Magnetic Dipole Transition Probabilities Research Articles

Altering of the Electric and Magnetic Dipole Transition Probability of Eu3+ in YPO4 Lattice by Codoping of K+ Ion: Potential Materials for Imaging and Heating

Altering of the Electric and Magnetic Dipole Transition Probability of Eu³⁺ in YPO₄ Lattice by Codoping of K⁺ Ion: Potential Materials for Imaging and Heating

Systematic Projected Shell Model Study of Even-Even Dysprosium Isotopes

Back-bending phenomenon is one of the important phenomena usually seen at high spin states of even - even heavy nuclei. As a result, any changes in the behavior of nuclear rotation, such as increase in moment of inertia versus rotational frequency can be shown in the usual back-bending plots which have been studied in many papers before. In this paper we show for the first time that these changes can be seen in the ratio of electromagnetic reduced transition probabilities B (E2) and B (M1) in even - even 152-164 Dy isotopes using the Projected Shell Model (PSM) theory. The electric quadrupole transition probability B (E2) and the magnetic dipole transition probability B (M1) moments are sensitive to nuclear shape deformation and nuclear charge distribution, respectively. Our findings confirm the well-known back-bending previously seen and are in good agreement with experimental results. While intrinsic quadrupole moments are constant for each Dy isotope, the new findings show that spectroscopic quadrupole moments are increasing with spin. 15.00 Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

Characterization of oxyfluoride glasses doped with rare-earth ions through structural, thermal, and optical application thereof

Novel transparent glasses and glass-ceramics were fabricated by using melt-quenching technique with the following composition: TeO2–WO3–Nb2O5–KF–La2O3 doped with Tm2O3. Different properties and physical parameters of these glasses were investigated. As the concentration of Tm3+ ions increases, the linear refractive index increases while the optical energy gap decreases. With high Tm3+ ion concentration creates nucleation in the glass matrix this was investigated by x-ray diffraction. The Judd-Ofelt parameters used to calculate the electric and magnetic dipole transition probabilities, branching ratios, and radiative lifetimes of various excited states of Tm3+-doped parent glass. The emission cross section values for the 3F4→3H6 transition computed by using the McCumber hypothesis. The stimulated emission cross section σeFL(λ) and gain values of fabricated glass increase with Tm3+ ions. The spectroscopic quality and figure of merit (FOM) gain (σeFL(λ)×τR) factors were evaluated for the prepared transparent glass. Furthermore, the produced glasses were demonstrated to have low OH content and they have high fluoride ion content. These important properties of the glasses and glass-ceramics make them suitable for use in photonic applications.

Theoretical Study of Isospin Mixing States with T> 0 in sd Even-Even N=Z Nuclei Using Shell Model

Nuclear excited states with T > 0 in sd even-even N=Z nuclei have been studied by using shell model. The calculations have employed the USDB Hamiltonian in order to predict the energy levels, the reduced electric quadrupole transition probabilities and reduced magnetic dipole transition probabilities. The study also include the average number of nucleons in each sd- active orbitals. The results compared with available experimental data. The comparison showed a good agreement between theoretical and experimental energy sates for most of the states studied in this work. On the other hand there was a difference between theoretical and experimental values of transition probabilities, but it can be said that it remained within the acceptable range of the difference.

Nuclear structure features in 72-80Se isotopes

Interacting boson model (IBM – 1 and IBM – 2) have been used to perform a whole studying for isotopes. The low lying positive party states, dynamic symmetries, mixed symmetry states MSS, reducing electric quadruple transition probabilities B(E2), branching ratio, quadruple momentum , reducing magnetic dipole transition probability B(M1), mixing ratio δ(E2/M1), reducing electric monopole transition probability B(E0), and X(E0/E2) ratio have been investigated. U(5) features are the dominant in with addition of a 2 small effect of parameter started from to isotopes, energy ratios show that isotopes as the nearest isotopes to typical vibrational limit while isotopes tend towards the rotational region that lied on U(5) - SU(3), leg of “Casten’s triangle”. Spin and party for many energy levels and electromagnetic transition probability are confirmed. The mixing symmetry states in isotopes are slowly increased with ζ2 while there is no clear effected in isotope. The calculated branching ratios B(E2), B(M1) mixing ratios δ(E2/M1), B(E0), and X(E0/E2) depend in comparisons with fewer available experimental data. The results are in acceptable agreement; to completed a perfect comparison, more experimental investigations are still needed to these nuclei. isotopes have small values of electric quadruple moment of state.

Investigation of Mixed Symmetry States in 170-178Yb isotopes

low-lying positive parity states, dynamic symmetries, mixed symmetry states (MSS), reducing electric quadrupole transition probabilities B(E2), branching ratio, reducing magnetic dipole transition probabilities B(M1), and mixing ratios δ(E2/M1) for 170-178Yb have been investigated by applied IBM-1 and IBM-2 program package. The software package IBM-1 and IBMT computer code for IBM-1 and Neutron Proton Boson NPBOS and Neutron Proton Boson Electromagnetic NPBEM software package have been used. The Ytterbium nuclei with the (170 − 178) mass number considered as rotational nuclei after applying the first and second interacting boson model with studying dynamic symmetry and energy ratios , and that approximated to (3.33,7 and 12). The reducing transition probability for electric quadruple B(E2) and branching ratios that state the small values of the ratios R′ and R″ as having rotational characteristics. A study of the mixed symmetry state of these nuclei shows that the lower energy mixing level is the first 1+ level, which distinguishes the rotational determination nuclei. The energy levels values for the states have a clear mixed symmetry state (MSS) directly proportional with Majorana parameters ζ2, while , and , tend to be approximately more conservative.

Influence of BaX2 (X = Cl, F) and Er2O3 concentration on the physical and optical properties of barium borate glasses

Er3+ ions doped oxyhalide barium borate glasses were prepared by means of conventional melt quenching technique. In the studied glass system, besides the Er3+ doping, barium oxide was partially replaced by BaF2 and/or BaCl2. The amorphous nature of as-prepared glasses was confirmed by X-ray diffraction patterns. The effects of the compositional changes were investigated through spectroscopic techniques such as optical absorption, emission and decay lifetime. It was found that the luminescence and decay lifetime of Er3+: 4I13/2 → 4I15/2 transition are affected by both Er3+ doping and halide insertions. By applying the Judd-Ofelt (JO) theory, the JO intensity parameters (Ωt, t = 2, 4, and 6) were calculated, and the trend Ω2 > Ω4 > Ω6 was found, which is in accordance with previous studies. Optical properties such as electric and magnetic dipole transition probabilities, fluorescence branching ratios, integrated emission cross sections and radiative lifetimes were also obtained and discussed for many excited states of Er3+ ions. The lifetime of the 4I13/2 excited level was measured and compared with the calculated one.

Theoretical investigation on forbidden transition properties of fine-structure splitting in 2D state for K-like ions with **Project supported by the National Natural Science Foundation of China (Grant Nos. 91436103, 91536102, and 91336211), the Research Programme of National University of Defense Technology, China (Grant No. JC15-0203), and the Strategic Priority Research Programme of the Chinese Academy of Sciences (Grant No. XDB21030300).

Excitation energies, magnetic dipole, and electric quadrupole transition probabilities of the transition in the potassium-like (K-like) sequence with are investigated by using the multi-configuration Dirac–Hartree–Fock (MCDHF) method. The contributions of the electron correlations, Breit interaction, and the leading-order quantum electrodynamic (QED) effects on the transition properties are analyzed. The present results are interested in the laboratory tokamak and the astronomical observations. Furthermore, the feasibility of these ions for the highly charged ion (HCI) clocks is discussed. Considering the wavelength of lasers and manipulation process of the atomic clocks, Cu10+ and Zn11+ are recommended as promising candidates with achievable quality factors at the 1015 level.

Reduced Transition Probabilities for the Gamma Decay of the 7.8eV Isomer in ^{229}Th.

The reduced magnetic dipole and electric quadrupole transition probabilities for the radiative decay of the ^{229}Th 7.8 eV isomer to the ground state are predicted within a detailed nuclear-structure model approach. We show that the presence and decay of this isomer can only be accounted for by the Coriolis mixing emerging from a remarkably fine interplay between the coherent quadrupole-octupole motion of the nuclear core and the single-nucleon motion within a reflection-asymmetric deformed potential. We find that the magnetic dipole transition probability which determines the radiative lifetime of the isomer is considerably smaller than presently estimated. The so-far disregarded electric quadrupole component may have non-negligible contributions to the internal conversion channel. These findings support new directions in the experimental search of the ^{229}Th transition frequency for the development of a future nuclear frequency standard.

Understanding the complexation of Eu3 + with potential ligands used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle: A luminescence investigation

A systematic photoluminescence based investigation was carried out to understand the complexation of Eu3+ with different ligands (TBP: tri-n-butyl phosphate, DHOA: di-n-hexyl octanamide, Cyanex 923: tri-n-alkyl phosphine oxide and Cyanex 272: Bis (2,4,4 trimethyl) pentyl phosphinic acid) used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle. In case of TBP and DHOA complexes, 3 ligand molecules coordinated in monodentate fashion and 3 nitrate ion in bidentate fashion to Eu3+ to satisfy the 9 coordination of Eu. In case of Cyanex 923 and Cyanex 272 complexes, 3 ligand molecules, 3 nitrate ion and 3 water molecules coordinated to Eu3+ in monodentate fashion. The Eu complexes of TBP and DHOA were found to have D3h local symmetry while that for Cyanex 923 and Cyanex 272 were C3h. Judd–Ofelt analysis of these systems revealed that the covalency of EuO bond followed the trend DHOA>TBP>Cyanex 272>Cyanex 923. Different photophysical properties like radiative and non-radiative life time, branching ratio for different transitions, magnetic and electric dipole moment transition probabilities and quantum efficiency were also evaluated and compared for these systems. The magnetic dipole transition probability was found to be almost independent of ligand field perturbation while electric dipole transition probability for 5D0-7F2 transition was found to be hypersensitive with ligand field with a trend DHOA>TBP>Cyanex 272>Cyanex 923.

Effect of phase modifiers TBP and iso-decanol on the extraction and complexation of Eu3+ with CMPO

ABSTRACTThe effect of tri-n-butyl phosphate (TBP) and iso-decanol as phase modifiers on the complexation of Eu3+ with octyl-phenyl N,N-diisobutyl carbamoyl methyl phosphine oxide (CMPO) was studied. On an increase of iso-decanol the extraction efficiency of Eu3+ decreases. The metal–ligand stoichiometry was found to be 1:3. The Eu complex of CMPO–TBP was more symmetric compared to CMPO–iso-decanol. The Eu3+ complex exhibited D3h and C3h symmetry for 30% and 5% iso-decanol, while that for TBP was C6v. The radiative, non-radiative life time, electric and magnetic dipole transition probabilities, branching ratio, quantum efficiency etc. were evaluated. The covalency between Eu3+ and CMPO is as follows: CMPO–TBP < CMPO-5% iso-decanol < CMPO-30% iso-decanol.

Radiative rates for forbidden M1 and E2 transitions of astrophysical interest in doubly ionized iron-peak elements

Aims. Accurate and reliable atomic data for lowly ionized Fe-peak species (Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) are of paramount importance for analyzing the high-resolution astrophysical spectra currently available. The third spectra of several iron group elements have been observed in different galactic sources, such as Herbig-Haro objects in the Orion Nebula and stars like Eta Carinae. However, forbidden M1 and E2 transitions between low-lying metastable levels of doubly charged iron-peak ions have been investigated very little so far, and radiative rates for those lines remain sparse or nonexistent. We attempt to fill that gap and provide transition probabilities for the most important forbidden lines of all doubly ionized iron-peak elements. Methods. We carried out a systematic study of the electronic structure of doubly ionized Fe-peak species. The magnetic dipole (M1) and electric quadrupole (E2) transition probabilities were computed using the pseudo-relativistic Hartree-Fock (HFR) code of Cowan and the central Thomas-Fermi-Dirac-Amaldi potential approximation implemented in AUTOSTRUCTURE. This multiplatform approach allowed for consistency checks and intercomparison and has proven very useful in many previous works for estimating the uncertainties affecting the radiative data. Results. We present transition probabilities for the M1 and E2 forbidden lines depopulating the metastable even levels belonging to the 3dk and 3dk−14s configurations in Sc III (k = 1), Ti III (k = 2), V III (k = 3), Cr III (k = 4), Mn III (k = 5), Fe III (k = 6), Co III (k = 7), and Ni III (k = 8).

A systematic and detailed investigation of radiative rates for forbidden transitions of astrophysical interest in doubly ionized iron peak elements

AbstractWe carried out a systematic study of the electronic structure of doubly-ionized Fe-peak species, from Sc III to Ni III. The magnetic dipole (M1) and electric quadrupole (E2) transition probabilities were computed using the pseudo-relativistic Hartree-Fock (HFR) method and the central Thomas-Fermi-Dirac-Amaldi potential approximation implemented in the AUTOSTRUCTURE code. This multi-platform approach allowed for consistency checks and intercomparison and has proven very useful in many previous works for estimating the uncertainties affecting the radiative data.

Probing of the local environment and calculation of J.O. parameters for Eu3+ CMPO functionalized pillararene complexes by time resolved fluorescence spectroscopy

An attempt was made to understand the complexation of Eu3+ with structurally modified CMPO-functionalized pillararenes by luminescence spectroscopy. Formation of single species with different numbers of inner sphere water molecules was found to be present for all the complexes. On increasing spacer length between ligating moieties and supramolecular pillararenes, the stereo-chemical crowding around ligating oxygen decreased. Therefore, strong covalent metal–oxygen bond was formed which was reflected in the increasing trend of the computed Ω2 values (Judd–Offelt parameter): LI (4.66×10−20)<LII (6.82×10−20)<LIII (7.85×10−20). Deconvolution of each 5D0→7F1, 5D0→7F2 and 5D0→7F4 transitions into two peaks revealed that the most probable local symmetry around Eu3+ was C6/C6v. The radiative lifetime for the Eu complexes followed LI (4.09ms)>LII (3.19ms)>LIII (2.94ms) while the branching ratio values for all three complexes followed the same trend as β2>β4>β1. The other photo-physical constants like asymmetric factor, quantum efficiency, magnetic and electric dipole transition probabilities were also computed.

Judd–Ofelt analysis of Ho3+ doped in ceramic CaSc2O4

A Judd–Ofelt analysis was performed on a calcium scandate (CaSc2O4) ceramic sample doped with 2at% Ho3+. Using the measured lifetime of 5I7 level to calibrate the absorption spectrum, the Judd–Ofelt parameters were obtained: Ω2 = 3.78×10−20cm2, Ω4 = 5.17×10−20cm2, and Ω6 = 1.92×10−20cm2. The electric-dipole and magnetic-dipole transition probabilities, radiative lifetimes and luminescence branching ratios were calculated. The quantum efficiency of the green emitting levels (5F4, 5S2) was found: 54%. The calibration method also allowed the estimation of the ‘effective’ thickness of the ceramic sample: approximately eight times greater than the geometric thickness.

Characterization of Tm3+ doped TNZL glass laser material

In this paper, a new tellurite glass (85TeO2·5.0Nb2O5·5.0ZnO·5.0LiF) doped with 1mol% Tm2O3 was prepared by melt-quenching technique. Differential scanning calorimetry (DSC) measurements indicate a good thermal stability, X-ray diffraction patterns show no sign of crystallization. Precise refractive index measurements were performed on five different wavelengths by a prism spectrometer. The optical energy gap, the Sellmeier energy gap and the dispersion energy were estimated. Judd–Ofelt intensity parameters were evaluated in order to obtain electric and magnetic-dipole transition probabilities, branching ratios and radiative lifetimes of several excited states of Tm3+. The classical McCumber theory was used to evaluate the emission cross-sections for the 3F4→3H6 transition at a wavelength of around 1.8µm. The characteristics of down-conversion luminescence in the visible range were studied by exciting Tm3+ ions into the 1G4 level. Furthermore the structure of this glass was analyzed by Raman spectroscopy.

Luminescence investigation on Eu–pillar[5]arene-based diglycolamide (DGA) complexes: Nature of the complex, Judd–Ofelt calculations and effect of ligand structure

An attempt was made to understand the insight of complexation of Eu3+ ion with three different structurally modified pillar[5]arene-based diglycolamides (P5DGA) and a comparison was also made with their molecular identity, TODGA. 7F0-5D2, 5G2,3,4, 5L6 transitions were observed in the absorption profiles while 5D0-7F0,1,2,3,4 transitions for emission spectra. Number of water molecules present in the primary coordination sphere of Eu3+ and the number of species were calculated from the life time measurement of the complexes under investigation. From the splitting pattern of the luminescence spectra of Eu3+ complex the point group symmetry around Eu3+ was found to be C4v. Judd-Offelt parameters (Ωλ, λ=2,4) were calculated for the complexes and correlated with the covalency of metal ligand bonds and long range ordering, respectively. It was demonstrated that preorganization of ligating moieties on the platform of pillararenes favoured the covalency of the metal–ligand bond in diglycolamides. Different photo physical properties such as radiative and non radiative life time, magnetic and electric dipole transition probabilities, branching ratio values for different transitions, quantum efficiency were evaluated for all the Eu3+-diglycolamide complexes.

Judd–Ofelt analysis of Tm3+ in La3Ga5.5Ta0.5O14 ceramic with granular structure

A Judd–Ofelt analysis was performed on a langatate (La3Ga5.5Ta0.5O14) translucent ceramic sample doped with 1 at% Tm3+. Due to the scattering of the transmitted light, the effective thickness of the sample is unknown and the absorption spectrum of Tm3+ in langatate ceramic sample is obtained in relative units. The absorption spectrum was calibrated using the magnetic-dipole contribution to the 3H6→3H5 transition. The Judd–Ofelt parameters obtained are: Ω2=2.65×10–20cm2, Ω4=0.80×10–20cm2, Ω6=1.86×10–20cm2. The electric-dipole and magnetic-dipole transition probabilities, radiative lifetimes and luminescence branching ratios were calculated. The calibration allowed the estimation of the ‘effective’ thickness of the ceramic sample which was approximately four times larger than the geometric thickness.

Growth and spectroscopic properties of samarium oxalate single crystals

Single crystals of samarium oxalate decahydrate were synthesized using single diffusion gel technique and the conditions influencing the size, shape and quality were optimized. Highly transparent crystals of size 3×2×1mm3 with a well defined hexagonal morphology were grown during a time period of two weeks. X ray powder diffraction analysis revealed that the grown crystals crystallize in the monoclinic system with space group P21/c and the proposed chemical formula and linkage of water molecules were confirmed using thermogravimetric analysis. The various functional groups of the oxalate ligand and the water of crystallization were identified by Fourier transform infrared spectroscopy. Spectroscopic investigations such as electric dipole transition probability, magnetic dipole transition probability and branching ratios of all possible transitions from 4G5/2 level of Sm3+ ions were estimated from the absorption spectra using JO theory. The spectroscopic analysis suggested that the crystal has a strong and efficient orange red emission. This is confirmed from the photoluminescence spectrum with a wavelength peak at 595nm and hence this promising emission can be effectively used for optical amplification.

Application of USDA and SDBA Hamiltonians in calculating the excited states of odd-A magnesium isotopes

In this study, we assess the accuracy of theoretical shell model in calculating the excited states in odd-A magnesium isotopes with neutron numbers between 9 and 15, on the basis of recently reported experimental results. The assessments rely on the calculations of the energy levels, reduced electric quadrupole transition probabilities, reduced magnetic dipole transition probabilities, and multipole mixing ratio. The theoretical results are based on the new sd-shell Universal Hamiltonian (USDA) and the realistic nucleon-nucleon interaction Bonn A Hamiltonian (SDBA). We show the area in which the two Hamiltonians are effective and demonstrate the possibility of confirming known states and suggesting new states.