Nancy Hargrove' book, T. S. Eliot's Parisian Year, is a wonderful and extensive account of what I assume is initially discussed here. As I said in a review of her book, it does not aim to identify every event or experience Eliot can be proven to have had but to define the fascinating culture he entered in Paris and the great range of new ideas and art and invention and philosophy (including important accounts of his attendance at Bergson's lectures).
It is a great read.
T. S. Eliot's Year Abroad, 1910-1911: The Visual Arts
Nancy D. Hargrove
South Atlantic Review
Vol. 71, No. 1 (Winter, 2006), pp. 89-131
One may read it for free.