As detect magic, except you immediately detect the strength and location of each charm, compulsion, and possession aura on all creatures in the area. You can attempt to identify the properties of each aura (see Spellcraft).

In addition to noticing the targets of these effects, you can recognize when creatures in the area are using these effects on others by making a Sense Motive check as a standard action (DC 20 + caster level). If you succeed, you may make a Spellcraft check to identify what magic it is using (even if the target is not in the area).