I'm not sure if I know an official list. People frequently cite adult-level reading in fields such as Law, Science, Psychology, Art.
So publications like
The New Yorker
The Economist
Scientific American
are all good.
I am actually a bigger proponent of just reading more LSAT RC passages (if you have access to older tests, just read those RC passages for pleasure). In addition to exposing you to LSAT-type topics, it will also deepen your subconscious sense of how LSAT passages are structured/edited.
And if you're really just trying to quickly ramp up on lots of different topics in the world, books like "Intellectual Devotional" are nice, because they give you little one page summaries of a given topic / person / event.
https://www.amazon.com/Intellectual-Dev ... 1594865132You could probably check one out of the library.