Accurate transition probabilities for the 2s2 1S - 2s2p 1P transition in Be I and B II

1999 ◽  
Vol 77 (2) ◽  
pp. 137-143 ◽  
Author(s):  
R E Irving ◽  
M Henderson ◽  
L J Curtis ◽  
I Martinson ◽  
P Bengtsson
Keyword(s):  
Decay Curve ◽  
Transition Probabilities ◽  
Theoretical Calculations ◽  
Transition Probability ◽  
Lifetime Measurements ◽  
Beam Foil

Transition probability determinations are reported for the 2s2 1S - 2s2p 1P transition in Be I and B II, based on lifetime measurements made by beam-foil excitation. The lifetimes were extracted by the ANDC method, which incorporates cascade-related decay curves into the analysis of the primary decay curve, thus accounting for the effects of cascade repopulation. The results are of higher precision than earlier measurements and improve the agreement with recent theoretical calculations. PACS No.: 32.70Cs

scholarly journals Committee 2: Transition Probabilities

1970 ◽  
Vol 14 (1) ◽  
pp. 127-128
Author(s):  
R. H. Garstang
Keyword(s):  
Transition Probabilities ◽  
Conference Report ◽  
Atomic Transition ◽  
National Bureau ◽  
Complete Coverage ◽  
Lifetime Measurements ◽  
Forbidden Transition ◽  
Beam Foil ◽  
Supply Information

A very great deal of work has been done during the last three years on the determination of atomic transition probabilities, and complete coverage here is impossible. Wiese and his staff at the National Bureau of Standards, Washington, have continued to collect all numerical results, and they can supply information as to what is available for any particular atom. They have published (1) a critical compilation of atomic transition probabilities for the atoms sodium to calcium (inclusive) in essentially the same way as an earlier compilation covered hydrogen to neon. At the time of writing a complete new bibliography is also in preparation (2), which will be published as NBS Special Publication 320 and which is complete up to June 1969. Review articles published include that of Layzer and Garstang (3) on theoretical allowed and forbidden transition probabilities, and the two volume conference report (4) covers beam foil spectroscopy (including lifetime measurements) in some detail. A fairly complete review of forbidden line transition probabilities was given by Garstang (5), where references to many original papers may be found. In the following we shall confine ourselves to mentioning a few areas of particular interest; detailed references can be traced through the bibliographies, reviews and abstracting journals.

Beam-foil lifetime measurements in Pb III and Pb IV

1988 ◽  
Vol 66 (5) ◽  
pp. 402-404 ◽  
Author(s):  
W. Ansbacher ◽  
E. H. Pinnington ◽  
J. A. Kernahan
Keyword(s):  
Wavelength Range ◽  
Decay Curve ◽  
Polarization Model ◽  
Lifetime Measurements ◽  
Recent Calculation ◽  
Core Correlation ◽  
Intensity Decay ◽  
Beam Foil ◽  
Good Agreement

Beam-foil intensity decay curves for transitions in the wavelength range from 900 to 2200 Å are used to derive the lifetimes of the 6s6p1P1 and 3P1 6s6d1D2, 6s7s1S0, and 6p21D2 levels of Pb III, and the 6p2P1/2 and 2P3/2, 6d2D3/2 and 2D5/2, 7s2S1/2, and 5d96s22D3/2 levels of Pb IV, arbitrarily normalized decay curve (ANDC) analyses being used for the 6s6p and 6p levels. In the case of the two 6s6p levels studied in Pb III, good agreement is found with a recent calculation in which a polarization model accounts for valence–core correlation. However, the agreement between the lifetimes observed for the 6p levels in Pb IV and a similar, earlier calculation is only fair.

SUPPORT FOR THE CHIRAL INTERPRETATION OF PARTNER BANDS IN 128Cs – THE ELECTROMAGNETIC PROPERTIES

2006 ◽  
Vol 15 (02) ◽  
pp. 548-552 ◽  
Author(s):  
E. GRODNER ◽  
J. SREBRNY ◽  
I. ZALEWSKA ◽  
T. MOREK ◽  
CH. DROSTE ◽  
...  
Keyword(s):  
Symmetry Breaking ◽  
Transition Probabilities ◽  
Theoretical Calculations ◽  
Chiral Symmetry Breaking ◽  
Coupling Model ◽  
Electromagnetic Properties ◽  
Lifetime Measurements ◽  
The Core ◽  
Reduced Transition Probabilities ◽  
Chiral Partner

Results of the DSAM lifetime measurements in supposed chiral partner bands of 128 Cs and 132 La are presented. Experimental reduced transition probabilities in 128 Cs are compared with theoretical calculations done in the frame of the Core-QuasiParticle Coupling model. The electromagnetic properties and energy pattern of partner bands show that 128 Cs is the best candidate revealing the chiral symmetry breaking phenomenon.

Beam-foil lifetime measurements for some 5d10nl and 5d96s6p levels of Pb IV

1991 ◽  
Vol 69 (5) ◽  
pp. 594-596 ◽  
Author(s):  
E. H. Pinnington ◽  
W. Ansbacher ◽  
A. Tauheed ◽  
J. A. Kernahan
Keyword(s):  
Decay Curve ◽  
Lifetime Measurements ◽  
Rigorous Calculation ◽  
Coulomb Approximation ◽  
Beam Foil ◽  
Foil Technique

The beam-foil technique was used to measure the lifetimes of the 5d105f, 5g, 6d, 6h, 7p, 7d, 8s and 5d96s6p [2]0, [3]0, [6]0, [14]0, [17]0 levels of Pb IV. Correlated decay-curve analyses were used to correct for the effects of cascading in the case of the 5d105f, 5g, 6d, and 7p levels. The numerical Coulomb approximation was used to calculate comparison values for the 5d10nl levels. The need for a more rigorous calculation for specific levels is discussed.

Lifetime measurements for low-lying levels in Hg I and Hg II using the beam-foil technique

1988 ◽  
Vol 66 (11) ◽  
pp. 960-962 ◽  
Author(s):  
E. H. Pinnington ◽  
W. Ansbacher ◽  
J. A. Kernahan ◽  
T. Ahmad ◽  
Z.-Q. Ge
Keyword(s):  
Energy Loss ◽  
Curve Fitting ◽  
Doppler Shift ◽  
Decay Curve ◽  
Carbon Foil ◽  
Lifetime Measurements ◽  
Resonance Transitions ◽  
Shift Technique ◽  
Beam Foil ◽  
Foil Technique

The techniques of beam-foil spectroscopy are applied to obtain measurements of the lifetimes of the 6s6p1P1, 3P1, 6s6d1D2, 3D1, 3D2, and 3D3 levels of Hg I and the 6p2P1/2, 2P3/2, 6d2D3/2, 2D5/2, and 7s2S1/2 levels of Hg II. The energy loss sustained by the ions in passing through the carbon foil is determined using an extended Doppler-shift technique. Constrained curve-fitting and arbitrarily normalized decay curve analyses are used to overcome problems caused by blending between transitions from the 6s6d1D2 and 3D1 levels of Hg I. The f values obtained from the resonance transitions are 1.14 ± 0.04 (Hg I) and 0.648 ± 0.022 (Hg II), in agreement with the trends found previously for higher Z ions in the Hg I and Au I isoelectronic sequences.

scholarly journals States Transitions Inference of Postpartum Depression Based on Multi-State Markov Model

2021 ◽  
Vol 18 (14) ◽  
pp. 7449
Author(s):  
Juan Xiong ◽  
Qiyu Fang ◽  
Jialing Chen ◽  
Yingxin Li ◽  
Huiyi Li ◽  
...  
Keyword(s):  
Postpartum Depression ◽  
Markov Model ◽  
Normal State ◽  
Sojourn Time ◽  
Transition Probabilities ◽  
Transition Probability ◽  
Public Health Problem ◽  
Mental States ◽  
Hazard Ratio ◽  
Multiple Time

Background: Postpartum depression (PPD) has been recognized as a severe public health problem worldwide due to its high incidence and the detrimental consequences not only for the mother but for the infant and the family. However, the pattern of natural transition trajectories of PPD has rarely been explored. Methods: In this research, a quantitative longitudinal study was conducted to explore the PPD progression process, providing information on the transition probability, hazard ratio, and the mean sojourn time in the three postnatal mental states, namely normal state, mild PPD, and severe PPD. The multi-state Markov model was built based on 912 depression status assessments in 304 Chinese primiparous women over multiple time points of six weeks postpartum, three months postpartum, and six months postpartum. Results: Among the 608 PPD status transitions from one visit to the next visit, 6.2% (38/608) showed deterioration of mental status from the level at the previous visit; while 40.0% (243/608) showed improvement at the next visit. A subject in normal state who does transition then has a probability of 49.8% of worsening to mild PPD, and 50.2% to severe PPD. A subject with mild PPD who does transition has a 20.0% chance of worsening to severe PPD. A subject with severe PPD is more likely to improve to mild PPD than developing to the normal state. On average, the sojourn time in the normal state, mild PPD, and severe PPD was 64.12, 6.29, and 9.37 weeks, respectively. Women in normal state had 6.0%, 8.5%, 8.7%, and 8.8% chances of progress to severe PPD within three months, nine months, one year, and three years, respectively. Increased all kinds of supports were associated with decreased risk of deterioration from normal state to severe PPD (hazard ratio, HR: 0.42–0.65); and increased informational supports, evaluation of support, and maternal age were associated with alleviation from severe PPD to normal state (HR: 1.46–2.27). Conclusions: The PPD state transition probabilities caused more attention and awareness about the regular PPD screening for postnatal women and the timely intervention for women with mild or severe PPD. The preventive actions on PPD should be conducted at the early stages, and three yearly; at least one yearly screening is strongly recommended. Emotional support, material support, informational support, and evaluation of support had significant positive associations with the prevention of PPD progression transitions. The derived transition probabilities and sojourn time can serve as an importance reference for health professionals to make proactive plans and target interventions for PPD.

Further enhancement on H∞ sliding mode control design for singular Markovian jump systems with partly known transition probabilities

2021 ◽  
pp. 107754632198920
Author(s):  
Zeinab Fallah ◽  
Mahdi Baradarannia ◽  
Hamed Kharrati ◽  
Farzad Hashemzadeh
Keyword(s):  
Transition Probabilities ◽  
Sliding Mode ◽  
Transition Probability ◽  
Transition Probability Matrix ◽  
Linear Matrix ◽  
Sliding Mode Controller ◽  
Sliding Surface ◽  
Markovian Jump ◽  
Markovian Jump System ◽  
Singular Markovian Jump Systems

This study considers the designing of the H ∞ sliding mode controller for a singular Markovian jump system described by discrete-time state-space realization. The system under investigation is subject to both matched and mismatched external disturbances, and the transition probability matrix of the underlying Markov chain is considered to be partly available. A new sufficient condition is developed in terms of linear matrix inequalities to determine the mode-dependent parameter of the proposed quasi-sliding surface such that the stochastic admissibility with a prescribed H ∞ performance of the sliding mode dynamics is guaranteed. Furthermore, the sliding mode controller is designed to assure that the state trajectories of the system will be driven onto the quasi-sliding surface and remain in there afterward. Finally, two numerical examples are given to illustrate the effectiveness of the proposed design algorithms.

Lifetime measurements of excited levels in C II and C III by beam-foil experiments

1996 ◽  
Vol 54 (2) ◽  
pp. 179-182 ◽  
Author(s):  
Tapan Nandi ◽  
Nandini Bhattacharya ◽  
M B Kurup ◽  
K G Prasad
Keyword(s):  
Lifetime Measurements ◽  
Beam Foil

scholarly journals Infinitely divisible random transition probabilities with application to dependent Markov chains

1984 ◽  
Vol 25 (4) ◽  
pp. 463-472
Author(s):  
Peter L. Chesson
Keyword(s):  
Markov Chain ◽  
Markov Chains ◽  
White Noise ◽  
Transition Probabilities ◽  
Transition Probability ◽  
Transition Rates ◽  
Infinitely Divisible ◽  
Random Transition ◽  
Transition Probability Matrices ◽  
Probability Matrices

AbstractRandom transition probability matrices with stationary independent factors define “white noise” environment processes for Markov chains. Two examples are considered in detail. Such environment processes can be used to construct several Markov chains which are dependent, have the same transition probabilities and are jointly a Markov chain. Transition rates for such processes are evaluated. These results have application to the study of animal movements.

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