scholarly journals Is two-pole’s $$\varLambda (1405)$$ one state or two?

2021 ◽  
Vol 81 (9) ◽  
Author(s):  
Zhong-Yu Wang ◽  
Hiwa A. Ahmed ◽  
C. W. Xiao

AbstractTo understand the nature of two poles for the $$\varLambda (1405)$$ Λ ( 1405 ) state, we revisit the interactions of $${\bar{K}}N$$ K ¯ N and $$\pi \Sigma $$ π Σ with their coupled channels, where two-pole structure is found in the second Riemann sheet. We also dynamically generate two poles in the single channel interaction of $${\bar{K}}N$$ K ¯ N and $$\pi \Sigma $$ π Σ , respectively. Moreover, we make a further study of two poles’ properties by evaluating the couplings, the compositeness, the wave functions, and the radii for the interactions of four coupled channels, two coupled channels and the single channel. Our results show that the nature of two poles is unique. The higher-mass pole is a pure $${\bar{K}} N$$ K ¯ N molecule, and the lower-mass one is a composite state of mainly $$\pi \Sigma $$ π Σ with tiny component $${\bar{K}} N$$ K ¯ N . From our results, one can conclude that the $$\varLambda (1405)$$ Λ ( 1405 ) state may be overlapped with two different states of the same quantum numbers.

Author(s):  
Frank S. Levin

The subject of Chapter 8 is the fundamental principles of quantum theory, the abstract extension of quantum mechanics. Two of the entities explored are kets and operators, with kets being representations of quantum states as well as a source of wave functions. The quantum box and quantum spin kets are specified, as are the quantum numbers that identify them. Operators are introduced and defined in part as the symbolic representations of observable quantities such as position, momentum and quantum spin. Eigenvalues and eigenkets are defined and discussed, with the former identified as the possible outcomes of a measurement. Bras, the counterpart to kets, are introduced as the means of forming probability amplitudes from kets. Products of operators are examined, as is their role underpinning Heisenberg’s Uncertainty Principle. A variety of symbol manipulations are presented. How measurements are believed to collapse linear superpositions to one term of the sum is explored.


2019 ◽  
Vol 79 (12) ◽  
Author(s):  
Qi-Xin Yu ◽  
J. M. Dias ◽  
Wei-Hong Liang ◽  
E. Oset

AbstractWe have studied the meson–baryon interaction in coupled channels with the same quantum numbers of $$\Xi _{bc}$$Ξbc. The interaction is attractive in some channels and of sufficient intensity to lead to bound states or resonances. We use a model describing the meson–baryon interaction based on an extrapolation of the local hidden gauge approach to the heavy sector, which has been successfully used in predicting $$\Omega _c$$Ωc and hidden charm states. We obtain many states, some of them narrow or with zero width, as a consequence of the interaction, which qualify as molecular states in those channels. The success in related sectors of the picture used should encourage the experimental search for such states.


1991 ◽  
Vol 260 (5) ◽  
pp. E772-E779 ◽  
Author(s):  
U. Brauneis ◽  
P. M. Vassilev ◽  
S. J. Quinn ◽  
G. H. Williams ◽  
D. L. Tillotson

Angiotensin II (ANG II) is a principal secretagogue of adrenal zona glomerulosa (ZG) cells. The transduction process includes a depolarization of the plasma membrane and the activation of calcium influx. The ANG II-induced depolarization is associated with an increase in total membrane resistance. To directly address the mechanism underlying these observations, we examined the effect of ANG II on K+ currents of rat, bovine, and human ZG cells, using whole cell patch clamp. Although some differences were seen in the characteristics of K+ currents between species, ANG II consistently blocked outward currents in ZG cells [rat: 47.1 +/- 4.5% (SE), n = 17; bovine: 38.6 +/- 3.3%, n = 21; and human: 13-63%, n = 3]. With the use of the cell-attached mode, single-channel recordings in bovine ZG cells demonstrated K+ channels that were reversibly blocked when ANG II was added to the bath solution. This indicates that the block of K+ channels by ANG II involves a diffusible intracellular messenger rather than a direct receptor-channel interaction. The decreased conductance of K+ can account for the ANG II-induced membrane depolarization.


1981 ◽  
Vol 36 (12) ◽  
pp. 1327-1333
Author(s):  
F. Scappini ◽  
H. Dreizler

AbstractThe microwave ground state spectrum of cis propionyl fluoride has been investigated expanding, with respect to a previous study, the range of the quantum numbers of the transitions, J up to 40 and K up to 18. At low K the spectrum resembles that of an asymmetric rigid rotor, except in a number of cases where the lines are split into A, E doublets. At intermediate and high K the mixing of the if-doublet rigid rotor wave functions makes forbidden transitions appear. The results of the analysis of the methyl top internal rotation ground state splittings are: V3 = 2350 ± 11 cal/mole, ≮ (i, a) = 32.7° ±2.0°, and Iα = 3.18 ± 0.03 uÅ2.


2015 ◽  
Vol 24 (11) ◽  
pp. 1550081 ◽  
Author(s):  
Yong-Jing Chen ◽  
Yong-Shou Chen ◽  
Zao-Chun Gao ◽  
Ya Tu

Based on existence of the octupole deformation in the intrinsic states, the experimentally observed four rotational bands in [Formula: see text]Ba have been well reproduced by the reflection asymmetric shell model (RASM) calculations. Through the analysis of the calculated RASM wave functions, the intrinsic configuration of the observed rotational bands has been assigned as the octupole deformed neutron [Formula: see text] orbit, which is just located below the [Formula: see text] shell gap. The calculated results supported the ground state octupole deformation and the purity of the simplex quantum numbers [Formula: see text] in [Formula: see text]Ba. In addition, the calculated [Formula: see text] values are in agreement with experimental data, and further support the octupole deformation in [Formula: see text]Ba.


2016 ◽  
Vol 25 (01) ◽  
pp. 1650002 ◽  
Author(s):  
V. H. Badalov

In this work, the analytical solutions of the [Formula: see text]-dimensional radial Schrödinger equation are studied in great detail for the Wood–Saxon potential by taking advantage of the Pekeris approximation. Within a novel improved scheme to surmount centrifugal term, the energy eigenvalues and corresponding radial wave functions are found for any angular momentum case within the context of the Nikiforov–Uvarov (NU) and Supersymmetric quantum mechanics (SUSYQM) methods. In this way, based on these methods, the same expressions are obtained for the energy eigenvalues, and the expression of radial wave functions transformed each other is demonstrated. In addition, a finite number energy spectrum depending on the depth of the potential [Formula: see text], the radial [Formula: see text] and orbital [Formula: see text] quantum numbers and parameters [Formula: see text] are defined as well.


2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Levent Yilmaz

Meander flow takes place in one single channel which oscillates more orless regularly with amplitudes that tend to increase with time. Meandersare found in beds of fine sediments with gentle slopes. In this study, effortwill be made to investigate meanders’ turbulent boundary layer and toimprove the present knowledge about the river meandering phenomena. Itis assumed that the development of the perturbations which develop intomeanders or braids, is longer than the width of the channel. Interaction between the flow and mobile boundaries produces channel patterns which areclassified as meandering or braided. It is therefore long compared with theripples or dunes which cover the bed of such a channel and whose wavelength is shorter than the width of the channel. The variation of resistance toflow and rate of transport of bed material with velocity are discussed brieflyand taken into account. Meander flow and meander shear stress distribution of the channel are described. The basis is a steady, two-dimensionalmodel of flow in an alluvial channel with variable curvature. The meanderdevelopment is described by forcing a travelling, small-amplitude channelalignment wave on the system, and determining the growth characteristicsof the wave. Laboratory data are used to verify the formulas.


2018 ◽  
Vol 175 ◽  
pp. 05013 ◽  
Author(s):  
Noriyoshi Ishii ◽  
Sinya Aoki ◽  
Takumi Doi ◽  
Shinya Gongyo ◽  
Tetsuo Hatsuda ◽  
...  

Hyperon-nucleon and hyperon-hyperon interactions are important in studying the properties of hypernuclei in hypernuclear physics. However, unlike the nucleons which are quite stable, hyperons are unstable so that the direct scattering experiments are difficult, which leads to the large uncertainty in the phenomenological determination of hyperon potentials. In this talk, we use the gauge configurations generated at the (almost) physical point (mπ = 146 MeV) on a huge spatial volume (8:1fm)4 to present our latest result on the hyperon-hyperon potentials in S = −3 sector (Ξ∑ single channel and Ξ∑- ΞΛ; coupled channel) from the Nambu-Bethe-Salpeter wave functions based on the HAL QCD method with improved statistics.


Open Physics ◽  
2005 ◽  
Vol 3 (3) ◽  
Author(s):  
Spyros Themelis

AbstractHigh-lying doubly excited states of He and H− are studied and energies and intrinsic characteristics of their wave-functions are reported. Results for energies of 3Po and 1D doubly excited states associated with the hydrogenic thresholds up to N = 20 are presented and compared to available data from the literature. The classification of these doubly excited states by approximate quantum numbers is reexamined.


The wave functions for a number of particles in a degenerate oscillator level, classified in part I according to irreducible representations of the group U 3 , are expressed as integrals of the Hill-Wheeler type over intrinsic states. The rotational band structure which appeared in the classification is now understood, since all states of a band are shown to involve the same intrinsic state in the integral. It is possible to use the quantum number K of the intrinsic states as an additional label for the final wave functions, thus distinguishing states which, in the classification of part I, had the same values for all other quantum numbers used. The integral form for the wave functions enables simple expressions to be obtained for the quadrupole moments which resemble those of the rotational model for a permanent deformation.


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