How to check RMAN backup channels

set lines 200
set pages 200


select s.sid,p.spid,s.client_info
from v$process p, v$session s
where p.addr = s.paddr and client_info like '%rman%';



       SID SPID                     CLIENT_INFO
---------- ------------------------ ---------------------------
      1187 20672                    rman channel=ORA_DISK_5
      1224 20673                    rman channel=ORA_DISK_6
      1628 20674                    rman channel=ORA_DISK_7
       268 20667                    rman channel=ORA_DISK_1
       656 20668                    rman channel=ORA_DISK_2
       844 20669                    rman channel=ORA_DISK_3
       962 20671                    rman channel=ORA_DISK_4
      1665 20685                    rman channel=ORA_DISK_8
      2087 20731                    rman channel=ORA_DISK_13
      2386 20692                    rman channel=ORA_DISK_9
      2536 20705                    rman channel=ORA_DISK_10
      2723 20710                    rman channel=ORA_DISK_11
       875 20719                    rman channel=ORA_DISK_12
      2220 20732                    rman channel=ORA_DISK_14
      2625 20733                    rman channel=ORA_DISK_15
      2667 20738                    rman channel=ORA_DISK_16

16 rows selected.