Comparison of positron-impact vibrational excitation cross sections with the Born-dipole model

✍ Scribed by J.P. Marler; G.F. Gribakin; C.M. Surko

• Book ID: 103861094
• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 371 KB
• Volume: 247
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2006.01.042

✦ Synopsis

The development of cold trap-based positron beams and new scattering techniques has recently enabled the first measurements of state-resolved positron-impact vibrational excitation cross sections. These measurements revealed a number of features worth further consideration, such as relatively sharp increases near threshold. This paper describes a comparison of the magnitudes and shapes of these cross sections with the predictions of the Born-dipole model. Agreement of the magnitudes of the cross sections varies widely, ranging from reasonable to excellent agreement for CO 2 and CF 4 to poor agreement for CO and CH 4 . In contrast, the energy dependence of these cross sections in all these cases is close to that predicted by the Born model.