120646099
MUONIC ATOMS. I. DYNAMIC HYPERFINE STRUCTURE IN THE SPECTRA OF DEFORMED NUCLEI.
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.
118741981
Delta I=1 staggering in odd superdeformed nuclei
The {Delta}I=1 staggering in odd superdeformed nuclei in the A{approximately}190 region is systematically investigated. Most of the signature partners in this region show large-amplitude staggerings. The behavior is analyzed and parametrized in the conventional collective model. The spins of the signature partner pairs are assigned in a modified ab expression. {copyright} {ital 1997} {ital The American Physical Society}
121147087
The Angular Correlation of Scattered Annihilation Radiation
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.
119479826
Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations
We discuss the effect of quantum stress tensor fluctuations in de Sitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in de Sitter spacetime, and find that this effect tends to grow, in contrast to the situation in flat spacetime. This growth potentially leads to observable consequences in inflationary cosmology in the form of density perturbations which depend upon the duration of the inflationary period. In the context of our model, the effect may be used to place upper bounds on this duration.
117599682
Quantum fluctuations of the stress tensor
119185780
Quantum Stress Tensor Fluctuations of a Conformal Field and Inflationary Cosmology
We discuss the additional perturbation introduced during inflation by quantum stress tensor fluctuations of a conformally invariant field such as the photon. We consider both a kinematical model, which deals only with the expansion fluctuations of geodesics, and a dynamical model which treats the coupling of the stress tensor fluctuations to a scalar inflaton. In neither model do we find any growth at late times, in accordance with a theorem due to Weinberg. What we find instead is a correction which becomes larger the earlier one starts inflation. This correction is non-Gaussian and highly scale dependent, so the absence of such effects from the observed power spectra may imply a constraint on the total duration of inflation. We discuss different views about the validity of perturbation theory at very early times during which currently observable modes are trans-Planckian.
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.
124998001
Nonequilibrium backreaction on a moving charge and mirror in quantum fields