Study of $J/{\psi}{\rightarrow}p\bar{p}$ and $J/{\psi}{\rightarrow}n\bar{n}$

Loading...
Thumbnail Image
Can’t use the file because of accessibility barriers? Contact us with the title of the item, permanent link, and specifics of your accommodation need.

Date

2012

Journal Title

Journal ISSN

Volume Title

Publisher

American Physical Society

Abstract

The decays $J/{\psi}{\rightarrow}p\bar{p}$ and $J/{\psi}{\rightarrow}n\bar{n}$ have been investigated with a sample of $225.2×10^6$ $J/{\psi}$ events collected with the BESIII detector at the BEPCII $e^+e^-$ collider. The branching fractions are determined to be $\mathscr{B}(J/{\psi}{\rightarrow}p\bar{p})=(2.112±0. 004±0.031)×10^{-3}$ and $\mathscr{B}(J/{\psi}{\rightarrow}n\bar{n})=(2.07±0.01±0.17)×10^{-3}$. Distributions of the angle $\theta$ between the proton or antineutron and the beam direction are well described by the form $1+\alpha cos2\theta$, and we find $\theta=0.595±0.012±0.015$ for $J/{\psi}{\rightarrow}p\bar{p}$ and $\theta=0.50±0.04±0.21$ for $J/{\psi}{\rightarrow}n\bar{n}$. Our branching-fraction results suggest a large phase angle between the strong and electromagnetic amplitudes describing the $J/{\psi}{\rightarrow}N\bar{N}$ decay.

Description

Keywords

Citation

Ablikim, M., Achasov, M. N., Ambrose, D. J., An, F. F., An, Q., An, Z. H., . . . Zuo, J. X. (2012). Study of $J/{\psi}{\rightarrow}p\bar{p}$ and $J/{\psi}{\rightarrow}n\bar{n}$. Physical Review D - Particles, Fields, Gravitation and Cosmology, 86(3), 032014. http://dx.doi.org/10.1103/PhysRevD.86.032014

Journal

DOI

Link(s) to data and video for this item

Relation

Rights

© 2012 American Physical Society.

Type

Article