Theoretical photoionization study of Ti9+ ion

2020 ◽  
Author(s):  
Hongbin Wang ◽  
Gang Jiang
Keyword(s):  
Cross Sections ◽  
Energy Levels ◽  
Radiative Transition ◽  
High Energy ◽  
Low Energy ◽  
Transition Rates ◽  
Channel Coupling ◽  
R Matrix ◽  
Good Consistency ◽  
Good Agreement

Photoionization (PI) of Ti<sup>9+</sup> ion is investigated by the Dirac R-matrix method. Multi-Configuration Dirac-Fock (MCDF) calculations are performed to construct accurate target functions. Good agreement of energy levels and radiative transition rates indicate the accuracy of target functions. PI cross sections show good consistency between length and velocity forms. The results are consistent with the previous theoretical values in high-energy regions. Partial waves contribution to the total PI cross sections are discussed for the ground and metastable states. Moreover, the PI cross sections are dominated by many resonance structures and affected by the channel coupling effects in low-energy region. In addition to providing data for the Opacity Project TOPbase, the present work promotes plasma simulation and diagnosis.

Comparison of reaction theories for multilevel interference—the 14C + p reactions

1969 ◽  
Vol 47 (24) ◽  
pp. 2763-2777 ◽  
Author(s):  
C. T. Tindle ◽  
E. Vogt
Keyword(s):  
Compound Nucleus ◽  
Cross Sections ◽  
Curve Fitting ◽  
Low Energy ◽  
Analytic Method ◽  
R Matrix ◽  
Strong Interference ◽  
S Matrix ◽  
Fitting Procedures ◽  
Good Agreement

A comparison is made between the R-matrix and S-matrix theories of low-energy compound nucleus resonances for the particular case of two-level interference. The (p,γ) and (p,n) cross sections of 14C for proton energies between 0.7 and 1.5 MeV are analyzed using both theories. The 15N compound nucleus in this region exhibits strong two-level interference. The two theories provide equally good fits to the data, but the parameters describing the compound-nucleus levels are quite different. A general analytic method of relating the two sets of parameters is derived and shown to give good agreement with the results obtained by curve-fitting procedures. Remarks are made concerning the general behavior of the parameters under strong interference conditions and also on the inclusion of many channels into the analysis.

Photoionization of Al X from ground state using the relativistic R-matrix close-coupling method

2014 ◽  
Vol 92 (3) ◽  
pp. 241-245 ◽  
Author(s):  
Liang Liang ◽  
Xu-yang Liu ◽  
Chao Zhou
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Energy Levels ◽  
Resonance Energy ◽  
Photoionization Cross Section ◽  
Rydberg Series ◽  
Close Coupling ◽  
R Matrix ◽  
Target States ◽  
Distorted Wave Method

The relativistic R-matrix method is used to calculate the total photoionization cross sections from the ground state 1s22s2 1S0 of Al X for photon energies ranges from the first ionization threshold to just above the eighth threshold of the residual ion Al XI. In this work, the relativistic distorted-wave method is employed to calculate the fine-structure energy levels and radial functions. The lowest eight level target states of Al XI are used in the photoionization calculations of Al X and should provide a reasonably complete database for practical application for photoionization cross section for Al X. The resonance energy levels and widths of 18 Rydberg series have been investigated.

Pseudopotential calculations of elastic scattering of low-energy electrons (< 20 eV) from neon atoms

1992 ◽  
Vol 70 (5) ◽  
pp. 305-310 ◽  
Author(s):  
Y. Frongillo ◽  
B. Plenkiewicz ◽  
P. Plenkiewicz ◽  
J.-P. Jay-Gerin
Keyword(s):  
Elastic Scattering ◽  
Energy Range ◽  
Cross Sections ◽  
Impact Energy ◽  
Theoretical Data ◽  
Low Energy ◽  
Pseudopotential Calculations ◽  
Low Energy Electrons ◽  
The Impact ◽  
Good Agreement

Pseudopotential calculations of phase shifts, differential, total, and momentum-transfer cross sections for electrons elastically scattered from neon atoms are reported in the impact energy range 0–20 eV. The results are found to be in very good agreement with existing experimental and other theoretical data.

scholarly journals Ruminal Microbiota and Fermentation in Response to Dietary Protein and Energy Levels in Weaned Lambs

Animals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 109 ◽  
Author(s):  
Xiaokang Lv ◽  
Kai Cui ◽  
Minli Qi ◽  
Shiqin Wang ◽  
Qiyu Diao ◽  
...  
Keyword(s):  
Growth Performance ◽  
Energy Levels ◽  
High Energy ◽  
Metabolizable Energy ◽  
Low Energy ◽  
Dietary Energy ◽  
Ruminal Fermentation ◽  
Protein Levels ◽  
Energy Group ◽  
Low Energy Diet

Supplying sufficient nutrients, such as dietary energy and protein, has a great effect on the growth and rumen development of ruminants. This study was conducted to evaluate the effects of dietary energy and protein levels on growth performance, microbial diversity, and structural and physiological properties of the rumen in weaned lambs. A total of 64 two-month-old Hu lambs were randomly allotted to 2 × 2 factorial arrangements with four replicates and with four lambs (half male and half female) in each replicate. The first factor was two levels of dietary metabolizable energy (ME) density (ME = 10.9 MJ/Kg or 8.6 MJ/Kg), and the second factor was two levels of dietary crude protein (CP) content (CP = 15.7% or 11.8%). The trial lasted for 60 days. A low dietary energy level restrained the growth performance of lambs (p < 0.05). The ruminal concentration of acetate and the ratio of acetate to propionate increased but the propionate concentration decreased significantly with the low energy diet. However, the rumen morphology was not affected by the diet energy and protein levels. Moreover, a low energy diet increased ruminal bacterial diversity but reduced the abundance of the phylum Proteobacteria (p < 0.05) and genus Succinivibrionaceae_uncultured (p < 0.05), which was associated with the change in ruminal fermentation phenotypes. By indicator species analysis, we found three indicator OTUs in the high energy group (Succinivibrionaceae_uncultured, Veillonellaceae_unclassified and Veillonellaceae_uncultured (p < 0.01)) and two indicator OTUs in the low energy group (Bacteroidales_norank and Lachnospiraceae_uncultured (p < 0.01)). In conclusion, these findings added new dimensions to our understanding of the diet effect on rumen microbial community and fermentation response, and are of great significance for establishing the optimal nutrient supply strategy for lambs.

scholarly journals Benchmarking Current Capabilities for the Generation of Excitation and Photoionisation Atomic Data

Galaxies ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 90 ◽  
Author(s):  
Catherine Ramsbottom ◽  
Connor Ballance ◽  
Ryan Smyth ◽  
Andrew Conroy ◽  
Luis Fernández-Menchero ◽  
...  
Keyword(s):  
Numerical Methods ◽  
Cross Sections ◽  
Transition Probabilities ◽  
Energy Levels ◽  
Radiative Transition ◽  
Atomic Data ◽  
High Quality ◽  
Astronomical Instruments ◽  
First Time ◽  
Line Strengths

The spectra currently emerging from modern ground- and space-based astronomical instruments are of exceptionally high quality and resolution. To meaningfully analyse these spectra, researchers utilise complex modelling codes to replicate the observations. The main inputs to these codes are atomic data such as excitation and photoionisation cross sections, as well as radiative transition probabilities, energy levels, and line strengths. In this publication, the current capabilities of the numerical methods and computer packages used in the generation of these data are discussed. Particular emphasis is given to Fe-peak species and the heavy systems of tungsten and molybdenum. Some of the results presented to highlight certain issues and/or advances have already been published in the literature, while other sections present new recently evaluated atomic data for the first time.

On the constraints that duality imposes on the broken SU(6)w structure of the baryonic resonance photocouplings

1979 ◽  
Vol 57 (6) ◽  
pp. 815-823
Author(s):  
C. Avilez ◽  
G. Cocho
Keyword(s):  
High Energy ◽  
Low Energy ◽  
Meson Photoproduction ◽  
Baryonic Resonance ◽  
Energy Constraints ◽  
Natural Parity ◽  
Parity Exchange ◽  
Good Agreement

The absence of exotics and the natural parity exchange dominance in the t-channel, in high energy meson photoproduction of nucleons impose, via duality, restrictions on the baryonic resonance photocouplings. In a broken SU(6)w parametrization these constraints allow different couplings for the [Formula: see text] and [Formula: see text] baryonic resonances and impose relations between the transitions to the 70 and 56SU(6)W representations. It is shown that the low energy baryonic resonance photocouplings are in good agreement with these high energy constraints.

Energy levels and radiative transition rates for Ba XLVIII

2016 ◽  
Vol 107 ◽  
pp. 367-405 ◽  
Author(s):  
Indu Khatri ◽  
Arun Goyal ◽  
Sunny Aggarwal ◽  
A.K. Singh ◽  
Man Mohan
Keyword(s):  
Energy Levels ◽  
Radiative Transition ◽  
Transition Rates

scholarly journals Interpretation of the spectrum of Pb(II). Theoretical transition probabilities and lifetimes

2001 ◽  
Vol 79 (7) ◽  
pp. 999-1009 ◽  
Author(s):  
C Colón ◽  
A Alonso-Medina
Keyword(s):  
Transition Probabilities ◽  
Energy Levels ◽  
Radiative Transition ◽  
Least Square ◽  
Large Contribution ◽  
Hartree Fock ◽  
Forbidden Transition ◽  
Method Of Least Square ◽  
Experimental Values ◽  
Good Agreement

Radiative transition probabilities for 190 lines arising from the ns 2S1/2, np 2P1/2,3/2, nd 2D3/2,5/2, nf 2F5/2,7/2, and 6p2 (4P1/2,3/2,5/2, 2D3/2,5/2, 2P1/2,3/2, and 2S1/2) levels of Pb(II) have been calculated. Lifetimes of the above mentioned levels have been determined from the present transition probabilities. These values were obtained in intermediate coupling (IC) and using ab initio relativistic Hartree-Fock calculations. For the IC calculations, we use the standard method of least-square fitting of experimental energy levels by means of computer codes from Cowan. The results of calculations for radiative transition probabilities and excited states lifetimes are presented and compared with the experimental results present in the literature and with other theoretical values. There is generally good agreement between our values and the experimental data available. Analysis of the interaction shows that the level 4P5/2 of the 6s6p2 configuration presents a large contribution to the 2D5/2 level of the 6s26d configuration. This result explains the good agreement between our result and the experimental values obtained to the observed as the 6s6p2 4P5/2 – 6s 25f2F7/2 dipole-forbidden transition. PACS Nos.: 32.70^*, 32.70Fw, 32.70Cs

Crude protein requirements of large frame cattle fed two levels of energy as weaned calves or as backgrounded yearlings

1993 ◽  
Vol 73 (2) ◽  
pp. 315-325 ◽  
Author(s):  
J. J. McKinnon ◽  
R. D. H. Cohen ◽  
D. A. Christensen ◽  
S. D. M. Jones
Keyword(s):  
Energy Balance ◽  
Key Words ◽  
Crude Protein ◽  
Energy Levels ◽  
Average Daily Gain ◽  
High Energy ◽  
Carcass Composition ◽  
Low Energy ◽  
Protein Requirements ◽  
Daily Gain

Two trials were conducted to determine the crude protein (CP) requirements of large-frame (LF) cattle managed under two regimes and fed one of two energy levels. Trial 1 involved 216 recently weaned LF calves, while trial 2 involved 192 LF backgrounded yearling steers. In each trial, the cattle were fed diets formulated to one of two energy levels (11.17 and 11.88 MJ ME kg−1 DM) and one of six CP levels (11, 13, 15, 16, 17 and 19% DM basis). High-energy feeding increased (P < 0.05), average daily gain (ADG), average daily carcass gain (ADCG) and average daily fat gain (ADFG) of weaned calves but did not influence the performance of the backgrounded yearlings. Weaned calves fed 16, 17 or 19% CP had higher (P < 0.05) ADG than those fed 11%, while those fed 16% CP exhibited increased (P < 0.05) ADFG. ADG and ADCG of weaned calves and backgrounded yearlings and ADFG of weaned calves fed low-energy diets increased (P < 0.05) linearly with increasing dietary CP concentration. Daily carcass lean gain of weaned calves fed low-energy diets decreased in a quadratic manner (P < 0.05) as dietary CP level increased. No influence of dietary CP concentration was observed on carcass tissue gain of the backgrounded yearlings. It was concluded that energy balance of animals fed low-energy diets improved with CP supplementation and that current NAS-NRC (1984) CP requirements accurately predict performance of LF cattle. Key words: Steers, growth, carcass composition, energy, crude protein

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