scholarly journals Calculation of the annihilation rate of P wave quark-antiquark bound states

1976 ◽  
Vol 60 (2) ◽  
pp. 183-188 ◽  
Author(s):  
R. Barbieri ◽  
R. Gatto ◽  
R. Kögerler
Keyword(s):  
Bound States ◽  
P Wave ◽  
Annihilation Rate

Spectroscopy of heavy quark hadrons

2014 ◽  
Vol 23 (07) ◽  
pp. 1461007
Author(s):  
Makoto Oka
Keyword(s):  
Heavy Quark ◽  
Bound States ◽  
Heavy Quarks ◽  
P Wave ◽  
Charmed Baryon ◽  
Hadron Spectroscopy ◽  
Distinct Features

Heavy quarks play special roles in the hadron spectroscopy. Some distinct features of heavy quark dynamics and their significance in the P-wave baryons with a single heavy quark are discussed. We also explore a new color configuration in exotic tetra-quark mesons with two heavy quarks. Finally, possibility of bound states of a charmed baryon with a nucleon and nuclei are examined.

A SELF-CONSISTENT ANALYTIC THEORY OF THE SPIN BIPOLARON IN THE t–J MODEL

2000 ◽  
Vol 14 (08) ◽  
pp. 809-835
Author(s):  
HEINZ BARENTZEN ◽  
VIKTOR OUDOVENKO
Keyword(s):  
Integral Equation ◽  
Eigenvalue Problem ◽  
Bound States ◽  
Numerical Solutions ◽  
P Wave ◽  
Linear Integral Equation ◽  
Soluble Form ◽  
Coupled Equations ◽  
Self Consistent ◽  
D Wave

The spin bipolaron in the t–J model, i.e., two holes interacting with an antiferromagnetic spin background, is treated by an extension of the self-consistent Born approximation (SCBA), which has proved to be very accurate in the single-hole (spin polaron) problem. One of the main ingredients of our approach is the exact form of the bipolaron eigenstates in terms of a complete set of two-hole basis vectors. This enables us to eliminate the hole operators and to obtain the eigenvalue problem solely in terms of the boson (magnon) operators. The eigenvalue equation is then solved by a procedure similar to Reiter's construction of the single-polaron wave function in the SCBA. As in the latter case, the eigenvalue problem comprises a hierarchy of infinitely many coupled equations. These are brought into a soluble form by means of the SCBA and an additional decoupling approximation, whereupon the eigenvalue problem reduces to a linear integral equation involving the bipolaron self-energy. The numerical solutions of the integral equation are in quantitative agreement with the results of previous numerical studies of the problem. The d-wave bound state is found to have the lowest energy with a critical value J/t| c ≈ 0.4. In contrast to recent claims, we find no indication for a crossover between the d-wave and p-wave bound states.

scholarly journals Positron annihilation rate in single atom with slater type orbital approximation

2013 ◽  
Vol 16 (4) ◽  
pp. 43-51
Author(s):  
Lang Hoang Trinh ◽  
Tao Van Chau ◽  
Chien Hoang Le ◽  
Hong Thi Yen Huynh ◽  
Tram Ngoc Huynh
Keyword(s):  
Positron Annihilation ◽  
Bound States ◽  
Pair Correlation ◽  
Analytical Form ◽  
Single Atom ◽  
Annihilation Rate ◽  
Slater Type ◽  
Slater Type Orbital ◽  
Type Orbital ◽  
Orbital Approximation

A theoretical approximation for the structure of many-positron and manyelectron atoms in bound states is presented. The purpose of this theory is to permit the calculation of positron lifetimes from annihilation enhancement factor which is directly estimated by pair correlation function for each element atom, but not analytical form of correlation functions which depend upon homogeneous electron gas Monte– Carlo simulation data. We therefore used a modified orbital approximation for the electrons and positron. The orbital modification consisting of explicit electronpositron and electron-electron correlation in each elec-tronic orbital was used for the electrons and positron wave functions. The kinetic energies of the electrons and positron were treated on the same footing, and the Born-Oppenheimer approximation was applied to the nuclei. In this paper we treated only those systems for the valance electrons in the real spatial coordinate of the atom or molecule. The complex of many-particle problem was solved by the Schrongdinger of one particle equation which is derived by Kohn–Sham approximation and single particle wave function of Slater type orbital. As a result of this model, the positron annihilation rate and lifetime in some atoms, Ti, Zn and Zr, were calculated.

Including the strong nuclear force in antihydrogen-scattering calculations

2005 ◽  
Vol 83 (4) ◽  
pp. 435-445 ◽  
Author(s):  
S Jonsell ◽  
A Saenz ◽  
P Froelich ◽  
B Zygelman ◽  
A Dalgarno
Keyword(s):  
Cross Sections ◽  
Strong Interaction ◽  
Ground State ◽  
Wave Scattering ◽  
Bound States ◽  
Nuclear Force ◽  
Scattering Length ◽  
Finite Size ◽  
P Wave ◽  
Atomic Unit

We investigate two methods to include the strong nuclear force in hydrogen–antihydrogen scattering calculations. First, we construct a model optical potential with parameters determined by the measured shift and width of the protonium ground state. Although this potential is a very crude model for the strong nuclear force, its parameters may be adjusted to reproduce both bound states and low-energy annihilation cross sections to within the experimental accuracy. It is then shown that this potential may be reduced to a short-distance boundary condition in terms of the proton–antiproton strong-interaction scattering length. Elastic and annihilation cross sections for ground-state hydrogen–antihydrogen scattering are calculated for s- and p-waves, and collision energies up to 1 atomic unit. The two methods are found to agree to within about 1%. The main source of discrepancy is that the scattering-length approach does not account for vacuum polarization, relativistic, and finite-size corrections. We verify that the range of the strong interaction potential does not affect the hydrogen–antihydrogen s-wave scattering properties, and that the strong interaction has negligible influence on p-wave scattering. PACS Nos.: 36.10.-k, 34.90.+q

Suppressed Andreev reflection and helical Andreev bound states in triplet superconductor three-dimensional topological insulator

2015 ◽  
Vol 29 (04) ◽  
pp. 1550018 ◽  
Author(s):  
M. Khezerlou ◽  
H. Goudarzi
Keyword(s):  
Topological Insulator ◽  
Bound States ◽  
Andreev Reflection ◽  
Chemical Potential ◽  
Three Dimensional ◽  
P Wave ◽  
Superconducting Gap ◽  
Tunneling Conductance ◽  
Andreev Bound States ◽  
Josephson Supercurrent

Effect of proximity-induced unconventional p-wave superconductivity in a three-dimensional topological insulator-based S/F/S structure on the Andreev bound states (ABSs) and Josephson supercurrent is studied. We investigate, in detail, the suppression of Andreev reflection and helical ABSs in the presence of three types of triplet superconducting gap. The magnetization of ferromagnetic section is perpendicular to the surface of junction. The influence of such features on the supercurrent flow on the surface of the topological insulator is studied. We carry out our goal by introducing a relevant form of Dirac spinors for gapless renormalized by chemical potential μ excitation states. Therefore, it enables us to consider the virtual Andreev process, simultaneously, and we propose to investigate it in a tunneling conductance junction. It is shown that the results obtained in this case are completely different from those in conventional superconductivity, as s- or d-waves, for example, the magnetization is found to decrease the gap for px and px+ipy case, whereas increase it for py order. Strongly suppressed Andreev reflection is demonstrated.

Investigation of Resonances in the Scattering of a Heavy ‘Positron’ by H2 that Involve Vibrationally Excited Quasi-Bound States

2010 ◽  
Vol 666 ◽  
pp. 25-30
Author(s):  
Edward A.G. Armour
Keyword(s):  
Variational Method ◽  
Bound States ◽  
Low Energy ◽  
Annihilation Rate ◽  
Effective Number ◽  
Feshbach Resonances ◽  
Vibrational States ◽  
Vibrationally Excited ◽  
Positron Scattering ◽  
Very High

There is currently great interest in the very large values of the positron annihilation rate that have been observed in low-energy positron scattering by some molecules. The annihilation rate is proportional to , the effective number of electrons in the target available to the positron for annihilation. These very high rates and associated values of have been observed experimentally to occur at energies just below the energies of excited vibrational states of the molecule concerned. This has been explained by Gribakin [Phys. Rev. A Vol. 61 (2000), p. 022720] and Gribakin and Lee [Phys. Rev. Lett. Vol. 97 (2006), p. 193201] as being due to Feshbach resonances involving excited quasi-bound vibrational states. Their explanation is partly phenomenological. In this paper, I describe the results of an ab initio treatment of this resonant behaviour in the case of the scattering of a heavy ‘positron’ by , using the Kohn variational method.

scholarly journals Skyrmion-induced bound states in a p -wave superconductor

2016 ◽  
Vol 94 (21) ◽  
Author(s):  
Kim Pöyhönen ◽  
Alex Westström ◽  
Sergey S. Pershoguba ◽  
Teemu Ojanen ◽  
Alexander V. Balatsky
Keyword(s):  
Bound States ◽  
P Wave

scholarly journals Chiral singlet superconductivity in the weakly correlated metal LaPt3P

2020 ◽  
Author(s):  
Pabitra Biswas ◽  
Sudeep Ghosh ◽  
Jianzhou Zhao ◽  
Daniel Mayoh ◽  
Nikolai Zhigadlo ◽  
...  
Keyword(s):  
Bound States ◽  
Fault Tolerant ◽  
Muon Spin ◽  
Mean Field Theory ◽  
Mean Field ◽  
P Wave ◽  
Band Structure Calculation ◽  
Linear Behaviour ◽  
Triplet Pairing ◽  
Breaking Time

Abstract Topological superconductors (SCs) are novel phases of matter with nontrivial bulk topology. They host at their boundaries and vortex cores zero-energy Majorana bound states, potentially useful in fault-tolerant quantum computation [1]. Chiral SCs [2] are particular examples of topological SCs with finite angular momentum Cooper pairs circulating around a unique chiral axis, thus spontaneously breaking time-reversal symmetry (TRS). They are rather scarce and usually feature triplet pairing: best studied examples in bulk materials are UPt<3> and Sr<2>RuO<4> proposed to be f-wave and p-wave SCs respectively, although many open questions still remain [2]. Chiral triplet SCs are, however, topologically fragile with the gapless Majorana modes weakly protected against symmetry preserving perturbations in contrast to chiral singlet SCs [3, 4]. Using muon spin relaxation (μSR) measurements, here we report that the weakly correlated pnictide compound LaPt<3>P has the two key features of a chiral SC: spontaneous magnetic fields inside the superconducting state indicating broken TRS and low-temperature linear behaviour in the superfluid density indicating line nodes in the order parameter. Using symmetry analysis, first principles band structure calculation and mean-field theory, we unambiguously establish that the superconducting ground state of LaPt<3>P is chiral d-wave singlet.

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