They can't be carpenter ants because they lack a large petiolar scale. They more closely resemble ants in the genus Tapinoma, but I can't ID them with certainty.

Great photo! I wish mine looked that good.

I noticed some large ants outside my home. I thought at first they are carpenter ants due to their large size, but I was told they are likely not. I saw them eating on a dead pigeon. Here is an image of them on the pigeon organ, see if you can identity them. http://s28.postimg.org/itt7cr8nh/IMG_7754x.jpg