Hello and a question

Dear Friends,

Hello. I am new to this group but I am very glad to have found it.
I've been interested in this topic for a quite a while.

A quick question. One of the basic designs for space habitats seems
to be a torus or "ring town." The initial Stanford design, as I
recall, was a ring about 2 km. in diameter and 150 meters across.

Is there any reason the ring needs to be so narrow (relative to the
diameter)? Or was that just chosen because they only needed to house
a certain number of people? I would think it would be more efficient
to make "fat" rings (with more interior land area) if you're going to
build a ring-shaped habitat. Or would "fat" rings create special
engineering problems? Is there any limit on how "fat" the rings can
be? Could you, for example, have a 5-to-1 ratio (e.g., a ring 5 km.
in diamter with a floor width of 1 km.)?

Thanks. I look forward to reading your thoughts on this.

Mark