|
|||||
|
|
Excitation of the Roper resonance in single- and double-pion production in nucleon-nucleon collisions? |
|
| Authors: | T Skorodko M Bashkanov D Bogoslawsky H Calen F Cappellaro H Clement L Demiroers E Doroshkevich D Duniec C Ekström K Franssen L Gustafsson B Höistad G Ivanov M Jacewicz E Jiganov T Johansson O Khakimova M Kaskulov S Keleta I Koch F Kren S Kullander A Kup?? A Kuznetsov P Marciniewski R Meier B Morosov C Pauly H Petterson Y Petukhov A Povtorejko K Schönning W Scobel B Shwartz V Sopov J Stepeniak P Thörngren-Engblom V Tikhomirov G J Wagner M Wolke A Yamamoto J Zabierowski J Z?omanczuk |
| Institution: | 1. Physikalisches Institut der Universit?t Tübingen, Auf der Morgenstelle 14, D-72076, Tübingen, Germany 2. Joint Institute for Nuclear Research, Dubna, Russia 3. The Svedberg Laboratory, Uppsala, Sweden 4. Uppsala University, Uppsala, Sweden 5. Hamburg University, Hamburg, Germany 6. Budker Institute of Nuclear Physics, Novosibirsk, Russia 7. Institute of Theoretical and Experimental Physics, Moscow, Russia 8. Soltan Institute of Nuclear Studies, Warsaw, Poland 9. Forschungszentrum Jülich, Germany 10. High Energy Accelerator Research Organization, Tsukuba, Japan 11. Soltan Institute of Nuclear Studies, Lodz, Poland |
| Abstract: | In most investigations the Roper resonance is sensed only very indirectly via complex partial-wave analyses. We find indications for its excitation in the invariant nπ+ mass spectrum of the pp → npπ+ reaction at M ≈ 1360 MeV with a width of ≈ 150 MeV . The values fit very favorably to the most recent phase shift results as well as to the observations at BES. In the near-threshold two-pion production pp → ppπ0π0 , where the Roper excitation and its subsequent decays via the routes N * → Δπ → Nππ and N * → Nσ are the only dominant processes, we find its direct decay into the Nσ channel to be the by far dominating decay process --in favor of a monopole excitation of the Roper resonance. |
| Keywords: | 13 75 Cs Nucleon-nucleon interactions (including antinucleons deuterons etc ) 14 20 Gk Baryon resonances with S = 0 |
| 本文献已被 SpringerLink 等数据库收录！ | |