Confirmation of the X(1835) and Observation of the Resonances X(2120) and X(2370) in J/{psi}{yields}{gamma}{pi}{sup +}{pi}{sup -}{eta}'
With a sample of (225.2{+-}2.8)x10{sup 6} J/{psi} events registered in the BESIII detector, J/{psi}{yields}{gamma}{pi}{sup +}{pi}{sup -}{eta}' is studied using two {eta}{sup '} decay modes: {eta}{sup '}{yields}{pi}{sup +}{pi}{sup -}{eta} and {eta}{sup '}{yields}{gamma}{rho}{sup 0}. The X(1835), which was previously observed by BESII, is confirmed with a statistical significance that is larger than 20{sigma}. In addition, in the {pi}{sup +}{pi}{sup -}{eta}' invariant-mass spectrum, the X(2120) and the X(2370), are observed with statistical significances larger than 7.2{sigma} and 6.4{sigma}, respectively. For the X(1835), the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar.