and photons as a future possibility of new, interesting experiments. It consists of a preaccelerator and 3 cascaded race track microtons using normal conducting rf structures. The design of this accelerator, based on detailed computational investigations of its beam dynamics and some experimental studies, is communicated and partly discussed in this paper.
High-resolution positron lifetime spectrometer with BaF2 scintillators
1987
In this communication we report on a design of a fast coincidence positron lifetime spectrometer, which is based on single crystal barium fluoride (BaF2) scintillators. A good time resolution (190ps, FWHM), combined with a high efficiency, has been obtained in the normal experimental set-up (with cathode earthed in the photo multipliers). The pile-up effect is observed to disturbe the measured lifetimes in the 180 degree geometry due to the high detection efficiency of the BaF2 scintillator.
A walk-free centroid method for lifetime measurements with pulsed beams
1978
Abstract A delayed-coincidence lifetime measurement method based on a comparison of walk-free centroids of time spectra is presented. The time is measured between the cyclotron rf signal and the pulse from a plastic scintillation detector followed by a fixed energy selection. The events to be time-analyzed are selected from the associated charge-particle spectrum of a silicon detector which is operated in coincidence with the scintillator, i.e. independently of the formation of the signal containing the time information. With this technique, with the micropulse fwhm of typically 500 to 700 ps, half-lives down to the 10 ps region can be measured. The following half-lives are obtained with th…
Entanglement degradation in the solid state: Interplay of adiabatic and quantum noise
2010
We study entanglement degradation of two non-interacting qubits subject to independent baths with broadband spectra typical of solid state nanodevices. We obtain the analytic form of the concurrence in the presence of adiabatic noise for classes of entangled initial states presently achievable in experiments. We find that adiabatic (low frequency) noise affects entanglement reduction analogously to pure dephasing noise. Due to quantum (high frequency) noise, entanglement is totally lost in a state-dependent finite time. The possibility to implement on-chip both local and entangling operations is briefly discussed.
Virtual point detector: Application to coincidence-summing correction in gamma-ray spectrometry
2009
The use of an efficiency transfer method based on the virtual point detector approximation to evaluate coincidence-summing correction values for point and volume sources was examined. The method was validated by means of a comparison with experimental efficiency determinations.
Excited states and reduced transition probabilities in Os168
2016
The level scheme of the neutron-deficient nuclide 168Os has been extended and mean lifetimes of excited states have been measured by the recoil distance Doppler-shift method using the JUROGAM \gamma-ray spectrometer in conjunction with the IKP K\"oln plunger device. The 168Os \gamma rays were measured in delayed coincidence with recoiling fusion-evaporation residues detected at the focal plane of the RITU gas-filled separator. The ratio of reduced transition probabilities B(E2;4_1^+ \rightarrow 2_1^+)/B(E2;2_1^+ \rightarrow 0_1^+) is measured to be 0.34(18), which is very unusual for collective band structures and cannot be reproduced by IBM-2 model calculations based on the SkM* energy-den…
Background radioactivity in the scaler mode technique of the Argo-YBJ detector
2011
""ARGO-YBJ is an extensive air shower detector located at the Yangbajing Cosmic Ray Laboratory (4300 ma.s.l., 606 g cm^−2 atmospheric depth, Tibet, China).. It is made by a single layer of Resistive Plate Chambers. (RPCs, total surface ~ 6700 m^2) grouped into 153 units. called “clusters”. The low energy threshold of the experiment is obtained using the ”scaler operation mode”, counting all the particles hitting the detector without reconstruction of the shower size and arrival direction. For each cluster the signals generated by these particles are put in coincidence in a narrow time window (150 ns) and read by four independent. scaler channels, giving the counting rates of channel. >= 1, …