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Clouds are a macroscopic and easily observable natural phenomenon (a suspension of water droplets or ice crystals), which has been studied since the dawn of modern science. Clouds raise increasing interest in the scientific community, due to their fundamental role in the water cycle, energy balance, and climate. The atmosphere, however, contains other suspended particles that constitute the atmospheric aerosol, which also play an important role in the Earth's radiative balance. Moreover, they have a major impact on the formation, evolution, and characteristics of clouds. Study and quantification of clouds and aerosol often requires discriminating from each other. Although in general they differ in the proportion of water (liquid or solid), composition, size, shape, etc., there are situations that lie in the border between them (hydrated aerosols, haze, dissipating clouds, etc.) This communication reviews several studies that suggest that clouds and aerosol should be treated as a continuum or that an additional phase between them must be considered. Both observational works of this transition zone and studies that deal with the radiative effect of these transition situations are commented. We conclude that it is important to carry out additional research focused on suspensions of particles with characteristics between those of typical clouds and those of pure aerosol. [ABSTRACT FROM AUTHOR]

This paper reports the spectroscopic properties of praseodymium-doped potassium lutetium double phosphates, KLuP2O7:Pr3+(1%). Spectra of photoluminescence (PL), PL excitation, X-ray excited luminescence and pulse cathodoluminescence, thermally stimulated luminescence were measured. KLuP2O7:Pr3+ showed Pr3+ emission connected both with high intensity interconfigurational 4f15d1→4f2 transitions (UV bands in region of 250-320 nm), intraconfigurational 4f2→4f2 transitions (weak lines in vision spectral region) and Stocks defect-related luminescence. Upon both UV intra-center and band-to-band excitation with ionizing radiation, emission spectra of KLuP2O7:Pr3+ are dominated by Pr3+ interconfigurational 4f1 5d1→4f2 radiative transitions. Luminescence decay kinetics measurements established decay time τ ≈ 19 ns at room temperature. The study of thermally stimulated luminescence demonstrates effective light storage. Parameters of charge carriers' traps were calculated: ΔE1 = 1.1 eV (for peak at 352 K) and ΔE2 = 1.3 eV (for peak at 388 K). [ABSTRACT FROM AUTHOR]

We report on the synthesis of CoWO4 nanoparticles by co-precipitation technique. The X-ray diffraction analysis confirmed the formation of phase pure wolframite type CoWO4. The characteristic vibrational information of CoWO4 was obtained through FT-IR measurement. The annealing temperature induced increase in optical energy band gap (2.33- 2.67 eV) of CoWO4 nanoparticles was observed. The photoluminescence bands at 438 and 490 nm realized the radiative transition of [WO4]2- tetrahedral group. [ABSTRACT FROM AUTHOR]

In recent years, interest in charmonium spectroscopy has been renewed by the unexpected discovery of multiple states that seemingly do not fit a conventional C C ¯ assigment. The BESIII experiment located at the BEPCII e+e− collider is at the forefront of investigations into these so-called XYZ states. With roughly 12 fb−1 of e+e− annihilation data above s = 3.8 GeV , BESIII both has direct access to exotic states with JPC = 1−− (Y-states) and can study X- and Z-states through radiative or mesonic transitions. Within the presentation, recent contributions of the BESIII experiment to the ongoing studies of XYZ states were highlighted and an outlook into future perspectives with BESIII was given. [ABSTRACT FROM AUTHOR]

Transparent magnesium aluminate spinel (MgAl2O4) ceramics doped with Ce3+ and Tb3+ ions were fabricated by Spark Plasma Sintering (SPS) technique. Complex characterization of the optical and photoluminescent properties of the sintered ceramic was carried out. The redshift in the in-line transmittance spectrum for RE ions doped spinel ceramics is observed. The photoluminescence spectrum excited by nitrogen laser consists of broad emission band with a maximum at λem = 435 nm for the MAS:0.1Ce ceramics The possible nature of this luminescence can be due to radiative transitions in the cerium ions from 5d to 4f level. There are a series of emission bands in 400 – 700 nm spectral range for MAS:0.1Tb ceramics. In the “blue” spectral region the complex host centers such as F-type centers are recorded. The luminescence decay kinetics analysis for all ceramics samples is performed. The effect of cerium and terbium oxide on the optical, photoluminescent properties of MgAl2O4-based transparent ceramics is discussed. [ABSTRACT FROM AUTHOR]

The present work reports, structural and luminescence studies on Eu3+ ions doped telluroborate glasses for red laser applications. The local structure and vibronic spectral analysis were performed in order to correlate them with the local field environment of Eu3+ ions on the basis of Raman and Phonon sideband spectroscopy. The Nephelauxetic intensity ratios (β) and bonding parameter (δ) values obtained from the absorption bands reveal the covalent nature of the Eu–O bond. The increasing Ω2 intensity parameters and R values confirms the higher asymmetry around Eu3+ ions and the covalency of Eu–O. The Judd-Ofelt (JO) intensity parameters were used to estimate the radiative properties such as transition probability (A), stimulated emission cross-section(σEP) branching ratio values (β) and radiative lifetimes (τR) for the observed emission transitions. [ABSTRACT FROM AUTHOR]

In the present work, Eu3+ ions doped boro-phosphate glasses (xEuBKP) were successfully prepared by melt quenching technique and their luminescence properties were investigated through recording optical absorption and photoluminescence spectral measurements. From the absorption spectral data, the optical band gap energy (Eopt) corresponding to the direct and indirect allowed transitions of the title glasses has been determined. The Judd-Ofelt (JO) intensity parameters Ωλ (λ=2, 4 and 6) were calculated from the emission spectra to analyse the symmetry of the ligand environment around Eu3+ ions and to examine the nature of the bond between Eu3+ ions and ligand oxygen in the prepared glasses. From the JO intensity parameters, radiative properties such as transition probability (A), stimulated emission cross section (σEP) radiative life time (τcal) and branching ratios (βR) of the studied glasses were determined and the suitability of the present Eu3+ doped boro-phosphate glasses for optoelectronic applications were discussed based on the obtained results. [ABSTRACT FROM AUTHOR]

The Dy3+-doped fluoroborate glasses with the composition (40-x)B2O3+20ZnO+20MgCO3+20NaF+xDy2O3 (where x = 0.1, 0.3 and 1.0) have been prepared by conventional melt quenching technique. The bonding parameter and oscillator strength for the prepared glasses have been calculated using the optical absorption spectra. Judd–Ofelt (JO) intensity parameters (Ωλ, λ = 2,4,6) have also been evaluated using optical absorption spectra. The radiative properties such as radiative transition probabilities (A), stimulated emission cross-section (σpE), lifetime (τR) and branching ratios (βR) have been calculated from luminescence spectra corresponding to 4F9/2→6H13/2 and 6H15/2 of excited levels of Dy3+ion. The CIE chromaticity color coordinates were evaluated from the emission spectra for all the glasses and found that they fall in the white light region. The dependence of spectral characteristic of Dy3+ ions due to concentration changes have been investigated and reported. The study concludes that the Dy3+ doped fluoroborate glasses are attractive material for white light applications. [ABSTRACT FROM AUTHOR]

Spectra of photoluminescence (PL) and X-ray excited luminescence (XRL) in region of 350 - 850 nm, PL excitation spectra in UV-VUV region (112 - 400 nm), thermally stimulated luminescence and absorption spectra were studied in SrF2 crystals doped with Er3+ ions. Intra-configurational radiative f-f transitions were studied at room temperature, 90 and 8 K under excitation with energy Eexc: a) in fundamental absorption region (Eexc ≥ Eg); b) in intracenter excitation region (Eexc < Eg); c) in infrared region (Eexc << Eg) with using laser 980 nm diode as exciting photons (up-conversion processes). The probability of radiative transitions from excited states of the impurity Er3+ center depends on energy of exciting photons. Up-conversion luminescence was studied in temperature interval from 90 to 460 K. While changing the temperature, intensity of main transitions (4S3/2 → 4I15/2, 4F9/2 → 4I15/2) changes. At high temperature (T > 387 K) a new low-energy transition 4I9/2 → 4I15/2 was detected. The presented results can be used as reference for spectroscopy of f-f radiation transitions in Er3+ ion in wide spectral range of exciting photons in crystals with fluorite-type structure. [ABSTRACT FROM AUTHOR]

Spectra of photoluminescence (PL) and X-ray excited luminescence (XRL) in region of 1.5-5.0 eV, PL excitationspectra (2.8-5.8 eV), PL decay kinetics were measured in Gd2O3 crystals doped both with Er3+ and Zn²⁺ ions. Synchrotron radiation (VEPP-3 storage ring, Novosibirsk, Russia) were used for XRL measurements. PL spectra were studied at room temperature and T= 88 K under excitation with energy Eexc: a) in fundamental absorption region (Eexc⩾Eg); b) in intracenter excitation region (Eexc

This study presents a summary of experimental data of K-shell fluorescence yields (ωK) published in the period of time between 2010 to february-2017. The fluorescence yields (ωK) of elements in the range 23≤Z≤60 taken directly from different sources were reviewed and presented in a table form. Finally, the experimental and empirical values in the literature have been reported and commented. [ABSTRACT FROM AUTHOR]

ZnO nanomaterial with praseodymium ions was prepared by chemical synthesis method. The ZnO nanomaterial was characterized by XRD, SEM and TEM. Their absorption in UV-VIS/NIR regions was measured at room temperature. The experimental oscillator strengths were calculated from the areas under the absorption bands. Eight absorption bands have been observed. From these spectral data various energy interaction parameters like Slater-Condon, Lande, Racah, Nephelauxetic ratio and bonding parameters have been computed. Judd-Ofelt analysis has been carried out using the absorption spectra to evaluate the radiative properties for luminescent levels of the praseodymium ion and discussed.The observed nano particle size is 2nm. [ABSTRACT FROM AUTHOR]

We present preliminary results of the evaluation of the next-to-leading-order (NLO) relativistic corrections to the heavy quarkonium electric dipole transition (E1) rate. In our evaluation we use the quark-antiquark potential up to 1/m2 corrections that includes the effective string theory expression for the long range, a review on the method to construct this potential is given. Our results compare favorable with the experiments and may provide predictions for the rates for which no experimental data is yet available. [ABSTRACT FROM AUTHOR]

We present preliminary results of the evaluation of the next-to-leading-order (NLO) relativistic corrections to the heavy quarkonium electric dipole transition (E1) rate. In our evaluation we use the quark-antiquark potential up to 1/m2 corrections that includes the effective string theory expression for the long range, a review on the method to construct this potential is given. Our results compare favorable with the experiments and may provide predictions for the rates for which no experimental data is yet available. [ABSTRACT FROM AUTHOR]

Cr-doped GdAlO3 (Cr:GdAlO3) is shown to produce remarkably high-intensity spin-allowed broadband luminescence with sufficiently long decay times to make effective luminescence-decay-time-based temperature measurements above 1000 °C. This phosphor is therefore an attractive alternative to the much lower luminescence intensity rare-earth-doped thermographic phosphors that are typically utilized at these elevated temperatures. In particular, Cr:GdAlO3 will be preferred over rare-earth-doped phosphors, such as Dy:YAG, at temperatures up to 1200 °C for intensity-starved situations when the much lower emission intensity from rare-earth-doped phosphors is insufficient for accurate temperature measurements in the presence of significant radiation background. While transition-metal-doped phosphors such as Cr:Al2O3 (ruby) are known to exhibit high luminescence intensity at low dopant concentrations, quenching due to nonradiative decay pathways competing with the 2E to 4A2 radiative transition (R line) has typically restricted their use for temperature sensing to below 600 °C. Thermal quenching of the broadband 4T2 to 4A2 radiative transition from Cr:GdAlO3, however, is delayed until much higher temperatures (above 1000 °C). This spin-allowed broadband emission persists to high temperatures because the lower-lying 2E energy level acts as a reservoir to thermally populate the higher shorter-lived 4T2 energy level and because the activation energy for nonradiative crossover relaxation from the 4T2 level to the 4A2 ground state is high. The strong crystal field associated with the tight bonding of the AlO6 octahedra in the GdAlO3 perovskite structure is responsible for this behavior. [ABSTRACT FROM AUTHOR]

A new technique to measure (p,n) charge-exchange reactions in inverse kinematics at intermediate energies on unstable isotopes was successfully developed and used to study the 56Ni(p,n) reaction at 110 MeV/u. Gamow-Teller transition strengths from 56Ni to 56Cu were obtained and compared with shell-model predictions in the pf-shell using the KB3G and GXPF1A interactions. The calculations with the GXPF1A interaction reproduce the experimental GT strength distribution much better than the calculations that employed the KB3G interaction, indicating deficiencies in the spin-orbit and proton-neutron residual potentials for the latter. The results are important for improving the description of electron-capture rates on nuclei in the iron region, which are important for modeling the late evolution of core-collapse and thermonuclear supernovae. [ABSTRACT FROM AUTHOR]

We discuss the possibility to probe the QCD critical point during the prompt black hole formation. In black hole formation processes, temperature and baryon chemical potential become as high as T ∼ 90MeV and μB ∼ 1300MeV. This high baryon chemical potential would allow nuclear matter to experience the QCD phase transition, and the temperature may be higher than the QCD critical point temperature. We compare the phase boundary in chiral effective models and the thermal environment obtained in the ν radiation hydrodynamical calculation of the gravitational collapse of a 40M⊙ star leading to the black hole formation. This comparison suggests that quark matter is likely to be formed, and the QCD critical point may be swept. [ABSTRACT FROM AUTHOR]

The decay B→γℓνℓ receives a numerically large soft-overlap contribution which is formally next-to-leading order in the expansion in the inverse photon energy, 1/Eγ. We point out that this contribution can be calculated with little model-dependence making use of dispersion relations and duality, in full analogy with the similar contribution to the γγ*→π transition form factor. This result strengthens the case for the utility of the B→γℓνℓ decay for constraining the B-meson distribution amplitude and determining its most important parameter, the inverse moment λB. [ABSTRACT FROM AUTHOR]

We scrutinize recent findings on the charged-pion elastic form factor and the form factors entering in neutral-meson-to-photons transition amplitudes within the framework of QCD sum rules. [ABSTRACT FROM AUTHOR]

Taking into account the two-gluon condensate contributions, the transition form factors enrolled to the low energy effective Hamiltonian describing the semileptonic [formula] decay channel are calculated within three-point QCD sum rules. [ABSTRACT FROM AUTHOR]

We present the results of our recent analysis of the meson-photon transition form factors FPγ(Q2) for the pseudoscalar mesons P = π0,η,η′,ηc, using the local-duality version of QCD sum rules. [ABSTRACT FROM AUTHOR]

B→K*μ+μ- angular observables have become a key ingredient in global model-independent analyses of b → s transitions. However, as experimental precision improves, the use of theoretically clean quantities becomes a crucial issue. Global analyses that use clean observables integrated in small bins are already a reality, opening up a new chapter in our quest for New Physics. [ABSTRACT FROM AUTHOR]

Form factors are important non-perturbative properties of hadrons. They give information about the internal structure of the hadrons. In this work, iso-vector axial-vector and iso-vector tensor form factors of the nucleon and the iso-vector axial-vector Δ → N transition form factor calculations in QCD Sum Rules are presented. [ABSTRACT FROM AUTHOR]

In the presence of a chemical potential, the effect of a magnetic field on chiral symmetry breaking goes beyond the well-known magnetic catalysis. Due to a subtle interplay with the chemical potential, themagnetic field maywork not only in favor but also against the chirally broken phase. At sufficiently large coupling, themagnetic field favors the broken phase only for field strengths beyond any conceivable value in nature. Therefore, in the interior of magnetars, a possible transition from chirally broken hadronic matter to chirally symmetric quark matter might occur at smaller densities than previously thought. [ABSTRACT FROM AUTHOR]

We extract constraints on the pion distribution amplitude from available data on the pionphoton transition form factor in the framework of light-cone sum rules. A pronounced discrepancy (2.7 - 3)σ between the Gegenbauer expansion coefficients extracted from the CELLO, CLEO, and Belle experimental data relative to those from BaBar is found. Predictions for the pion-photon transition form factor are presented by employing a pion distribution amplitude obtained long ago from QCD sum rules with nonlocal condensates. These predictions comply with the Belle data but disagree with those of BaBar beyond 9 GeV2. [ABSTRACT FROM AUTHOR]

The recent BaBar measurements of the γγ*→π0 transition form factor show spectacular deviation from perturbative QCD prediction for large space-like Q2 up to 34GeV2. In this talk, I would like to discuss a recent work on the chiral anomaly effects in the γγ*→π0 transition form factor F(Q2) at large momentum squared Q2. Using PCAC and the Adler-Bell-Jackiw chiral anomaly triangle graph, we find that, F(Q2) at large Q2 behaves as (m2Q2)×(ln(Q2/m2))2 and is in striking agreement with the BaBar data with m = 135MeV which also reproduces very well the CLEO data at lower Q2. The new Belle measurements could also be fitted with m = 120MeV. [ABSTRACT FROM AUTHOR]

A study of the shape transition from spherical to axially deformed nuclei in the even Ce isotopes using the nucleon-pair approximation of the shell model is reported. As long as the structure of the dominant collective pairs is determined using a microscopic framework appropriate to deformed nuclei, the model is able to produce a shape transition. The resulting transition is too rapid, however, with nuclei that should be transitional being fairly well deformed. The possibility of using several pairs with each angular momentum to improve the description of the transitional region is discussed. [ABSTRACT FROM AUTHOR]

The interacting boson model (IBM) of Arima and Iachello is applied to calculate nuclear charge radii and electric monopole transitions of even-even nuclei in the rare-earth region. Consistent operators are used for the two observables. In addition, a relation between summed M1 strength and ρ(E0) values is pointed out. [ABSTRACT FROM AUTHOR]

The mean-field approximation predicts pairing and shape phase transitions in nuclei as a function of temperature or excitation energy. However, in the finite nucleus the singularities of these phase transitions are smoothed out by quantal and thermal fluctuations. An interesting question is whether signatures of these transitions survive despite the large fluctuations. The shell model Monte Carlo (SMMC) approach enables us to calculate the statistical properties of nuclei beyond the meanfield approximation in model spaces that are many orders of magnitude larger than spaces that can be treated by conventional diagonalization methods. We have extended the SMMC method to heavy nuclei and used it to study the transition from vibrational (spherical) to rotational (deformed) nuclei in families of rare-earth isotopes. We have calculated collective enhancement factors of level densities as a function of excitation energy and found that the decay of the vibrational and rotational enhancements is well correlated with the pairing and shape phase transitions, respectively. [ABSTRACT FROM AUTHOR]

Large scale shell model calculations based on a new diagonalization algorithm are performed in order to investigate the mixed symmetry states in chains of nuclei in the proximity of N=82. The resulting spectra and transitions are in agreement with the experiments and consistent with the scheme provided by the interacting boson model. [ABSTRACT FROM AUTHOR]

By using type Ia supernovae (SN Ia) data in combination with recent baryonic acoustic oscillations (BAO) and cosmic microwave background (CMB) observations we constrain a kink-like parametrization of the deceleration parameter (q). By adopting a likelihood approach to deal with the SN Ia data we constrain the model parameters and show that, in combination with BAO/CMB, SN Ia data processed with the MLCS2k2 fitter favors Dvali-Gabadadze-Porrati-like cosmological models, while SALT2 fitter favors ΛCDM-like ones. [ABSTRACT FROM AUTHOR]

In this contribution, I will review the most recent developments that concern the transition from a primordial, predominantly massive mode of star formation - the Population III stars - to a mode of star formation characterized by the first low mass and long lived stars - the Population II stars. Although the recent observation of a star in the Galactic Halo with a total metallicity of only Z = 4.5×10-5Z⊙ has demonstrated that stars with masses of approximately ∼ 0.8M⊙ can form even at these extremely low metallicities, there are many aspects of the Pop III/II transition that are still poorly understood and that certainly require further investigation. For this reason, I have organized my contribution into three fundamental questions which I try to address based on the current theoretical and observational indications. [ABSTRACT FROM AUTHOR]

We investigate how radiative feedback from the first stars affects the assembly of the first dwarf galaxies. We perform cosmological zoomed smoothed particle hydrodynamics simulations of a galaxy assembling inside a halo reaching a virial mass ∼ 109 M⊙ at z = 10. The simulations follow the non-equilibrium chemistry and cooling of primordial gas and the subsequent conversion of the cool dense gas into massive metal-free stars. To quantify the radiative feedback, we compare a simulation in which stars emit both molecular hydrogen dissociating and hydrogen ionizing radiation with a simulation in which stars do not emit radiation but remain dark. Photodissociation and photoionization exert a strong negative feedback on the assembly of the galaxy inside the minihalo progenitor, impeding gas condensation and suppressing star formation. The radiative feedback on the gas implies a suppression of the central dark matter densities in the minihalo by factors of up to a few, which is a significant deviation from the singular isothermal density profile characterizing the dark matter distribution in the absence of radiative feedback. The properties of the galaxy become insensitive to the inclusion of radiation once the minihalo turns into an atomic cooler. The formation of a rotationally supported extended disk inside the atomically cooling galaxy therefore is a robust outcome of our simulations. Our simulations make predictions for observations with the upcoming James Webb Space Telescope. [ABSTRACT FROM AUTHOR]

In this contribution, we review our efforts toward understanding the typical mass-scale of primordial stars. Our direct numerical simulations show that, in both of Population III.1 and III.2 cases, strong UV stellar radiative feedback terminatesmass accretion onto a protostar. An HII region formed around the protostar expands very dynamically into the accreting envelope, and cuts off the gas supply to a circumstellar disk. The disk is exposed to the stellar UV radiation and loses its mass by photoevaporation. The derived final masses are 43 M⊙ and 17 M⊙ in our fiducial Population III.1 and III.2 cases. Much more massive stars, however, should form in other exceptional conditions. In atomic-cooling halos where H2 molecules are dissociated, for instance, a protostar grows via very rapid mass accretion with the rates M*∼0.1-1M⊙yr-1. Our new stellar evolution calculations show that the protostar significantly inflates and never contracts to reach the zero-agemain-sequence stage in this case. Such "supergiant protostars" have very low UV luminosity, which results in weak radiative feedback against the accretion flow. In the early universe, supermassive stars formed through this process might provide massive seeds of supermassive black holes. [ABSTRACT FROM AUTHOR]

While the exact masses of the first stars are still unknown, it remains relatively well accepted that the Pop III initial mass function is not identical to that of stars forming today. This transition in star forming modes is due to the introduction of metals produced in the first supernovae. These metals enhance the radiative cooling efficiency of gas through fine-structure lines, molecular transitions, and thermal emission from dust grains. Simulations have made great contributions to our understanding of the ability of metals to induce fragmentation in collapsing gas, but little attention has been paid the actual conditions present when the Universe becomes enriched with metals for the first time. We present the results from a simulation of the formation of the first metal-enriched stars under realistic conditions. We simulate a Population III star forming halo and assume the formation of a 40 M⊙ metal-free star. Using 3D radiation hydrodynamics, we then compute the evolution of the HII region and the blast-wave of the subsequent core-collapse supernova. We then follow the simulation until the first metal-enriched prestellar clouds collapse. We report on the status of this ongoing simulation. [ABSTRACT FROM AUTHOR]

We analyze the big bounce transition of the quantum FRW model in the setting of the nonstandard loop quantum cosmology (LQC). Elementary observables are used to quantize compound observables. The spectrum of the energy density operator is bounded and continuous. The spectrum of the volume operator is bounded from below and discrete. It has equally distant levels defining a quantum of the volume. The discreteness may imply a foamy structure of spacetime at semiclassical level which may be detected in astro-cosmo observations. The nonstandard LQC method has a free parameter that should be fixed in some way to specify the big bounce transition. [ABSTRACT FROM AUTHOR]

Spontaneous coherence and Kosterlitz-Thouless transition to superfluid state of exciton polaritons in the system of coupled quantum wells embedded in microcavity was considered at low temperatures. Contrary to the infinite two-dimensional system without confinement, the Bose-Einstein condensation of exciton polaritons in the system of coupled quantum dots embedded in optical microcavity can take place. Growth of confining potential steepness fleads to the increase of the critical temperature. Magnetic field influence on the critical temperature can be non-monotonous for certain region of control parameters because of the competition of two mechanisms: (i) growth of the effective mass of magnetoexciton which leads to decreasing of critical temperature; and (ii) growth of effective parameter of confinement, which increases the critical temperature and favors condensate formation. [ABSTRACT FROM AUTHOR]

The Russian fission community places several heavy demands to quality of fusion neutron source for the first step of investigation of minority transmutations ("burning") and breading of nuclear fuel. They are: the steady state regime of neutron production (not rare 80% of main operation time), the total power on neutron flux should be not lower than 20MW with surface neutron load not lower than 0.2MW/m2. Between the current fusion devices: mirror traps, reverse field pinches, stellarators, spherical torus and tokamaks only lasts have today the some probability to fulfill in the near future these hard demands. Two well known DT-tokamaks with neutron power production higher 10MW - TFTR and JET-had maximal neutron load approximately 0.1MW/m2 only in transient (with time scale lower 1s) regimes. The quasi steady state neutron emission regime (∼5MW, 5sec) was performed in JET with mean surface neutron load lower than 0.025MW/m2 only. In this communication it will be discussed the main needs of JET scale tokamak improvement for increase on neutron load up to 0.2MW/m2. They are: decrease of Zeff by ECRH and lithium use as plasma facing components, the increase of energy of steady state neutral injectors up to 150-170keV (tritium), the He removal and creation of closed loop of DT fuel circulation. [ABSTRACT FROM AUTHOR]

We summarize recent theoretical developments in the field of radiative and semileptonic penguin decays. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions can be studied in both β decay and charge exchange (CE) reactions. If isospin is a good quantum number, then the Tz = -1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the TZ = -1 fp-shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (33He, t) measurements on the mirror TZ = +1 target nuclei studied in high resolution at RCNP, Osaka. The β decay experiments were performed as part of the STOPPED beam RISING campaign at GSI. [ABSTRACT FROM AUTHOR]

Nd3+ doped oxide glasses of the type xNa2O-30 PbO-(69.5-x) B2O3-0.5Nd2O3 were prepared and investigated for physical and spectroscopic properties. Optical absorption spectra and Judd-Ofelt theory has been used to determine the oscillator strengths and the intensity parameters Ωλ (λ=2, 4, 6). The radiative transition probability (A), radiative lifetime (τR) and branching ratio (βR) for the fluorescent levels of Nd3+ in the prepared glasses have been determined. The lasing efficiency of the prepared glasses has been characterized by the spectroscopic quality factor (Ω4/Ω6), the value of which is in the range 0.2-1.5, typical for Nd3+ in different laser hosts. The radiative transition probability of the potential lasing transition 4F3/2 → 4I11/2 of Nd3+ ions is found to increase with increase in content of Na2O. [ABSTRACT FROM AUTHOR]

Toroidal plasma current is started and ramped up by injecting microwave power in the electron cyclotron range of frequency without induction in the LATE device. Radial scanning with hard X-ray pulse height analysis reveals the production of high energy electrons with average energy ∼100 keV in the radial region from R = 28 cm to 40.5 cm, which are heated by electron Bernstein wave. The radial profile of photon counts in the energy range from 25 to 200 keV is very similar to that of perpendicular pressure obtained by magnetic measurement and equilibrium analysis, suggesting that a significant portion of trapped electrons exists outside the last closed flux surface. The plasma current inside the LCFS is carried mainly by passing electrons, while some portion of the outside current may be generated as a result of the toroidal precession of trapped electrons. [ABSTRACT FROM AUTHOR]

Improving the up-conversion efficiency is the key issue in tellurite glasses. The quantum efficiency, radiative transition rate and lifetimes of excited states are greatly influenced by the optical properties of the host material, ligand field, multiphonon relaxation processes, impurities, temperature and concentration of erbium ions. We develop a comprehensive 4-level model to examine the radiative and nonradiative (NR) decay processes for the green (4S3/2→4I15/2) and red (4F9/2→4I15/2) emission over a temperature range of (10-340 K) and concentration range of (0.1-4.5 mol.%). Concentration dependent enhancement and thermal quenching of efficiency for up-conversion is investigated using the derived rate equations. These features are attributed to the NR energy transfer processes, trapped impurity effects, and thermal assisted hopping. The unusual nature of temperature and concentration dependent quenching effects for green and red emission is queries for further investigations. It is further suggested that to achieve higher infrared to visible up-converted efficiency in tellurite glasses the NR channels for energy and charge transfer by phonon and impurity mediated process has to be minimized. Our results on pump power dependent emission intensity, quantum efficiency, luminescence intensity, radiative lifetimes, and transition probabilities are in conformity with other experimental findings. [ABSTRACT FROM AUTHOR]

A brief report of some recent experimental developments concerning the X, Y and Z charmoniumlike mesons states and other puzzling states from the BaBar, Belle, BESIII and CDF experiments is presented. [ABSTRACT FROM AUTHOR]

In this paper we report on an experimental and theoretical study of quasimolecular absorption of Xe-He and Kr-He collision pairs near the Xe (5p6 1S0-5p56s 1,3P1) and Kr (4p6 1S0-4p55s 1,3P1) resonance transitions. [ABSTRACT FROM AUTHOR]

Spectral profiles and lifetimes have been calculated for the He(21S)-Ne loosely bound molecule. It has been found that the radiating properties of the molecule depend strong on temperature. [ABSTRACT FROM AUTHOR]

The first stars in the universe were typically very massive, but those near us are not. The metallicity in the star-forming gas is thought to have played a key role in this transition of characteristic stellar mass scale. By studying the evolution of low-metallicity star-forming clouds up to the formation of protostars by way of radiation hydrodynamics with spherical symmetry, we discuss their fragmentation mass scales. The critical metallicity for low-mass fragmentation is in the range of Zcr = 10-6-10-5Z⊙. Although the exact value is still unknown due to uncertain dust nature in the early universe, the small value of Zcr means that low-mass star formation begun just after the first episode of metal enrichment. We also evaluate the upper limit on the stellar mass by the stellar feedback. Owing to the higher density in the envelope and thus higher protostellar accretion rate, the upper limit of stellar mass increases toward lower matallicity. [ABSTRACT FROM AUTHOR]

We review recent progress in calculating radiative transition form factors using lattice QCD. We discuss results in the charmonium region involving excited states, states of high spin and exotics. As well as highlighting interesting results involving an exotic 1-+ states and a vector-hybrid candidate, we give comparison with experimental data and models. Some lattice calculations of baryon photocouplings are also mentioned. We conclude with some comments on future prospects. [ABSTRACT FROM AUTHOR]

In this paper, a circuit model is devised to analyze nonlinear behaviour of quantum cascade lasers. Such nonlinear behavior influences the light output when the laser is driven by currents comparable to the average (DC) current. The simplified 2-level rate equations are first improved. Next, the circuit model is obtained following the approach for interband lasers. The difference between the circuit models of quantum cascade lasers and interband lasers is pointed out. The circuit model is simpler compared to that obtained from a 3-level model. Unlike a circuit model derived earlier from the 2-level model, the present model can handle both small and large current drives. [ABSTRACT FROM AUTHOR]

Radiative and electroweak penguin decays of B mesons are a sensitive probe of new physics beyond the Standard Model. We study the inclusive and exclusive radiative and electroweak penguin decays of B meson and also search an exotic particle seen by the HyperCP experiment. The measurements are based on a large data sample of 605 fb-1 containing 657 millions BB pairs collected at the Υ(4S) with the Belle detector at the KEKB energy asymmetric e+e- collider. [ABSTRACT FROM AUTHOR]