  [Background] Alpha-nucleus optical potentials are basic ingredients of
statistical model calculations used in nucleosynthesis simulations. While the
nucleon+nucleus optical potential is fairly well known, for the alpha+nucleus
optical potential several different parameter sets exist and large deviations,
reaching sometimes even an order of magnitude, are found between the cross
section predictions calculated using different parameter sets. [Purpose] A
measurement of the radiative alpha-capture and the alpha-induced reaction cross
sections on the nucleus 115In at low energies allows a stringent test of
statistical model predictions. Since experimental data is scarce in this mass
region, this measurement can be an important input to test the global
applicability of alpha+nucleus optical model potentials and further ingredients
of the statistical model. [Methods] The reaction cross sections were measured
by means of the activation method. The produced activities were determined by
off-line detection of the gamma-rays and characteristic x-rays emitted during
the electron capture decay of the produced Sb isotopes. The
115In(alpha,gamma)119Sb and 115In(alpha,n)118Sbm reaction cross sections were
measured between Ec.m. = 8.83 MeV - 15.58 MeV, and the 115In(alpha,n)118Sbg
reaction was studied between Ec.m. = 11.10 MeV - 15.58 MeV. The theoretical
analysis was performed within the statistical model.
