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A model of neutrino mass and dark matter with large neutrinoless double beta decay

We propose a model where neutrino masses are generated at three loop order but neutrinoless double beta decay occurs at one loop. Thus we can have large neutrinoless double beta decay observable in the future experiments even when the neutrino masses are very small. The model receives strong constraints from the neutrino data and lepton flavor violating decays, which substantially reduces the numb

High-order harmonic generation in strong laser fields

The recent advances concerning high-order harmonic generation processes in strong laser fields are discussed. We show how the width of the plateau inherent to the production of high harmonics varies with the pulse width, the laser wavelength and the atomic medium. Phase matching effects are discussed in terms of coherence length owing to the laser focusing. Finally, we show that the idea of genera

Multiply charged ions formed by multiphoton absorption processes in the continuum

Singly, doubly, triply, and quadruply charged krypton ions are formed by multiphoton absorption processes in krypton atoms. They are induced by a 50-psec laser pulse at 1.064 m in the 1013-1014-W-cm-2 intensity range. The percentage ratio between the numbers of doubly and singly ionized Kr atoms is 10% at 8×1013 W cm-2. It is shown that Kr2+ ions result from a direct 33-photon absorption process.

Theory of resonant multiphoton ionization of krypton by intense ultraviolet laser radiation

We present a theoretical interpretation of the experimental results on three-photon-resonant four-photon ionization of Kr reported by Landen, Perry, and Campbell [Phys. Rev. Lett. 59, 2558 (1987)] and Perry and Landen [Phys. Rev. A 38, 2815 (1988)]. Our calculations are based on multichannel quantum-defect theory combined with a density-matrix formalism describing the spatiotemporal development of

Influence of ellipticity on harmonic generation

We present results of experiments testing the influence of elliptical polarization on the production of high-order harmonics. Experiments were conducted both with a 600-nm, 1-psec dye laser and with an 825-nm, 140-fsec Cr:LiSAF6 (Cr:LiSAF) laser system, over a wide range of intensities and target gases (xenon, argon, and neon), using a detection system with a dynamical range of more than three ord

Deferred imitation, associative memory and communication in 14-month-old children

The presentation will build on two recent studies that combine behavioral observations of memory (deferred imitation, DI), electrophysiological (Event-Related Potentials, ERP) measures of associative memory and parental reports of language in 14-monthsold children. In both studies, an ERP (Nc) response indicating associative memory as well as a correlation between Nc and DI was observed. Further a

Low frequencies of supernormal clutches in the Southern Dunlin and the Temminck’s Stint

Supernormal clutches are found across bird species. Such clutches often result from more than one female laying eggs in the same nest and can reflect different behaviours from parasitism to laying mistakes. Enlarged clutches are readily visible among waders due to a maximum maternal clutch size of four eggs, yet surprisingly little is known about this phenomenon. Since supernormal clutches are rar

The importance of mineral determinations to PROFILE base cation weathering release rates : A case study

Accurate estimates of base cation weathering rates in forest soils are crucial for policy decisions on sustainable biomass harvest levels and for calculations of critical loads of acidity. The PROFILE model is one of the most frequently used methods to quantify weathering rates, where the quantitative mineralogical input has often been calculated by the A2M ("Analysis to Mineralogy") program base

Introduction

This volume is a collection of articles dealing with a question of Jewish involvement in the interfaith and intercultural dialogue in the postwar Europe, Israel and the United States. Jewish relation to alterity is seen from a few different methodological standpoints: historical, sociological, theological and literary.

S3 flavored left-right symmetric model of quarks

We construct a model based on the electroweak gauge group SU(2)L×SU(2)R×U(1)B-L augmented by an S3 symmetry. We assign nontrivial S3 transformation properties to the quarks, and consequently we need two scalar bidoublets. Despite the extra bidoublet, we have only six Yukawa couplings thanks to the discrete symmetry. Diagonalization of the quark mass matrices shows that at the leading order only th

2HDM without FCNC : off the beaten tracks

We propose an alternative method of constructing two Higgs-doublet models free from scalar mediated FCNC couplings at the tree-level. In a toy scenario, we have presented semi realistic textures for the Yukawa matrices, which can reproduce the approximate flavor structure in the quark sector. Presence of flavor diagonal but nonuniversal Yukawa couplings emerges as a distinguishing feature of such

S3 symmetry and the quark mixing matrix

We impose an S3 symmetry on the quark fields under which two of three quarks transform like a doublet and the remaining one as singlet, and use a scalar sector with the same structure of SU(2) doublets. After gauge symmetry breaking, a Z2 subgroup of the S3 remains unbroken. We show that this unbroken subgroup can explain the approximate block structure of the CKM matrix. By allowing soft breaking

Linear and nonlinear screening effects in two-photon ionization of xenon

We apply the random-phase approximation to two-photon ionization. We develop a formalism which, by means of screened electron-photon interactions, includes the nonlinear response and, in particular, double-excitation processes. The theory is illustrated by numerical calculations of the two-photon ionization cross section of the external (5p and 5s) shell of xenon, over a large energy range: from t

Phase-matching effects in strong-field harmonic generation

We present experimental results of harmonic generation at 1064 nm using a 36-ps neodymium-doped yttrium aluminum garnet laser tightly focused in a gas jet of xenon. The harmonic yields are studied as a function of the position of the focus in the jet at several laser intensities and as a function of intensity at several focus positions. These results bring information about how the high harmonics