Search results for "wave function"
showing 10 items of 395 documents
Static properties and semileptonic decays of doubly heavy baryons in a nonrelativistic quark model
2006
We evaluate static properties and semileptonic decays for the ground state of doubly heavy $\Xi, \Xi', \Xi^*$ and $\Omega, \Omega', \Omega^*$ baryons. Working in the framework of a nonrelativistic quark model, we solve the three--body problem by means of a variational ansazt made possible by heavy quark spin symmetry constraints. To check the dependence of our results on the inter-quark interaction we use five different quark-quark potentials that include a confining term plus Coulomb and hyperfine terms coming from one--gluon exchange. Our results for static properties (masses, charge and mass radii, magnetic moments...) are, with a few exceptions for the magnetic moments, in good agreemen…
Color-singlet states in a hadronic quark-cluster basis
1987
We prove that any physical (color-singlet) state can be expanded in terms of a basis constructed by direct product from baryonic and/or mesonic states. The proof is based on a group-theoretical representation method due to Hund. The application of the procedure to the color degrees of freedom leads to known results, which we generalize to more complex situations. The joint application of the method to the color and flavor degrees of freedom results in our initial statement. In this way one is able to give physical meaning to a mathematical procedure. The physics behind our calculation is intimately connected with the concepts of elementarity of constituents and the spinstatistics theorem. T…
Scattering of Particles by Potentials
2013
The three prototypes of spectra of self-adjoint operators, the discrete spectrum, with or without degeneracy, the continuous spectrum, and the mixed spectrum, as well as the corresponding wave functions, contain important information about the physical systems that they describe
Solution of the fully-mixed-state problem: Direct deperturbation analysis of theAΣ+1–bΠ3complex in a NaCs dimer
2009
Laser-induced fluorescence (LIF) spectra $(4)\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}\ensuremath{\rightarrow}A\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}--b\phantom{\rule{0.2em}{0ex}}^{3}\ensuremath{\Pi}$ and collisionally enhanced $A\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}--b\phantom{\rule{0.2em}{0ex}}^{3}\ensuremath{\Pi}\ensuremath{\rightarrow}X\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}$ LIF spectra measured by Fourier transform spectrometer with the resolution of $0.03--0.05\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ provided about 1160 term values of the $e$-symmetry rovibronic levels of the fully mixed $A\phantom{\rule{…
Scaling violation in the infinite-momentum frame
1978
The theory of scaling violation is studied in asymptotically free gauge theories formulated in the infinite-momentum frame. The transition probabilities occurring in the equation governing the q/sup 2/ dependence of the parton distributions are calculated directly. The equivalence of this formalism for the longitudinal parton distributions with the usual one based on the operator-product expansion is demonstrated. The assets of our method are calculational simplicity and reference to physical intuition.
Definition of an appropriate free dynamics and the physical S-matrix in multichannel hyperradial adiabatic scattering
2010
In the hyperradial adiabatic (HA) treatment of the three-body problem the total wave function is i expanded as ΨHA(R, ξ, η) = R−5/2 ∑iχi(R)φi(R|ξ, η),where R denotes the hyperradius and (ξ , η) are internal hyperangles. Integration over ξ and η converts the Schrödinger equation into a system of coupled hyperradial equations. It is a well-known fact that, within the HA approach, the non-adiabatic corrections that couple channels converging to the same asymptotic configuration can show an unphysical long-range behavior ∼ 1/R. Though the latter is of purely kinematic origin and arises from the use of the hyperradius instead of the pertinent Jacobi variables, it is nevertheless the source of the…
Pion Scattering and Pion Photoproduction on 3He
1992
Using realistic 3-body Faddeev wave functions π± scattering and π+ photoproduction on 3He have been calculated in a consistent model. We demonstrate that at T π ≤ 180MeV polarization observables in pion scattering contain very little information about nuclear structure and can be understood in terms of free πN amplitudes. At higher energies the sign-flip of the asymmetry A y offers a new possibility to study higher-order effects of pion nuclear interaction. In pion photoproduction we find that two-step processes such as 3 He(γ, π°)3 He(π°, π+)3 H give rise to unexpected large contributions to the differential crosssection as well as to γ-asymmetry and with this improved a long time discrepa…
Sign problem of the fermionic shadow wave function
2014
We present a whole series of methods to alleviate the sign problem of the fermionic shadow wave function in the context of variational Monte Carlo. The effectiveness of our techniques is demonstrated on liquid ^{3}He. We found that although the variance is reduced, the gain in efficiency is restricted by the increased computational cost. Yet, this development not only extends the scope of the fermionic shadow wave function, but also facilitates highly accurate quantum Monte Carlo simulations previously thought not feasible.
Laser driven structured quantum rings
2015
In this work we study harmonic emission from structured quantum rings (SQRs). In SQRs, electrons trapped in two-dimensional structures are further confined by an external potential composed of N scattering centers arranged on a circle. We build a suitable one-dimensional model Hamiltonian describing this class of systems and analytically solve the associated Schödinger equation. We find that the solution can be expressed in terms of Mathieu functions and focus on the specific case of N = 6. By exactly solving the time-dependent Schödinger equation, we then show how the harmonic response to linearly polarized lasers strongly depends on the ring physical parameters. The results illustrate how…
Minimal Model of Spin-Transfer Torque and Spin Pumping Caused by the Spin Hall Effect
2015
In the normal metal/ferromagnetic insulator bilayer (such as Pt/Y$_{3}$Fe$_{5}$O$_{12}$) and the normal metal/ferromagnetic metal/oxide trilayer (such as Pt/Co/AlO$_{x}$) where spin injection and ejection are achieved by the spin Hall effect in the normal metal, we propose a minimal model based on quantum tunneling of spins to explain the spin-transfer torque and spin pumping caused by the spin Hall effect. The ratio of their damping-like to field-like component depends on the tunneling wave function that is strongly influenced by generic material properties such as interface $s-d$ coupling, insulating gap, and layer thickness, yet the spin relaxation plays a minor role. The quantified resu…