  The best examples of halo nuclei, exotic systems with a diffuse nuclear cloud
surrounding a tightly-bound core, are found in the light, neutron-rich region,
where the halo neutrons experience only weak binding and a weak, or no,
potential barrier. Modern direct reaction measurement techniques provide
powerful probes of the structure of exotic nuclei. Despite more than four
decades of these studies on the benchmark one-neutron halo nucleus Be-11, the
spectroscopic factors for the two bound states remain poorly constrained. In
the present work, the Be-10(d,p) reaction has been used in inverse kinematics
at four beam energies to study the structure of Be-11. The spectroscopic
factors extracted using the adiabatic model, were found to be consistent across
the four measurements, and were largely insensitive to the optical potential
used. The extracted spectroscopic factor for a neutron in a nlj = 2s1/2 state
coupled to the ground state of Be-10 is 0.71(5). For the first excited state at
0.32 MeV, a spectroscopic factor of 0.62(4) is found for the halo neutron in a
1p1/2 state.
