I went to the Arizona-Sonora Desert Museum this morning to look into doing some volunteer work and while I was there I spent half an hour in the hummingbird aviary. It happened to be pretty quiet at the time which is when it's the most enjoyable for me and the birds I'm sure. This Broad-tailed Hummingbird was pretty active allowing me to get fairly close but chasing away the Costa's when ever they ventured too close.
This photograph does really good job of showing all the identifying characteristics. As you can see this little guy has been banded on his left leg. For this species more than 2/3rd's of Arizona is in it's summer or breeding range. More information on the Broad-tailed Hummingbird can be found at: http://identify.whatbird.com/obj/221/overview/Broad-tailed_Hummingbird.aspx