Understanding launch file from nav2d tutorial

I have a node that I want to subscribe two topics from nav2d, I'm interested to use the /base_scan and /odom topics. When I look in launch files then I can see ` ` I know that "scan" in stage that is remapped to the "base_scan" topic. But what is the remap name for /odom or /base_pose_ground_truth topic ? Or where can I find it ? Can I for example name /odom topic as `` ?