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981.
S.?J?ger 《The European Physical Journal C - Particles and Fields》2009,59(2):497-520
We review the sources and phenomenology of non-minimal flavor violation in the MSSM. We discuss in some detail the most important
theoretical and experimental constraints, as well as promising observables to look for supersymmetric effects at the LHC and
in future experiments. We emphasize the sensitivity of flavor physics to the mechanism of supersymmetry breaking and to new
degrees of freedom present at fundamental scales, such as the grand unification scale. We include a discussion of present
data that may hint at departures from the standard model. 相似文献
982.
?. Ate? G. Tekeli G. ?elik E. Ak?n M. Ta?er 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(1):21-24
The electric dipole oscillator strengths for multiplet and
individual lines between some doublet and quartet levels have been
calculated using the weakest bound electron potential model theory (WBEPMT)
in singly ionized oxygen. We employed both numerical Coulomb approximation
(NCA) wave functions and numerical non-relativistic Hartree-Fock (NRHF) wave
functions for expectation values of radii in determination of parameters.
The calculated oscillator strengths have been compared with available
theoretical and experimental results. A good agreement with results in
literature has been obtained. Moreover, oscillator strengths not existing in
the literature for some highly excited levels have been obtained using this
method.
Electronic supplementary material Supplementary Online Material 相似文献
983.
A. Gaál I. Bugár I. Capek L. Fialová T. Pálszegi V. Sz?cs A. ?atka F. Uherek 《Laser Physics》2009,19(5):961-968
Time-resolved femtosecond multicolor absorption spectroscopy of silver nanoparticle (NP) colloids with particle diameter in range of 10–30 nm is presented. The amplified femtosecond excitation of the surface plasmon resonance band resulted in transient absorption spectra reflecting the electron-phonon relaxation dynamics, which takes place on the early picosecond time scale. The monitored band with enhanced absorption in the 490–540 nm spectral range exhibited red-shift with increasing pump fluency from 0.4 mJ/cm2 to the 1.5 mJ/cm2 level. The growth of the relaxation time with increasing pump fluency reveals the temperature dependent relaxation dynamics caused by the nanometer sized electron confinement in the case of silver. This effect was confirmed also by identification of the relaxation time dependence on the particle diameter at constant pump fluency. The complex experimental results revealed nonlinearities both in the laser excitation and electron relaxation processes. 相似文献
984.
We introduce a newfamily of C
2-cofinite N = 1 vertex operator superalgebras , m ≥ 1, which are natural super analogs of the triplet vertex algebra family , p ≥ 2, important in logarithmic conformal field theory. We classify irreducible -modules and discuss logarithmic modules. We also compute bosonic and fermionic formulas of irreducible characters. Finally, we contemplate possible connections between the category of -modules and the category of modules for the quantum group , , by focusing primarily on properties of characters and the Zhu’s algebra . This paper is a continuation of our paper Adv. Math. 217, no.6, 2664–2699 (2008).
The second author was partially supported by NSF grant DMS-0802962. 相似文献
985.
Yangjian Cai Q. Lin H. T. Eyyubo?lu Y. Baykal 《Applied physics. B, Lasers and optics》2009,94(2):319-325
The propagation of an elliptical Gaussian beam (EGB) through an astigmatic ABCD optical system in a turbulent atmosphere is
investigated. An analytical formula for the average intensity of an EGB and a generalized tensor ABCD law for the generalized
complex curvature tensor are derived. As an application example, we derived an analytical formula for the average intensity
of an elliptical flat-topped beam propagating through an astigmatic ABCD optical system in a turbulent atmosphere. As a numerical
example, the focusing properties of an EGB focused by a thin lens in a turbulent atmosphere are studied. It is found that
the focused beam at the focal plane becomes a circular Gaussian beam when the atmospheric turbulence is strong enough, and
the beam width of the circular Gaussian beam is determined by atmospheric turbulence strength, focal length of the thin lens,
and wavelength of the initial beam but is independent of the initial beam widths (i.e., initial intensity distribution). 相似文献
986.
S. Ertman A. Czapla T. R. Woliński T. Nasi?owski H. Thienpont E. Nowinowski-Kruszelnicki R. D?browski 《Opto-Electronics Review》2009,17(2):150-155
Photonic liquid crystal fibers have already been demonstrated as a promising perspective for creation of new classes of dynamically
tunable optical fiber devices. By combining different geometries of photonic crystal fibers with a variety of different liquid
crystals it is possible to obtain a new generation of fibers with dynamically tunable properties, e.g., transmission spectra,
attenuation or dispersion.
In this paper, tunable birefringence in a commercially available highly birefringent Blazephotonics PM-1550-01 photonic crystal
fiber selectively filled with a low birefringence liquid crystal has been experimentally demonstrated. Theses experimental
results have been compared with simulations based on the multipole method. 相似文献
987.
Andrzej Graja Iwona Olejniczak Boles?aw Barszcz John A. Schlueter 《Central European Journal of Physics》2009,7(4):663-667
Infrared and Raman investigations of two phases of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) based organic conductors
with the same CF3CF2SO3− anion: β′-(BEDT-TTF)2CF3CF2SO3 and δ′-(BEDT-TTF)2CF3CF2SO3, are shortly reviewed and compared with the most typical infrared properties of the family of (BEDT-TTF)2RR′SO3 organic conductors, where R = SF5, CF3, and R′ are CH2, CF2, CHF, CHFCF2, and CH2CF2. The role of the molecular structur and spatial organization of the counterions is discussed.
Presented at 2-nd International Conference on Functional Materials and Devices, ICFMD 2008, June 16–19, 2008, Kuala Lumpur,
Malaysia 相似文献
988.
S. Petrovi? B. Gakovi? D. Peru?ko T. Desai D. Batani M. ?ekada B. Radak M. Trtica 《Laser Physics》2009,19(8):1844-1849
Interaction of an Nd:YAG laser, operating at 532 nm wavelength and pulse duration of 40 ps, with tungsten-titanium (WTi) thin film (thickness, 190 nm) deposited on single silicon (100) substrate was studied. Laser fluences of 10.5 and 13.4 J/cm2 were found to be sufficient for modification of the WTi/silicon target system. The energy absorbed from the Nd:YAG laser beam is partially converted to thermal energy, which generates a series of effects, such as melting, vaporization of the molten material, shock waves, etc. The following WTi/silicon surface morphological changes were observed: (i) ablation of the thin film during the first laser pulse. The boundary of damage area was relatively sharp after action of one pulse whereas it was quite diffuse after irradiation with more than 10 pulses; (ii) appearance of some nano-structures (e.g., nano-ripples) in the irradiated region; (iii) appearance of the micro-cracking. The process of the laser interaction with WTi/silicon target was accompanied by formation of plasma. 相似文献
989.
Set-valued dynamic systems and random iterations of set-valued weaker contractions in uniform spaces
K. W?odarczyk C. Obczyński D. Wardowski 《Journal of Mathematical Analysis and Applications》2006,318(2):772-780
Set-valued weaker contractions in uniform, locally convex and metric spaces are defined and dynamic systems of such weaker contractions are studied. Conditions guaranteeing the convergence of generalized sequences of random iterations and iterations and the existence and uniqueness of endpoints of set-valued weaker contractions are established. Our definitions and results are new for set-valued maps in uniform, locally convex and metric spaces and even for single-valued maps. 相似文献
990.
Dragana S. Cvetkovi?-Ili? Dragan S. Djordjevi? Yimin Wei 《Linear algebra and its applications》2006,418(1):53-61
In this paper we investigate additive properties of the generalized Drazin inverse in a Banach algebra. We find some new conditions under which the generalized Drazin inverse of the sum a + b could be explicitly expressed in terms of a, ad, b, bd. Also, some recent results of Castro and Koliha [New additive results for the g-Drazin inverse, Proc. Roy. Soc. Edinburgh Sect. A 134 (2004) 1085-1097] are extended. 相似文献