摘要
当J/φ辐射衰变产物X是两个赝标介子的束缚态时,螺旋性振幅理论给出了它的角分布W_J.我们注意到.用这个角分布来确定X的自旋宇称存在着不灵敏区.本文对不灵敏区问题作了进一步研究.结果表明:1)确实存在着不灵敏区;2)θ(1720)的自旋宇称是2^(++)还是0^(++)尚不能最后肯定;3)窄峰ξ(2230)如果存在的话,可以排除其自旋宇称是0^(++)的可能性.
The spin-parity analysis of the J/φ radiative decay products into two pseudoscalars usually uses the angular distribution calculated by the helicity amplitude formalism. This paper investigated the sensitivity of this method and pointed out the followings: 1). there really exists some insensitive area; 2). unfortunately, θ(1720)falls into the insensitive area of 2^(++)-0^(++) distinction; so the spin of θ(1720) has not been finally established yet; 3). according to the Mark-3 data, for the newly observed very narrow peak ξ(2230), the spin 0^(++) assignment can be ruled out.
出处
《高能物理与核物理》
CSCD
北大核心
1990年第3期193-199,共7页
High Energy Physics and Nuclear Physics
