Let
$F$
be a
$p$
-adic field and choose
$k$
an algebraic closure of
$\mathbb{F}_{\ell }$
, with
$\ell$
different from
$p$
. We define βnilpotent liftsβ of irreducible generic
$k$
-representations of
$GL_{n}(F)$
, which take coefficients in Artin local
$k$
-algebras. We show that an irreducible generic
$\ell$
-modular representation
$\unicode[STIX]{x1D70B}$
of
$GL_{n}(F)$
is uniquely determined by its collection of RankinβSelberg gamma factors
$\unicode[STIX]{x1D6FE}(\unicode[STIX]{x1D70B}\times \widetilde{\unicode[STIX]{x1D70F}},X,\unicode[STIX]{x1D713})$
as
$\widetilde{\unicode[STIX]{x1D70F}}$
varies over nilpotent lifts of irreducible generic
$k$
-representations
$\unicode[STIX]{x1D70F}$
of
$GL_{t}(F)$
for
$t=1,\ldots ,\lfloor \frac{n}{2}\rfloor$
. This gives a characterization of the mod-
$\ell$
local Langlands correspondence in terms of gamma factors, assuming it can be extended to a surjective local Langlands correspondence on nilpotent lifts.