123939432
Measurement of the radiative electron polarization in a 2.4 GeV storage ring
We have observed the existence of transverse polarization of the electron beam in the SPEAR storage ring resulting from the emission of synchrotron radiation in the magnetic field. The time constant for polarization build-up has been measured for a single circulating electron beam to be approx. 90 min and the corresponding equilibrium polarization to be approx. 0.85. These values are to be compared with the theoretical predictions of 124 min and 0.924, respectively. (AIP)
38997255
Prototype detector for ultrahigh energy neutrino detection
Abstract Necessary technical experience is being gained from successful construction and deployment of current prototype detectors to search for UHE neutrinos in Antarctica, Lake Baikal in Russia, and the Mediterranean. The prototype detectors have also the important central purpose of determining whether or not UHE neutrinos do in fact exist in nature by observation of at least a few UHE neutrino-induced leptons with properties that are not consistent with expected backgrounds. We discuss here the criteria for a prototype detector to accomplish that purpose in a convincing way even if the UHE neutrino flux is substantially lower than predicted at present.
118712243
Comments on the letter «Limits on the electromagnetic production of heavy leptons»
123899161
NEUTRINOS AND MUONS IN AREA 1.
118973535
Some Recent Advances in Neutrino Physics
One answer to questions concerning the subject matter of elementary particle physics and its position within the physical sciences is that particle physics is the study of creation. To justify this idea, at least in part, consider the “big bang” model of creation of the universe. In that model the primeval fireball involved very high temperatures, estimated to be greater than 1011 degrees Kelvin (°K), which is to be compared with the interior temperature of the sun at about 107 degrees Kelvin. We believe the sun to be a nuclear furnace, generating its energy by individual nuclear interactions in the million electron volt (MeV) energy range. In the “big bang” the energies involved in the individual particle interactions would have been more than 104 times larger than in the sun, and thus in the tens of giga-electron volts (GeV). This is precisely the energy region of present-day high energy or elementary particle physics laboratory experiments. In this sense, then, laboratory experiments that study, even indirectly, lepton-lepton scattering or quark-quark interactions are revisiting creation.
121246612
Scaling-variable distributions in high-energy inelastic neutrino interactions
53361667
Use of single photon counting detector arrays in combined PET/MR: Characterization of LYSO-SiPM detector modules and comparison with a LSO-APD detector
We propose in this study a novel PET detector concept as insert for simultaneous PET/MR imaging, using arrays of Silicon Photomultipliers (SiPMs) as photodetectors, read out by a data acquisition system based on sampling ADCs. A 2 × 2 LSO-SiPM detector array and four single channel LYSO-SiPM detectors have been evaluated and compared to a LSO-APD detector. A 17.9% energy resolution and a 1.4 ns time resolution have been measured. No degradation of these values could be detected when simultaneous MR acquisitions were performed. The non-linear detector behaviour due to the limited dynamic range and recovery time effects has been studied. In addition, the contribution of dark counts and optical crosstalk for PET applications was also addressed. The feasibility for position localization of the incident light to a SiPM array using Anger logic has been investigated.
122236095
APPROACH TO THE NUCLEAR MANY-BODY PROBLEM BY A VARIATIONALLY DETERMINED TRANSFORMATION.
118729996
K- p amplitudes near the lambda(1520)
15829252
Factorization of analytic representations in the unit disc and number-phase statistics of a quantum harmonic oscillator
The inner - outer part factorization of analytic representations in the unit disc is used for an effective characterization of the number-phase statistical properties of a quantum harmonic oscillator. It is shown that the factorization is intimately connected with the number-phase Weyl semigroup and its properties. In the Barut - Girardello analytic representation the factorization is implemented as a convolution. Several examples are given which demonstrate the physical significance of the factorization and its role for quantum statistics. In particular, we study the effect of phase-space interference on the factorization properties of a superposition state.
39771192
Quantum statistical properties of the radiation field in a cavity with a movable mirror
A quantum system composed of a cavity radiation field interacting with a movable mirror is considered and quantum statistical properties of the field are studied. Such a system can serve, in principle, as an idealized meter for detection of a weak classical force coupled to the mirror which is modelled by a quantum harmonic oscillator. It is shown that the standard quantum limit on the measurement of the mirror position arises naturally from the properties of the system during its dynamical evolution. However, the force detection sensitivity of the system falls short of the corresponding standard quantum limit. We also study the effect of the nonlinear interaction between the moving mirror and the radiation pressure on the quadrature fluctuations of the initially coherent cavity field.