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21.
N. Beverini G. Carelli A. De Michele M. Finotti N. Ioli A. Moretti 《Applied physics. B, Lasers and optics》2003,77(1):93-95
By means of a new CO2 laser we performed a new investigation of the far-infrared laser emission spectrum of hydrazine excited by the 10P(32) and 10R(8) CO2 laser lines. We found seven new lines and measured the frequency of four of them; moreover we measured the frequencies of two more lines previously reported in the literature with only wavelength measurements. The frequencies of the far-infrared laser emissions have been measured by means of a frequency-synthesis chain based on new InP Schottky diodes. The detected signal was beat-note generated in a Schottky diode between the far-infrared radiation, the harmonics of a 72 GHz frequency reference and a rf signal. We also characterized all of the observed lines by their polarization relative to the pumping CO2 laser, the optimum pressure and the offset relative to the CO2 center frequency. PACS 42.55.Lt; 42.62.Fi 相似文献
22.
We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the
one of the top quark, at future Linear Colliders operating in mode at the TeV energy scale. Final states with one or two bosons are considered, as produced by both tree- and loop-level interactions.
Received: 8 November 2002 / Revised version: 12 February 2003 / Published online: 13 May 2003
RID="a"
ID="a" e-mail: stefano.moretti@cern.ch
RID="b"
ID="b" e-mail: kanemu@post.kek.jp 相似文献
23.
We use tools of the equilibrium statistical mechanics of disordered systems to study analytically the statistical properties of an ecosystem composed of N species interacting via random mutual interactions, as well as via deterministic self-interactions of order p>/=2. We show that the main effect of increasing the order of the interactions among the species is to make the system less competitive, in the sense that the fraction of extinct species is greatly reduced. In addition, we find that for p>2 there is a threshold value which gives a lower bound to the concentration of the surviving species, preventing then the existence of rare species and, consequently, increasing the robustness of the ecosystem to external perturbations. 相似文献
24.
B. Vincent R. Kremer A. Boudrioua P. Moretti Y.-C. Zhang C.-C. Hsu L.-H. Peng 《Applied physics. B, Lasers and optics》2007,89(2-3):235-239
An optical planar waveguide is investigated in ZnO-doped periodically poled lithium niobate formed by He+ implantation. Optical losses were found to be 2 dB/cm. Second-harmonic generation is used to produce a green laser beam by
quasi-phase matching in the obtained waveguide. The conversion efficiency was found to be 10-2%/W. Photorefractive resistance properties are reported and discussed relating to un-doped periodically poled lithium niobate.
PACS 42.65.-k; 42.65.Wi; 42.82.-m 相似文献
25.
26.
27.
In the NMSSM, because of introducing a complex singlet superfield, the lightest CP-odd Higgs boson, a
1, can be a singlet-like state with a tiny doublet component in large regions of parameter space. In this paper, we examine
the discovery potential of a
1 produced in association with a bottom–antibottom pair at the LHC through τ
+
τ
− and γγ decay modes. It is shown that an a
1 with mass ≤M
Z
can be extracted from the SM backgrounds by using the τ
+
τ
− decay channel, a possibility precluded to the MSSM. In contrast, the γγ decay mode is overwhelmed by backgrounds despite the fact that the branching ratio of this mode can reach unity when a
1 is a pure singlet. 相似文献
28.
The effect of tributyltin‐chloride (TBTC), dibutyltin‐chloride (DBTC) and monobutyltin‐chloride (MBTC) on rainbow trout (Salmo irideus) nuclear DNA, was investigated by means of single cell gel electrophoresis (‘comet’ assay). Our data show that TBTC presents a marked genotoxic effect, whereas the genotoxic effect is less pronounced for DBTC and it is completely absent for MBTC. These results could be important in evaluating the environmental risks deriving from the use of these molecules as a antifouling agents in marine paints and as agricultural biocides. Copyright © 2001 John Wiley & Sons, Ltd.
Abbreviations:
-
- TBTC,
-
- tributyltin‐chloride;
-
- DBTC,
-
- dibutyltin‐chloride;
-
- MBTC,
-
- monobutyltin‐chloride;
-
- Hb,
-
- hemoglobin.
29.
A. De Michele K. Bousbahi G. Carelli A. Moretti 《International Journal of Infrared and Millimeter Waves》2003,24(10):1649-1654
We have investigated CHD2OH methanol as source of far-infrared (FIR) laser radiation using the optical pumping technique. Our new waveguide pulsed CO2 laser, with peak powers as high as some kW, has allowed us to observe 12 new lines. Each of them is characterized in wavelength, relative polarization, intensity, optimum operating pressure and pump offset from the center of the exciting CO2 line. 相似文献
30.
Sonia Mazzucchi Valter Moretti Ivan Remizov Oleg Smolyanov 《Mathematische Nachrichten》2023,296(3):1244-1284
Chernoff approximations of Feller semigroups and the associated diffusion processes in Riemannian manifolds are studied. The manifolds are assumed to be of bounded geometry, thus including all compact manifolds and also a wide range of non-compact manifolds. Sufficient conditions are established for a class of second order elliptic operators to generate a Feller semigroup on a (generally non-compact) manifold of bounded geometry. A construction of Chernoff approximations is presented for these Feller semigroups in terms of shift operators. This provides approximations of solutions to initial value problems for parabolic equations with variable coefficients on the manifold. It also yields weak convergence of a sequence of random walks on the manifolds to the diffusion processes associated with the elliptic generator. For parallelizable manifolds this result is applied in particular to the representation of Brownian motion on the manifolds as limits of the corresponding random walks. 相似文献