In any dimension
N≥1, for given mass
a>0, we look to critical points of the energy functional
I(u)=21∫RN∣∇u∣2dx+∫RNu2∣∇u∣2dx−p1∫RN∣u∣pdx constrained to the set
Sa={u∈X∣∫RN∣u∣2dx=a},
where
X:=\left\{u \in H^1(\mathbb{R}^N)\Big| \int_{\mathbb{R}^N} u^2|\nabla u|^2 dx <\infty\right\}.
We focus on the mass super-critical case
4+\frac{4}{N}0
when1\leq N\leq 4
.ForN\geq 5
,wefindanexplicitnumbera_0
suchthattheexistenceofminimizeristrueifandonlyifa\in (0, a_0]$.
In the mass super-critical case, the existence of a minimizer to the problem
Ma, or more generally the existence of a constrained critical point of
I on
Sa, had hitherto only been obtained by assuming that
p≤2∗. In particular, the restriction
N≤3 was necessary.
We also study the asymptotic behavior of the minimizers to
Ma as the mass
a↓0, as well as when
a↑a∗, where
a∗=+∞ for
1≤N≤4, while
a∗=a0 for
N≥5.