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261.
It has been shown by Yu. M. Golubev, M. I. Kolobov, and I. V. Sokolov, Zh. éksp. Teor. Fiz. 111, 1579 (1997) [JETP 84, 864 (1997)], that when an optical cavity is excited by external radiation from a sub-Poisson laser the cavity mode may be
in either a sub-Poisson or a Poisson stationary state. This is not important for a resonant medium which is excited into the
upper laser level while interacting with this mode inside the cavity. The degree of regularity of the excitation will be identical
to that of the initial light flux incident on the cavity, and this ultimately ensures the same sub-Poisson lasing as for strictly
regular pumping of the resonant medium.
Zh. éksp. Teor. Fiz. 113, 1223–1234 (April 1998) 相似文献
262.
A. Sánchez-Lavega A. Salazar A. Ocariz L. Pottier E. Gomez L.M. Villar E. Macho 《Applied Physics A: Materials Science & Processing》1997,65(1):15-22
Received: 16 September 1996/Accepted: 6 January 1997 相似文献
263.
264.
265.
266.
We discuss the possible new electroweak interactions which may be generated by the Higgs sector at the scale of theZ mass. For this purpose, we give a set ofSU(2)×U(1) gauge invariant operators constructed in terms ofW, Z, γ and Higgs fields which in the unitary gauge describe all possible γWW andZWW anomalous couplings. The dimension of these operators varies from 6 to 12. This fact allows us to consider various scenaria for the manifestations of the New Physics. We conclude that the underlying dynamics induced by the Higgs sector can be tested through a model-independent amplitude analysis of gauge boson pair production at LEP2 and future colliders. 相似文献
267.
268.
G. Garcia-Belmonte J. Bisquert L. M. Navarro J. R. Jurado F. M. B. Marques 《Ionics》1995,1(5-6):377-383
In ionic conductors, long range-migrating charges are a main cause of polarization processes. This has complicated, up to
date, the study of ionic thermocurrents (ITC) in solid electrolytes. However, the method is appealing, as it probes directly
charge-formation phenomena that are important both from a scientific point of view and for applications.
This work reports on the observation of ITC in solid electrolytes. Under appropriate experimental conditions, the ITC response
of a zirconia sample electroded with platinum is a reproducible one, thus opening the way to a new characterization method
that may complement other well established methods, such as Impedance Spectroscopy and a number of electrochemical techniques.
The general trends of the response, which is composed of two well resolved ITC peaks, is discussed. One of them, taking place
at higher temperatures, conforms to the standard shape of a first order kinetics depolarization process.
Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, Sept. 10–16, 1995 相似文献
269.
270.
ALEPH Collaboration D. Buskulic D. Casper I. De Bonis D. Decamp P. Ghez C. Goy J. -P. Lees A. Lucotte M. -N. Minard et al. 《Zeitschrift fur Physik C Particles and Fields》1995,69(1):379-392
A data sample of about 3.0 million hadronicZ decays collected by the ALEPH experiment at LEP in the years 1991 through 1994 is used to make an inclusive selection of
B hadron events. In this event sample 4227±140±252B* mesons in the decayB*→Bγ and 1944±108±161B**
u,d
mesons decaying into a B meson and a charged pion are reconstructed. Here and in the followingB**
u,d
denotes the eightL=1(bū) and (bd) states and their charge conjugate.
For the well establishedB* meson the following quantities are obtained:ΔM=M
B*−MB=(45.30±0.35±0.87) MeV/c2 andN
B*/(N
B+N
B*)=(77.1±2.6±7.0)%. The angular distribution of the photons in theB* rest frame is used to measure the relative contribution of longitudinalB* polarization states to beσ
L/(σ
L+σ
T)=(33±6±5)%. 相似文献