In:
EPJ Web of Conferences, EDP Sciences, Vol. 212 ( 2019), p. 07002-
Kurzfassung:
A study of hadron production at the nucleon-antinucleon threshold has been performed with the CMD-3 detector at the VEPP-2000 e + e − collider. A very fast rise with an about 1 MeV width has been observed in the e + e − → pp ̅ cross section. A sharp drop in the e + e − → 3(π + π − ) cross section has been con?rmed and found to have a width of less than 2 MeV, in agreement with the observed fast rise of the e + e − → pp ̅ cross section. For the ?rst time a similar sharp drop is demonstrated in the e + e − → K + K − π + π − cross section. The behavior of the e + e − → 3(π + π − ), K + K − π + π − cross sections cannot be explained by an interference of any resonance amplitude with continuum, therefore this phenomenon cannot be due to a narrow near-threshold resonance. No such structure has been observed in the e + e − → 2(π + π − ) cross section.
Materialart:
Online-Ressource
ISSN:
2100-014X
DOI:
10.1051/epjconf/201921207002
Sprache:
Englisch
Verlag:
EDP Sciences
Publikationsdatum:
2019
ZDB Id:
2595425-8
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