On the analytic properties of intertwining operators I‎: ‎global normalizing factors

We provide a uniform estimate for the L1-norm (over any interval of bounded length) of the logarithmic derivativesý ýof global normalizing factors associated to intertwining operators for the following reductive groups over number fieldsý: ýinner forms of GL(n); quasi-split classical groups and their similitude groups; the exceptional group G2ý. ýThis estimate is a key ingredient in the analysis of the spectral side of Arthur's trace formulaý. ýIn particularý, ýit is applicable to the limit multiplicity problem studied by the authors in earlier papersý.