The next state up in mass is the spin ⁠ 3 / 2 ⁠ state, usually known as the Σ c or the Σ c (2520). These are clearly going to be "wider" because of the extra phase space of their decay, which like the Σ c (2455) is to one pion plus a ground-state Λ c. Again, large statistics are necessary to claim a signal above the large number of Λ c - π pairs that are produced. Again, the neutral and doubly charged states are experimentally easier to detect, and these were discovered in 1997 by the CLEO Collaboration. The singly charged state had to wait till 2001 by the time they had collected more data.