43335620
The Universal Fermi Interaction and the Conserved Vector Current in Beta Decay
The theoretical formulation of the (V-- A) fermi interac tion is shown. The requirements of the continuity equatio of the electromagnetic current are discussed in order to lead to the formulation of the conserved vector current theory and the unique properties arising from it. The present status of the question of equality between the vector coupling constant g/sub v/ of beta decay and the Fermi constant g/sub u/ of mu decay is examined. Four types of experiments to test the CVC hypothesis are discussed. (auth) O H21308 A procedure was developed for measuring photoneutron yields from targets of grent thickness by the method of induced activity. The dependence of the photoneutron yields on the electron energy, on /sup 16/O nuclei over an energy range of 19 to 66 Mev, and on /sup 63/Cu nuclei over an energy range of 13 to 50 Mev was investigated. The electron beam from a linear accelerator was monitored by means of a secondary emission monitor. The measured values of the photoneutron yields agree with the data of others; they proved to be haif the calculated values obtained by means of the Belenky-Tamm equilibrium spectrum. (auth)
126195733
Double beta decay‐an experimental review
In this review, a brief discussion on the experimental objectives and theoretical conceptions of the neutrinos was introduced. Two different types of experimental methods and their results were presented and discussed.
121100619
NEW HIGH ACCURACY MEASUREMENT OF THE PIONIC MASS
The pionic x-ray energies of the 4f-3d transition in ..pi..-P and the 5f-4d transition in ..pi..-Ti were measured with a bent-crystal spectrometer at the Nevis synchrocyclotron; and a new value of the pionic mass is deduced to be 139567.5 +- 0.9 keV, leading to an improved value for the ..mu..-neutrino mass of m..nu../sub ..mu..//sup 2/=0.102 +- 0.119 MeV/sup 2/; m..nu../sub ..mu../<0.52 MeV, at 90% confidence level.
120538673
A streamer chamber used in a search for double beta decay
Abstract A 53 cm dia., 8 cm deep helium-filled streamer chamber is described. At a field strength of 6.2 kV/cm, streamers extend over the entire space between the plates of the chamber and the particle track is shown by bright, narrow regions in the streamers. The mechanism of electrical breakdown in this mode of operation and other modes was investigated. The streamer theory of Raether correctly predicts breakdown-time and dead-space. Penning effect by impurities in the chamber gas appears to influence discharge development significantly at the low field strengths used in track-projecting chambers but not at the high field strengths used in streamer chambers.
120646099
MUONIC ATOMS. I. DYNAMIC HYPERFINE STRUCTURE IN THE SPECTRA OF DEFORMED NUCLEI.
29674729
Relation between the kinematic and dynamic moments of inertia in superdeformed nuclei.
The relation between the kinematic and dynamic moments of inertia, {ital scrJ}{sup (1)} and {ital scrJ}{sup (2)}, was analyzed for the normally deformed and superdeformed rotational bands. According to the {ital ab} expression for rotational spectrum, {ital E}({ital I})={ital a}( {radical}1+{ital bI}({ital I}+1) {minus}1), the ratio {ital R}= {radical}({ital scrJ}{sup (1)}){sup 3}/{ital scrJ}{sup (2)} should be {ital I} independent. Extensive analyses for the normally deformed rotational bands in the rare-earth and actinide nuclei show that the {ital R}'s do remain {ital I} independent. The same relation holds well for the superdeformed bands observed in the {ital A}{similar to}190 region, and seems also to hold for those in the {ital A}{similar to}150 region, if spin assignments are made correctly. The {ital I} independence of {ital R} provides an additional support to the spin assignments.
120491282
Accessibility of the stochastic gravitational wave background from magnetars to the interferometric gravitational wave detectors
118829599
Negative power spectra in quantum field theory
Abstract We consider the spatial power spectra associated with fluctuations of quadratic operators in field theory, such as quantum stress tensor components. We show that the power spectrum can be negative, in contrast to most fluctuation phenomena where the Wiener–Khinchin theorem requires a positive power spectrum. We show why the usual argument for positivity fails in this case, and discuss the physical interpretation of negative power spectra. Possible applications to cosmology are discussed.
117599682
Quantum fluctuations of the stress tensor
119279483
Gravity Waves from Quantum Stress Tensor Fluctuations in Inflation
We consider the effects of the quantum stress tensor fluctuations of a conformal field in generating gravity waves in inflationary models. We find a non-scale invariant, non-Gaussian contribution which depends upon the total expansion factor between an initial time and the end of inflation. This spectrum of gravity wave perturbations is an illustration of a negative power spectrum, which is possible in quantum field theory. We discuss possible choices for the initial conditions. If the initial time is taken to be sufficiently early, the fluctuating gravity waves are potentially observable both in the CMB radiation and in gravity wave detectors, and could offer a probe of transplanckian physics. The fact that they have not yet been observed might be used to constrain the duration and energy scale of inflation.
53600200
Nonequilibrium dynamics of moving mirrors in quantum fields : Influence functional and the Langevin equation
We employ the Schwinger-Keldysh formalism to study the nonequilibrium dynamics of the mirror with perfect reflection moving in a quantum field. In the case where the mirror undergoes the small displacement, the coarse-grained effective action is obtained by integrating out the quantum field with the method of influence functional. The semiclassical Langevin equation is derived, and is found to involve two levels of backreaction effects on the dynamics of mirrors: radiation reaction induced by the motion of the mirror and backreaction dissipation arising from fluctuations in quantum field via a fluctuation-dissipation relation. Although the corresponding theorem of fluctuation and dissipation for the case with the small mirror's displacement is of model independence, the study from the first principles derivation shows that the theorem is also independent of the regulators introduced to deal with short-distance divergences from the quantum field. Thus, when the method of regularization is introduced to compute the dissipation and fluctuation effects, this theorem must be fulfilled as the results are obtained by taking the short-distance limit in the end of calculations. The backreaction effects from vacuum fluctuations on moving mirrors are found to be hardly detected while those effects from thermal fluctuations may be detectable.