In jQuery, how do I select an element by its name attribute?

I have 3 radio buttons in my web page, like below:

<label for="theme-grey">
  <input type="radio" id="theme-grey" name="theme" value="grey" />Grey</label>
<label for="theme-pink">
  <input type="radio" id="theme-pink" name="theme" value="pink" />Pink</label>
<label for="theme-green">
  <input type="radio" id="theme-green" name="theme" value="green" />Green</label>

In jQuery, I want to get the value of the selected radio button when any of these three are clicked. In jQuery we have id (#) and class (.) selectors, but what if I want to find a radio button by its name, as below?

$("<radiobutton name attribute>").click(function(){});

Please tell me how to solve this problem.