Actually, you might just offer the mom a treat and see if she comes to you, but don't try and pick her up until you are very certain she is a domestic rat... Wild rats can inbreed with domestic rats and the second generation offspring can look pretty domestic like.
In the photo below one of the rats is a domestic rat that loved everyone, and did meet and greets with hundreds of children and adults, she even entertained at handicapped children's events... the other rat was part wild and would tear your hands to shreds if she didn't know you and you tried to pick her up... She was raised by my daughter in the photo but then lived outside on her own for 5 months prior to this photo being taken...
If you don't think you can tell which is which... don't try and handle the rats in your yard... get someone who knows what they are doing to trap the rats for you... The pups are even more likely to be part wild... they can become pets if they get enough love and attention by the right human before they are too old to become too dangerous to handle.
Perhaps someone local to you can help or put you in touch with a rat rescue.