t the only one hunting for a W and a Z, however. Another detector collabora- 2P_GrealesiSleryEverTold_AC.indd 262 12/16116 3:06 PIA EFTA00286174 Spanking the Vacuum 253 tion had been assembled and was also built at CERN. Redundancy for such an important observation seemed appropriate. Unearthing a signal from