122242130
Collision quenching of the metastable 2S state of muonic hydrogen and the muonic helium ion
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.
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.
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.
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.
119488774
Quantum fluctuations of radiation pressure
Quantum fluctuations of electromagnetic radiation pressure are discussed. We use an approach based on the quantum stress tensor to calculate the fluctuations in velocity and position of a mirror subjected to electromagnetic radiation. Our approach reveals that radiation pressure fluctuations in the case of a coherent state are due to a cross term between vacuum and state dependent terms in a stress tensor operator product. Thus observation of these fluctuations would entail experimental confirmation of this cross term. We first analyze the pressure fluctuations on a single, perfectly reflecting mirror, and then study the case of an interferometer. This involves a study of the effects of multiple bounces in one arm, as well as the correlations of the pressure fluctuations between arms of the interferometer. In all cases, our results are consistent with those previously obtained by Caves using different methods. We argue that the agreement between the different methods supports the reality of the cross term and justifies the methods used in its evaluation.
124998001
Nonequilibrium backreaction on a moving charge and mirror in quantum fields
14403021
Fluctuations of the Hawking flux
The fluctuations of the flux radiated by an evaporating black hole will be discussed. Two approaches to this problem will be adopted. In the first, the squared flux operator is defined by normal ordering. In this case, both the mean flux and the mean squared flux are well defined local quantites. It is shown that the flux undergoes large fluctuations on a time scale of the order of the black hole's mass. Thus the semiclassical theory of gravity, in which a classical gravitational field is coupled to the expectation value of the stress tensor, breaks down below this time scale. In the second approach, one does not attempt to give meaning to the squared flux as a local quantity, but only as a time-averaged quantity. In both approaches, the mean squared mass minus the square of the mean mass grows linearly in time, but four times as fast in the second approach as in the first.
119118161
Quantum noise in the mirror-field system: A field theoretic approach
Abstract We revisit the quantum noise problem in the mirror–field system by a field-theoretic approach. Here a perfectly reflecting mirror is illuminated by a single-mode coherent state of the massless scalar field. The associated radiation pressure is described by a surface integral of the stress-tensor of the field. The read-out field is measured by a monopole detector, from which the effective distance between the detector and mirror can be obtained. In the slow-motion limit of the mirror, this field-theoretic approach allows to identify various sources of quantum noise that all in all leads to uncertainty of the read-out measurement. In addition to well-known sources from shot noise and radiation pressure fluctuations, a new source of noise is found from field fluctuations modified by the mirror’s displacement. Correlation between different sources of noise can be established in the read-out measurement as the consequence of interference between the incident field and the field reflected off the mirror. In the case of negative correlation, we found that the uncertainty can be lowered than the value predicted by the standard quantum limit. Since the particle-number approach is often used in quantum optics, we compared results obtained by both approaches and examine its validity. We also derive a Langevin equation that describes the stochastic dynamics of the mirror. The underlying fluctuation–dissipation relation is briefly mentioned. Finally we discuss the backreaction induced by the radiation pressure. It will alter the mean displacement of the mirror, but we argue this backreaction can be ignored for a slowly moving mirror.
119211117
Trapping effects on inflation
We develop a Lagrangian approach based on the influence functional method so as to derive self-consistently the Langevin equation for the inflaton field in the presence of trapping points along the inflaton trajectory. The Langevin equation exhibits the backreaction and the fluctuation-dissipation relation of the trapping. The fluctuation is induced by a multiplicative colored noise that can be identified as the the particle number density fluctuations and the dissipation is a new effect that may play a role in the trapping with a strong coupling. In the weak coupling regime, we calculate the power spectrum of the noise-driven inflaton fluctuations for a single trapping point and studied its variation with the trapping location. We also consider a case with closely spaced trapping points and find that the resulting power spectrum is blue.