Brühl R, Kalinin A, Kornilov O, Toennies J P, Hegerfeldt G C, Stoll M
Max-Planck-Institut für Dynamik und Selbstorganisation, Bunsenstrasse 10, 37073 Göttingen, Germany.
Phys Rev Lett. 2005 Aug 5;95(6):063002. doi: 10.1103/PhysRevLett.95.063002. Epub 2005 Aug 2.
The size of the helium trimer is determined by diffracting a beam of 4He clusters from a 100 nm period grating inclined by 21 degrees. Because of the bar thickness the projected slit width is roughly halved to 27 nm, increasing the sensitivity to the trimer size. The peak intensities measured out to the eighth order are evaluated via a few-body scattering theory. The trimer pair distance is found to be (r) = 1.1(+0.4)(-0.5) nm in agreement with predictions for the ground state. No evidence for a significant amount of Efimov trimers is found. Their concentration is estimated to be under 6%, less than expected.
通过使一束4He团簇从倾斜21度的100纳米周期光栅上衍射，来确定氦三聚体的大小。由于光栅条厚度的原因，投影狭缝宽度大致减半至27纳米，从而提高了对三聚体大小的敏感度。通过多体散射理论评估测量到的八阶峰值强度。发现三聚体对的距离为(r) = 1.1(+0.4)(-0.5)纳米，与基态的预测结果一致。未发现存在大量埃菲莫夫三聚体的证据。估计它们的浓度低于6%，低于预期。
