Ma. Shubov, HIGH-ENERGY ASYMPTOTICS OF RESONANCES FOR 3-DIMENSIONAL SCHRODINGER OPERATOR WITH SCREENED COULOMB POTENTIAL, Journal of mathematical physics, 35(2), 1994, pp. 656-674
Resonances for one-particle three-dimensional Schrodinger operators wi
th Coulomb potential perturbed by a spherically symmetric compactly su
pported function q(r) are studied. The mth derivative of q(r) has a ju
mp on the boundary of the support (m greater-than-or-equal-to 0). Reso
nances are defined as poles of an analytical continuation of the quadr
atic form of the resolvent to the second Riemann sheet through the bra
nch cut along the continuous spectrum. It is shown that there exists a
n infinite set of resonance poles which splits into an infinite sequen
ce of infinite series corresponding to different values of an angular
momentum. Resonances in each series have the only point of accumulatio
n at infinity. The main result of the work is an asymptotic formula fo
r resonances in each series. It follows from this formula that high-en
ergy resonances of the above operator are asymptotically close to thos
e of the Schrodinger operator with the same potential q(r) but without
Coulomb term. It was shown in one of the previous works of the author
that, in contrast with the non-Coulomb case, some perturbations q(r)
of the Coulomb potential can produce a sequence of resonances convergi
ng to zero. The result of this work together with the above result sho
ws that the Coulomb part of the potential, while dramatically changing
the geometry of resonances at low energies, does not destroy their as
ymptotic behavior at high energies.