Observation of psi (3686) -> n(n)over-bar and improved measurement of psi (3686) -> p(p)over-bar

BESIII Collaboration, Z. Haddadi, N. Kalantar-Nayestanaki, M. Kavatsyuk, H. Löhner, J. G. Messchendorp, M. Tiemens

OnderzoeksoutputAcademicpeer review

7 Citaten (Scopus)
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Samenvatting

We observe the decay psi (3686) -> n (n) over bar for the first time and measure psi (3686) -> p (p) over bar with improved accuracy by using 1.07 x 10(8) psi (3686) events collected with the BESIII detector. The measured branching fractions are B(psi(3686) -> n (n) over bar) = (3.06 +/- 0.06 +/- 0.14) x 10(-4) and B(psi(3686) -> p (p) over bar) = (3.05 +/- 0.02 +/- 0.12) x 10(-4). Here, the first uncertainties are statistical, and the second ones are systematic. With the hypothesis that the polar angular distributions of the neutron and proton in the center-of-mass system obey 1 + alpha cos(2) theta, we determine the a parameters to be alpha(n (n) over bar) = 0.68 +/- 0.12 +/- 0.11 and alpha(p (p) over bar) = 1.03 +/- 0.06 +/- 0.03 for psi(3686) -> n (n) over bar and psi(3686) -> p (p) over bar, respectively.
Originele taal-2English
Artikelnummer032006
Aantal pagina's13
TijdschriftPhysical Review D
Volume98
Nummer van het tijdschrift3
DOI's
StatusPublished - 10-aug-2018

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