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Related papers: Ultracold collisions of metastable helium atoms

200 papers

We review results on scattering observables for $^4$He--$^4$He$_2$ and $^3$He--$^4$He$_2$ collisions. We also study the effect of varying the coupling constant of the atom-atom interaction on the scattering length.

Atomic and Molecular Clusters · Physics 2007-07-17 Elena A. Kolganova , Alexander K. Motovilov , Werner Sandhas

Scattering and ionizing cross sections and rates are calculated for ultracold collisions between metastable helium atoms using a fully quantum-mechanical close-coupled formalism. Homonuclear collisions of the bosonic ${}^{4}$He$^{*}…

Atomic Physics · Physics 2019-07-03 D. G. Cocks , I. B. Whittingham , G. Peach

We report an experiment measuring simultaneously the temperatureand the flux of ions produced by a cloud of triplet metastablehelium atoms at the Bose-Einstein critical temperature. The onsetof condensation is revealed by a sharp increase…

We present results on the scattering lengths of ^4He--^4He_2 and ^3He--^4He_2 collisions. We also study the consequence of varying the coupling constant of the atom-atom interaction.

Atomic and Molecular Clusters · Physics 2007-05-23 Elena A. Kolganova , Alexander K. Motovilov , Werner Sandhas

We present a treatment of cold hydrogen-antihydrogen collisions based on the asymptotic properties of atom-antiatom interactions. We derive general formulas for the elastic and inelastic cross sections and for the scattering lengths and…

Atomic Physics · Physics 2009-11-13 A. Yu. Voronin , P. Froelich

We have obtained accurate ab initio quartet potentials for the diatomic metastable triplet helium + alkali-metal (Li, Na, K, Rb) systems, using all-electron restricted open-shell coupled cluster singles and doubles with noniterative triples…

Quantum Gases · Physics 2015-08-24 Dariusz Kȩdziera , Łukasz Mentel , Piotr S. Żuchowski , Steven Knoop

We present a new measurement of the s-wave scattering length a of spin-polarized helium atoms in the 2^3S_1 metastable state. Using two-photon photoassociation spectroscopy and dark resonances we measure the energy E_{v=14}= -91.35 +/- 0.06…

Other Condensed Matter · Physics 2009-11-11 S. Moal , M. Portier , J. Kim , J. Dugué , U. D. Rapol , M. Leduc , C. Cohen-Tannoudji

We have constructed the X 1SIGMAg+ potential for the collision between two ground state Mg atoms and analyzed the effect of uncertainties in the shape of the potential on scattering properties at ultra-cold temperatures. This potential…

Atomic Physics · Physics 2009-11-07 E. Tiesinga , S. Kotochigova , P. S. Julienne

The kinetic theory of evaporative cooling developed by Luiten et al. [Phys. Rev. A 53, 381 (1996)] is extended to include the dependence of the elastic scattering cross section on collision energy. We introduce a simple approximation by…

Soft Condensed Matter · Physics 2009-11-10 Paul J. J. Tol , W. Hogervorst , W. Vassen

We present our recent results on the scattering length of ^4He-^4He_2 collisions. These investigations are based on the hard-core version of the Faddeev differential equations. As compared to our previous calculations of the same quantity,…

Atomic and Molecular Clusters · Physics 2007-05-23 Elena A. Kolganova , Alexander K. Motovilov , Werner Sandhas

We observe light-induced frequency shifts in one-color photoassociative spectra of magnetically trapped $^4$He$^*$ atoms in the metastable $2^3S_1$ state. A pair of ultracold spin-polarized $2^3S_1$ helium atoms is excited into a molecular…

Atomic Physics · Physics 2009-11-11 J. Kim , S. Moal , M. Portier , J. Dugué , M. Leduc , C. Cohen-Tannoudji

We calculate the s-wave scattering length and effective range and the p-wave scattering volume for $^7$Li atoms interacting with $^{133}$Cs atoms via the X$^1\Sigma^+_g$ molecular potential. The length and volume are found by fitting the…

Atomic Physics · Physics 2015-04-07 M. J. Jamieson , H. Ouerdane

We show theoretically that ultracold hydrogen atoms have very favorable properties for sympathetic cooling of molecules to microkelvin temperatures. We calculate the potential energy surfaces for spin-polarized interactions of H atoms with…

Atomic Physics · Physics 2013-11-20 Maykel L. Gonzalez-Martinez , Jeremy M. Hutson

We consider two ultracold particles confined in spherically symmetric harmonic trap and interacting via isotropic potential with absorbing boundary conditions at short range that models reactive scattering. First, we apply the contact…

Quantum Physics · Physics 2016-06-01 Joanna Jankowska , Zbigniew Idziaszek

We have investigated the ultracold interspecies scattering properties of metastable triplet He and Rb. We performed state-of-the-art ab initio calculations of the relevant interaction potential, and measured the interspecies elastic cross…

We predict $s-$wave elastic cross-sections $\sigma$ for low-energy atom-molecule collisions with kinetic energies up to 40 mK, for the $^4$He collision with weakly bound diatomic molecules formed by $^4$He with $^7$Li, $^6$Li and $^{23}$Na.…

Atomic Physics · Physics 2018-09-26 M. A. Shalchi , A. Delfino , T. Frederico , Lauro Tomio

Ultracold atoms are increasingly used for high precision experiments that can be utilized to extract accurate scattering properties. This calls for a stronger need to improve on the accuracy of interatomic potentials, and in particular the…

Other Condensed Matter · Physics 2009-11-13 B. J. Verhaar , E. G. M. van Kempen , S. J. J. M. F. Kokkelmans

Polarizabilities, dispersion coefficients, and long-range atom-surface interaction potentials are calculated for the n=2 triplet and singlet states of helium using highly accurate, variationally determined, wave functions.

Atomic Physics · Physics 2007-05-23 Zong-Chao Yan , J. F. Babb

We analyze a system of two colliding ultracold atoms under strong harmonic confinement from the viewpoint of quantum defect theory and formulate a generalized self-consistent method for determining the allowed energies. We also present two…

Atomic Physics · Physics 2013-05-29 Gillian Peach , Ian B Whittingham , Timothy J Beams

Ultra-cold collisions of spin-polarized 24Mg,40Ca, and 88Sr in the metastable 3P2 excited state are investigated. We calculate the long-range interaction potentials and estimate the scattering length and the collisional loss rate as a…

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