As for ranks, one of the main metrics is citations. Keywords are also relevant. Once you are up to speed on a topic then you'll notice a few publications tend t

As for ranks, one of the main metrics is citations. Keywords are also relevant. Once you are up to speed on a topic then you'll notice a few publications tend to publish the good stuff, and so subscribing to them helps you feed off the paper firehouse. arXiv might be a source but hosting only preprints without peer review ends up lowering the average quality of the stuff that shows up in there.