The technique of intensity interferometry is proposed as a probe of the spa
tial configuration of two-neutron haloes. After exploring the sensitivity o
f interferometry to the n-n configuration, it is demonstrated that the appl
ication of the standard method for constructing the correlation function is
not valid for halo neutrons. A new iterative method is presented and appli
ed to measurements of the dissociation of He-6, Li-11 and Be-14. The correl
ation functions for these systems have thus been extracted for the first ti
me and the corresponding root-mean-square n-n separations estimated. The re
sults are in agreement with the predictions of available three-body models.
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