Level Width Research Articles

Seasonal variations of macrozoobenthic community trophic structure in the waters adjacent to the seaweed beds of Dalian Island in the North Yellow Sea.

To investigate the effects of algal detritus export on the trophic structure of macrozoobenthic community in the adjacent benthic habitat during the bloom and decline of macroalgae, we collected macrozoobenthos from the adjacent sea area of Dalian Island in the North Yellow Sea in May (the algal bloom period) and August (the algal decay period) of 2020. We quantifyied the seasonal changes in the trophic structure of macrozoobenthic community by using carbon and nitrogen stable isotope techniques. Results showed that δ13C and δ15N values of macrozoo-benthos in May ranged from -23.14‰ to -14.24‰, 6.21‰ to 12.90‰, respectively, and -22.36‰ to -14.13‰, 5.33‰ to 12.00‰, respectively in August. Results of PERMANOVA analysis showed that δ13C values of macrozoobenthos differed significantly between the two months, while δ15N values were not significantly different. Based on the Euclidean distance, the macrozoobenthic communities in both months could be classified into five trophic functional groups. The trophic levels of macrozoobenthos ranged from 2.00 (Nitidotellina minuta) to 3.97 (Glycera onomichiensis) in May and from 2.00 (N. minuta) to 3.96 (G. onomichiensis) in August. The δ13C range, δ15N range, mean centroid distance, total area and corrected standard ellipse areas which represented community trophic structure indices in August were higher than those in May. Our results indicated that the trophic diversity level and trophic niche width of the macrozoobenthic community in the adjacent sea area of the seaweed bed were higher in the algal decline season.

Impacts of uneven thickness on mixture nanoliquid flow over a slendering stretched sheet in company of a magnetic field

A numerical analysis has been presented for stream of a mixture nanoliquid over a slendering stretched sheet in company of an external magnetic meadow under boundary layer approximations. This investigation is performed to look at the impacts of variable thickness on balanced two-dimensional (2D) flow of a hybrid nanofluid under border-level approximations as it has wider technological applications in various industries. A variable magnetic field has been considered here. An effort has been taken in this piece to report the joint impacts of variable thickness and MHD on hybrid nanoliquid flow over a slendering stretched sheet as no one has reported such effects. Here lies the novelty of the work. By applying appropriate similarity transformations, the leading partial differential equations (PDEs) are converted to ordinary differential equations (ODEs) and the solutions of the nonlinear equations are subsequently obtained numerically using shooting technique. To hold up the soundness of the statistical outcomes, an assessment is completed with the accessible known outcomes for a few meticulous cases of this study. The consequences of a variety of parameters on motion of fluid and heat transport are analyzed and talked about exhaustively with the help of tabular and graphical representations. It is found that Lorentz force slows down the border-level flow and thickens the momentum border level width. Skin-friction coefficient reduces with the decreasing values of m for [Formula: see text] which is obvious as superior values of m help the liquid to move faster over the exterior and the thickness of the boundary layer augments with the mounting values of m ([Formula: see text]). Thus, it can be concluded that the fluid motion is controlled by the power-law index m ([Formula: see text]) since the motion slows down for [Formula: see text] and goes faster for [Formula: see text].

Correlation Between Depression Level and Red Blood Cell Distribution Width (RDW) and Erythrocyte Sedimentation Rate (ESR) in Chronic Kidney Disease (CKD) Patients Undergoing Regular Hemodialysis at Haji Adam Malik General Hospital Medan

Introduction: Chronic Kidney Disease are related to inflammation and stress levels therefore depression is a predictor that will increase the morbidity and mortality of patients with chronic kidney disease undergoing hemodialysis. Method: This research is an analytical study with a cross-sectional design which carried out in Januari until February 2023, at Hemodialysis Installation of RSUP. H. Adam Malik. To analyze the correlation between the Depression Level and Red Blood Cell Distribution Width (RDW) and Erythrocyte Sedimentation Rate (ESR), the Pearson correlation test was used if the data was normally distributed. If the data is not normally distributed, Spearman's correlation test is performed. Statistical analysis using 95% confidence level (p<0.05). Results: In this research, demographic characteristics of 85 patients with mean age of the patients was 49.56 years old with a standard deviation of 13.46. Based on Spearman rho test it was found that there was a significant correlation between RDW and the BDI II score with p value 0.003. The degree of correlation or r value was 0.318. This indicates that there is a weak correlation between the RDW score and the BD II score. Based on Pearson test it was found that there was a significant correlation between ESR and the BDI II score with p value 0.009. The degree of correlation or r value was 0.280. This indicates that there is a weak correlation between the ESR value and the BD II score. Conclusion: Level of depression were found to be correlated with Red Blood Cell Distribution Width (RDW) and Erythrocyte Sedimentation Rate (ESR) in CKD patients whose undergoing regular hemodialysis.

Novel multilevel inverter topology with low switch count

Abstract This paper aims to introduce a new multilevel inverter topology less number of switches and gate drivers with a hybrid control method. In the proposed topology three kinds of voltage sources are utilized in the topology. A combination of these voltage sources, switches, and two H-bridges derived a new topology. Moreover, combining the nearest level and pulse width modulation created an efficient way to control the proposed topology which is described in this paper. Equations to determine the number of components and total standing voltage of the proposed multilevel is presented. A comprehensive comparison between the proposed topology and other best topologies is made. Additionally, the simulation results which are obtained by PSCAD/EMTDC and experimental results are in accordance with the theory. The proposed multilevel inverter with a hybrid control method has less number of switches, gate drivers, and low THD.

Estimating river bathymetry from multisource remote sensing data

River bathymetry is a key variable in estimating river discharge by remote sensing. However, traditional methods of mapping river bathymetry are expensive and time-consuming, which hinders the estimation of river discharge. In this study, we propose and test a method for estimating river bathymetry by combining remotely sensed observations of water level (z) and river width (w) with a nonlinear z-w relationship derived from a generalized channel cross-sectional shape. The results from five reaches of the upper Yangtze River show that the absolute relative error for the estimate is between 1.25% and 6.18%, indicating the ability of this method to provide accurate estimates. The channel exposure (e) is the main limitation of the proposed method, and the river bathymetry estimates improve significantly with increasing e. For the upper Yangtze River, averaging reaches over an appropriate length can reduce variability in river bathymetry estimate, especially when data are reach-averaged over a length of 10 km. Considering that a priori bathymetric information is not required and its computational process is relatively simple, the proposed method could open up the possibility of bathymetry modeling of global rivers.

Quantum Phase Diagram and Spontaneously Emergent Topological Chiral Superconductivity in Doped Triangular-Lattice Mott Insulators.

The topological superconducting state is a highly sought-after quantum state hosting topological order and Majorana excitations. In this Letter, we explore the mechanism to realize the topological superconductivity (TSC) in the doped Mott insulators with time-reversal symmetry (TRS). Through large-scale density matrix renormalization group study of an extended triangular-lattice t-J model on the six- and eight-leg cylinders, we identify a d+id-wave chiral TSC with spontaneous TRS breaking, which is characterized by a Chern number C=2 and quasi-long-range superconducting order. We map out the quantum phase diagram with by tuning the next-nearest-neighbor (NNN) electron hopping and spin interaction. In the weaker NNN-coupling regime, we identify a pseudogaplike phase with a charge stripe order coexisting with fluctuating superconductivity, which can be tuned into d-wave superconductivity by increasing the doping level and system width. The TSC emerges in the intermediate-coupling regime, which has a transition to a d-wave superconducting phase with larger NNN couplings. The emergence of the TSC is driven by geometrical frustrations and hole dynamics which suppress spin correlation and charge order, leading to a topological quantum phase transition.

Quantum-well states at the surface of a heavy-fermion superconductor

Two-dimensional electronic states at surfaces are often observed in simple wide-band metals such as Cu or Ag (refs. 1–4). Confinement by closed geometries at the nanometre scale, such as surface terraces, leads to quantized energy levels formed from the surface band, in stark contrast to the continuous energy dependence of bulk electron bands2,5–10. Their energy-level separation is typically hundreds of meV (refs. 3,6,11). In a distinct class of materials, strong electronic correlations lead to so-called heavy fermions with a strongly reduced bandwidth and exotic bulk ground states12,13. Quantum-well states in two-dimensional heavy fermions (2DHFs) remain, however, notoriously difficult to observe because of their tiny energy separation. Here we use millikelvin scanning tunnelling microscopy (STM) to study atomically flat terraces on U-terminated surfaces of the heavy-fermion superconductor URu2Si2, which exhibits a mysterious hidden-order (HO) state below 17.5 K (ref. 14). We observe 2DHFs made of 5f electrons with an effective mass 17 times the free electron mass. The 2DHFs form quantized states separated by a fraction of a meV and their level width is set by the interaction with correlated bulk states. Edge states on steps between terraces appear along one of the two in-plane directions, suggesting electronic symmetry breaking at the surface. Our results propose a new route to realize quantum-well states in strongly correlated quantum materials and to explore how these connect to the electronic environment.

Influence of single adsorbed atoms on charge exchange during ion-surface collisions

Partial and final projectile charge states are theoretically analyzed after ${\mathrm{Li}}^{+}$ ions frontally collide with a single-layer graphene surface with potassium atoms adsorbed on it, in the very low deposition limit where the adsorbed atoms negligibly interact with each other. We applied a model based on first principles that accounts for all the details of the surface and is used to describe the resonant charge exchange processes occurring in binary collisions between the projectile and the adsorbate, and between the projectile and the C atoms of the graphene surface located in the surroundings of the adsorption site. Completely different neutral fraction dependences with the outgoing velocity are found for the projectiles scattered by the adsorbate and by carbon atoms located far from the adsorbed atom. In addition, an important influence of the adsorbate is perceived in the neutralization of projectiles colliding with the first and second set of carbon atoms nearest to the adsorption site. For C atoms located at middle-range distances (\ensuremath{\sim}6.7 \AA{}), the final charge state of the projectile is not affected by the adsorbate presence, even when an effective interaction between the projectile and the K adsorbed atom is revealed via appreciable projectile level widths.

Tunable spectral narrowing enabling the functionality of graphene qubit circuits at room temperature

Electrically controllable quantum coherence in quantum dot clusters and arrays based on graphene stripes with zigzag atomic edges (ZZ-stripes) is studied using the Dirac equation and S-matrix technique. We find that respective multiqubit circuits promise stable operation up to room temperatures when the coherence time is prolonged up by a few orders of magnitude through the intrinsic spectral narrowing owing to electron transport between at bands in adjacent sections. Respectively, the coupling of qubits to a noisy environment is diminished, while the inelastic electron-phonon scattering is suppressed. The Stark splitting technique enables a broad range of operations such as all{electrical tuning of the energy level positions and width, level splitting, controlling of the inter-qubit coupling, and the coherence time. At the resonant energies, the phase coherence spreads over thousands of periods. Such phenomena potentially can be utilized in quantum computing and communication applications at room temperature.

Can room-temperature data for tunneling molecular junctions be analyzed within a theoretical framework assuming zero temperature?

Routinely, experiments on tunneling molecular junctions report values of conductances (GRT) and currents (IRT) measured at room temperature. On the other hand, theoretical approaches based on simplified models provide analytic formulas for the conductance (G0K) and current (I0K) valid at zero temperature. Therefore, interrogating the applicability of the theoretical results deduced in the zero-temperature limit to real experimental situations at room temperature (i.e., GRT ≈ G0K and IRT ≈ I0K) is a relevant aspect. Quantifying the pertaining temperature impact on the transport properties computed within the ubiquitous single-level model with Lorentzian transmission is the specific aim of the present work. Comprehensive results are presented for broad ranges of the relevant parameters (level's energy offset ε0 and width Γa, and applied bias V) that safely cover values characterizing currently fabricated junctions. They demonstrate that the strongest thermal effects occur at biases below resonance (2|ε0| - δε0 - 0.3 ≲ |eV| - 0.3 ≲ 2|ε0|). At fixed V, they affect an ε0-range whose largest width δε0 is about nine times larger than the thermal energy (δε0 ≈ 3πkBT) at Γa → 0. The numerous figures included aim to convey a quick overview on the applicability of the zero-temperature limit to a specific real junction. In quantitative terms, the conditions of applicability are expressed as mathematical inequalities involving elementary functions. They constitute the basis of a proposed interactive data-fitting procedure, which aims to guide experimentalists interested in data processing in a specific case.

Modified Coronally Advanced Tunnel Technique in the Treatment of Multiple Gingival Recessions Associated with and without Non Carious Cervical Lesions- A Prospective Clinical Study

Introduction: Gingival Recession (GR) can be associated to periodontal disease-causing dentinal hypersensitivity, root caries and even aesthetic problems. A combination of the Modified Coronally Advanced Tunnel Technique (MCAT) with Subepithelial Connective Tissue Graft (SCTG) can be considered an option for treating multiple GR. Aim: To evaluate the effectiveness of root coverage using MCAT along with SCTG in multiple GR with and without Non Carious Cervical Lesions (NCCL). Materials and Methods: The present prospective clinical study was conducted in Department of Periodontology at Vishnu Dental College, Bhimavaram, Andhra Pradesh, India, from June 2018 to December 2019. A total of 24 patients seeking treatment for multiple GR in which 12 patients with recessions alone and 12 patients associated with NCCL were included in the study. Clinical measurements of Pocket Probing Depth (PPD), Clinical Attachment Level (CAL), Recession Depth (RD) and Recession Width (RW), Width of Keratinised Tissue (KTW), Gingival Thickness (GT), Pink Aesthetic Score and hypersensitivity scores were determined at baseline and six months. Descriptive statistics, Independent samples t-test, repeated measures Analysis of Variance (ANOVA), and paired t-tests were used in data analysis. The p-value <0.05 would be considered statistically significant. Results: The mean age of the patients was 30±10.16 years. The study group comprised of 18 males and six females, constituting male to female ratio as 3:1. A statistical significance in reduction of recession was seen from baseline to six months in both control and test groups which are (9.67±1.15 mm to 0.92±1.67 mm) and (10.92±0.99 mm to 0.67±1.23 mm) respectively and increase in KTW was seen from baseline to six months in both groups which are (1.58±0.66 mm to 3.2±0.75 mm) and (1.75±0.45 mm to 3.50±0.67 mm), respectively. However, a statistically significant decrease in hypersensitivity was observed in the MCAT+SCTG+NCCL group. Conclusion: The results of the present study suggested that MCAT could be opted as a treatment of choice for multiple GR associated with non carious lesions, as well in terms of aesthetics and hypersensitivity.

Novel Apodized Fiber Bragg Grating Applied for Medical Sensors: Performance Investigation

Sensors play an important role in shaping and monitoring human health. Exploration of methods to use Fiber Bragg Grating (FBG) with enhanced sensitivity has attracted great interest in the field of medical research. In this paper, a novel apodization function is proposed and performance evaluation and optimization of the same have been made. A comparison was conducted between various existing apodization functions and the proposed one based on optical characteristics and sensor parameters. The results evince the implementation of the proposed apodization function for vital sign measurement. The optical characteristics considered for evaluation are Peak Resonance Reflectivity level, Side Lobes Reflectivity level and Full Width Half Maximum (FWHM). The proposed novel apodization novel function has better FWHM, which is narrower than the FWHM of uniform FBG. Sensor characteristics like a quality parameter, detection accuracy and sensitivity also show improvement. The proposed novel apodization function is demonstrated to have a better shift in wavelength in terms of temperature and pulse measurement than the existing functions. The sensitivity of the proposed apodized function is enhanced with a Poly-dimethylsiloxane coating of varying thickness, which is 6 times and 5.14 times greater than uniform Fiber Bragg grating and FBG with the proposed novel apodization function, respectively, enhancing its utilization in the field of medicine.

Shot noise in resonant tunneling: Role of inelastic scattering

We study the influence of inelastic processes on shot noise and the Fano factor for a one-dimensional double-barrier structure, where resonant tunneling takes place between two terminals. Most studies to date have found, by means of various approximate or phenomenological methods, that shot noise is insensitive to dephasing caused by inelastic scattering. In this paper, we explore the status of this statement by deriving a general Landaur-B\"uttiker-type formula that expresses the current noise and Fano factor in a one-dimensional conductor through inelastic scattering amplitudes. For a double-barrier structure, exact scattering amplitudes are calculated in the presence of a time-dependent potential. As an example of dephasing potential, we consider the one induced by equilibrium phonons. We calculate transmission coefficients of a double-barrier structure for these two types of phonon-induced dephasing. In the case of diffusive phase relaxation valid for one dimension phonons, the resonant level has a Lorentzian shape. For phonons whith high dimensions logarithmic dephasing realized which leads to an unusual shape of the size-quantized level characterized by the two energy scales. We further calculate the Fano factor for these types of dephasing, using exact expressions for inelastic transmission and reflection amplitudes. It turned out that when an integer number of levels fall into the energy window of width eV, where V is the voltage applied to the structure, the Fano factor is really insensitive to inelastic processes inside the structure and coincides with the prediction of phenomenological models with an accuracy of small corrections depending on these processes. On the contrary, at low voltages, when the eV window is smaller than the level width, this dependence is particularly pronounced and the phenomenological formula does not work.

K shell fluorescence parameters of some elements at 59.54 keV: Experimental and theoretical results

Kα, Kβ and total K X-ray fluorescence cross-sections, K shell fluorescence yields, Kβ/Kα X-ray intensity ratios, K shell level widths, K shell life times, K to L shell vacancy transfer probabilities, K shell jump ratios, Auger electrons emission ratios and excitation factors for some elements in the atomic number range 22 ≤ Z ≤ 48 have been investigated. A Si(Li) detector and Am-241 annular radioactive source were used in the measurements. The obtained experimental data were crosschecked with theoretically calculated results and other available experimental results from the literature. It was observed that there is a good agreement between them within experimental uncertainties.

New Insights into the Lamb Shift: The Spectral Density of the Shift

In an atom, the interaction of a bound electron with the vacuum fluctuations of the electromagnetic field leads to complex shifts in the energy levels of the electron, with the real part of the shift corresponding to a shift in the energy level and the imaginary part to the width of the energy level. The most celebrated radiative shift is the Lamb shift between the 2s1/2 and the 2p1/2 levels of the hydrogen atom. The measurement of this shift in 1947 by Willis Lamb Jr. proved that the prediction by Dirac theory that the energy levels were degenerate was incorrect. Hans Bethe’s non-relativistic calculation of the shift using second-order perturbation theory demonstrated the renormalization process required to deal with the divergences plaguing the existing theories and led to the understanding that it was essential for theory to include interactions with the zero-point quantum vacuum field. This was the birth of modern quantum electrodynamics (QED). Numerous calculations of the Lamb shift followed including relativistic and covariant calculations, all of which contain a nonrelativistic contribution equal to that computed by Bethe. The semi-quantitative models for the radiative shift of Welton and Power, which were developed in an effort to demonstrate physical mechanisms by which vacuum fluctuations lead to the shift, are also considered here. This paper describes a calculation of the shift using a group theoretical approach which gives the shift as an integral over frequency of a function, which is called the “spectral density of the shift.“ The energy shift computed by group theory is equivalent to that derived by Bethe yet, unlike in other calculations of the non-relativistic radiative shift, no sum over a complete set of states is required. The spectral density, which is obtained by a relatively simple computation, reveals how different frequencies of vacuum fluctuations contribute to the total energy shift. The analysis shows, for example, that half the radiative shift for the ground state 1S level in H comes from virtual photon energies below 9700 eV, and that the expressions of Power and Welton have the correct high-frequency behavior, but not the correct low-frequency behavior, although they do give approximately the correct value for the total shift.

Temperature-dependent relative self-absorption measurements in 27Al

Nuclear resonance fluorescence measurements provide direct sensitivity to ground-state transition widths by probing the photoexcitation process of nuclear resonances. A technique in Relative Self-Absorption (RSA) measurements, in which measurements are done at multiple absorber temperatures, was developed and tested with 27Al at the Darmstadt High Intensity Photon Setup of the Superconducting Darmstadt Linear Accelerator. The advantage of this technique, over the regular RSA, is the possibility to overcome the need for theory input on the effective temperatures and the uncertainties that they introduce in the measured level widths. The technique and the preliminary results of the first test-measurements are presented in this proceedings.

Bond behavior of NSM strips in corroded/cracked reinforced concrete

There is limited research on the bond behavior of NSM strips embedded in corroded/cracked reinforced concrete (RC). Therefore, this study was initiated to evaluate the bond behavior between corroded/cracked RC and NSM strips. The test specimens consist of two concrete prisms (reinforced and plain) mounted from two opposite sides with NSM strips. After 28 days of moisture curing, twenty-four specimens were immersed in saline solution and were exposed to three accelerated corrosion levels with steel mass loss of 2.2, 4.1 and 8.1%. The bond behavior was evaluated using double shear pullout test. The study showed that the corrosion cracks increased with the increase of corrosion level. The maximum crack width reached 0.91 mm at corrosion level 3. The mass loss of the corroded reinforcing steel increased from 2.1% for corrosion level 1–8.3% for corrosion level 3. The bond strength between NSM strips and corrosion cracked concrete was significantly decreased with maximum reduction of 48% at corrosion level 3. The other bond characteristics including maximum slip, bond toughness and bond stiffness were also decreased with corrosion with percent reduction of (31, 67 and 35%), respectively. The failure mode of the bond between NSM strips and corrosion cracked concrete was splitting of concrete. Theoretical models were proposed for predicting the bond strength between NSM strips and corrosion cracked concrete based on corrosion level and crack width. The proposed models showed excellent agreement with the experimental results from the current study and the literature.

The effect of loading time on marginal bone change of implants immediately placed after extraction: a retrospective study

BackgroundThe purpose of this study is to compare and analyze the treatment outcomes between two groups which are both immediately placed implant cases, one is immediate loading, and the other is conventional loading group.MethodsMedical records of the patients who underwent implant treatment which were immediately placed after tooth extraction were analyzed. Demographic data were collected and by using periapical or panoramic radiographic image, marginal bone level and distant crestal bone level were measured. Marginal bone change over time was analyzed and compared between immediate loading group and conventional loading group.ResultsA total of 71 patients, 112 immediately placed implants after tooth extraction were initially involved. Measuring was done with implants which had not failed (81). 10 implants were had failed and removed. The others were excluded because of follow-up loss, absence of radiographic image, etc. Demographic data were collected, and measured values were averaged at each follow-up and showed in linear graphs.ConclusionsIn case of immediate implantation of dental implant after extraction, loading time could affect marginal bone level or biological width of the implant. Immediate loading group showed 0.92 mm (mean value) more bone loss compared to conventional loading group at bone–implant contact points 24 months after implantation. At distant crestal points, there was no noticeable difference in bone change pattern between two groups.

Mesenchymal stem cell therapy on top of triple therapy with remdesivir, dexamethasone, and tocilizumab improves PaO2/FiO2 in severe COVID-19 pneumonia.

BackgroundDespite patients with severe coronavirus disease (COVID-19) receiving standard triple therapy, including steroids, antiviral agents, and anticytokine therapy, health condition of certain patients continue to deteriorate. In Taiwan, the COVID-19 mortality has been high since the emergence of previous variants of this disease (such as alpha, beta, or delta). We aimed to evaluate whether adjunctive infusion of human umbilical cord mesenchymal stem cells (MSCs) (hUC-MSCs) on top of dexamethasone, remdesivir, and tocilizumab improves pulmonary oxygenation and suppresses inflammatory cytokines in patients with severe COVID-19.MethodsHospitalized patients with severe or critical COVID-19 pneumonia under standard triple therapy were separated into adjuvant hUC-MSC and non-hUC-MSC groups to compare the changes in the arterial partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ratio and biological variables.ResultsFour out of eight patients with severe or critical COVID-19 received either one (n = 2) or two (n = 2) doses of intravenous infusions of hUC-MSCs using a uniform cell dose of 1.0 × 108. Both high-sensitivity C-reactive protein (hs-CRP) level and monocyte distribution width (MDW) were significantly reduced, with a reduction in the levels of interleukin (IL)-6, IL-13, IL-12p70 and vascular endothelial growth factor following hUC-MSC transplantation. The PaO2/FiO2 ratio increased from 83.68 (64.34–126.75) to 227.50 (185.25–237.50) and then 349.56 (293.03–367.92) within 7 days after hUC-MSC infusion (P < 0.001), while the change of PaO2/FiO2 ratio was insignificant in non-hUC-MSC patients (admission day: 165.00 [102.50–237.61]; day 3: 100.00 [72.00–232.68]; day 7: 250.00 [71.00–251.43], P = 0.923).ConclusionTransplantation of hUC-MSCs as adjunctive therapy improves pulmonary oxygenation in patients with severe or critical COVID-19. The beneficial effects of hUC-MSCs were presumably mediated by the mitigation of inflammatory cytokines, characterized by the reduction in both hs-CRP and MDW.

THEORETICAL STUDYING SPECTRAL CHARACTERISTICS OF Tm ATOM WITHIN OPTIMIZED RELATIVISTIC MANY-BODY THEORY

Theoretical studying Rydberg spectrum of complex lanthanide atom of Tm has been performed within the relativistic many-body perturbation theory and generalized relativistic energy approach. The zeroth approximation of the relativistic perturbation theory is provided by the optimized Dirac-Kohn-Sham-Breit ones. Optimization has been fulfilled by means of introduction of the special gauge parameter to the Fock and Kohn-Sham exchange potentials and further minimization of the gauge-non-invariant contributions into radiation width of atomic levels with using relativistic orbital sets, generated by the corresponding zeroth approximation Hamiltonian. The calculated energies and widths of autoionization resonant states 4f--1j 6s(J12)nsnp[J] of the Tm atom with n=25-35 are presented and compared with known theoretical results, received within other approaches. Two main types of the Rydberg autoionization resonances decay, namely, the classic Beutler-Fano decay channel and a new Ivanov et al reorientation-type decay channel ar4e studied. It is noted that, for example, for autoionization resonant states with the considered values of n, the decay of resonances occurs along both channels, and it is extremely difficult to understand a priori which of them is dominant.