ترغب بنشر مسار تعليمي؟ اضغط هنا

Three-potential formalism for the atomic three-body problem

302   0   0.0 ( 0 )
 نشر من قبل Papp Zoltan
 تاريخ النشر 1997
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Z. Papp




اسأل ChatGPT حول البحث

Based on a three-potential formalism we propose mathematically well-behaved Faddeev-type integral equations for the atomic three-body problem and descibe their solutions in Coulomb-Sturmian space representation. Although the system contains only long-range Coulomb interactions these equations allow us to reach solution by approximating only some auxiliary short-range type potentials. We outline the method for bound states and demonstrate its power in benchmark calculations. We can report a fast convergence in angular momentum channels.



قيم البحث

اقرأ أيضاً

A three-body scattering process in the presence of Coulomb interaction can be decomposed formally into a two-body single channel, a two-body multichannel and a genuine three-body scattering. The corresponding integral equations are coupled Lippmann-S chwinger and Faddeev-Merkuriev integral equations. We solve them by applying the Coulomb-Sturmian separable expansion method. We present elastic scattering and reaction cross sections of the $e^++H$ system both below and above the $H(n=2)$ threshold. We found excellent agreements with previous calculations in most cases.
103 - Z. Papp 1997
We propose a three-potential formalism for the three-body Coulomb scattering problem. The corresponding integral equations are mathematically well-behaved and can succesfully be solved by the Coulomb-Sturmian separable expansion method. The results s how perfect agreements with existing low-energy $n-d$ and $p-d$ scattering calculations.
110 - S Keller , A Marotta , Z Papp 2008
Three-body resonances in atomic systems are calculated as complex-energy solutions of Faddeev-type integral equations. The homogeneous Faddeev-Merkuriev integral equations are solved by approximating the potential terms in a Coulomb-Sturmian basis. T he Coulomb-Sturmian matrix elements of the three-body Coulomb Greens operator has been calculated as a contour integral of two-body Coulomb Greens matrices. This approximation casts the integral equation into a matrix equation and the complex energies are located as the complex zeros of the Fredholm determinant. We calculated resonances of the e-Ps system at higher energies and for total angular momentum L=1 with natural and unnatural parity
Although the convergent close-coupling (CCC) method has achieved unprecedented success in obtaining accurate theoretical cross sections for electron-atom scattering, it generally fails to yield converged energy distributions for ionization. Here we r eport converged energy distributions for ionization of H(1s) by numerically integrating Schroedingers equation subject to correct asymptotic boundary conditions for the Temkin-Poet model collision problem, which neglects angular momentum. Moreover, since the present method is complete, we obtained convergence for all transitions in a single calculation. Complete results, accurate to 1%, are presented for impact energies of 54.4 and 40.8 eV, where CCC results are available for comparison.
171 - T.C. Luu , S. Bogner , W.C. Haxton 2004
The three-body energy-dependent effective interaction given by the Bloch-Horowitz (BH) equation is evaluated for various shell-model oscillator spaces. The results are applied to the test case of the three-body problem (triton and He3), where it is s hown that the interaction reproduces the exact binding energy, regardless of the parameterization (number of oscillator quanta or value of the oscillator parameter b) of the low-energy included space. We demonstrate a non-perturbative technique for summing the excluded-space three-body ladder diagrams, but also show that accurate results can be obtained perturbatively by iterating the two-body ladders. We examine the evolution of the effective two-body and induced three-body terms as b and the size of the included space Lambda are varied, including the case of a single included shell, Lambda hw=0 hw. For typical ranges of b, the induced effective three-body interaction, essential for giving the exact three-body binding, is found to contribute ~10% to the binding energy.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا