How to return query results to a variable using mongoose

I am still in learning stage of Node.js and Moongoose and i have a scenario where in

• I am taking value(ABC) from form submit.It is a user's Name
• Then i am searching for that name in users collection(User)
• Fetch that user and write its ObjectID in another schema(article) using ref.

My logic:

article.owner = User.findOne({ 'name' : 'ABC' })
    .exec(function (err, user){
         return user
    })

But it is not returning results. I referred some other answers and tried async.parallel but still i am not able to save ABC user's objectID in article schema at article.owner i am always getting null.

Please suggest me any other better ways.