MD-82
Air Traffic Control Fully Certified
Communication Breakdown; Confusion; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict
Air Traffic Control Issued New Clearance
Human Factors
The R-Side controller climbed a C680 to FL310 to go underneath a MD82. There was a NXXX also on frequency that had been leveled at FL310 for arrival traffic. The R-Side climbed NYXX to FL370 but meant to climb NXXX. I did not hear the clearance to be wrong. An MD82 and NYXX responded to a TCAS and the R-Side responded.
Enroute Controller described a loss of separation event when the R-Side Controller issued an altitude assignment to the wrong aircraft; similar call signs were in play.