Theme translation question

I'm setting up a custom theme I created for translation. I have this code in the footer:
<div id="footericons"><img src="<?php bloginfo('template_url'); ?>/images/icon-footer-rss.png" width="16" height="16" alt="rss feed" /><img src="<?php bloginfo('template_url'); ?>/images/icon-footer-linkedin.png" width="16" height="16" alt="connect with us on linkedin" /></div>

I'm not sure whether to use the _e( or the __( function for translating the alt. Seems like it should be an echo but I don't want to set a lot of stuff up and then find I have a lot wrong.