Breakup of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow/><mml:mrow><mml:mn>11</mml:mn></mml:mrow></mml:msup></mml:mrow><mml:mi mathvariant="normal">Be</mml:mi></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow/><mml:mrow><mml:mn>15</mml:mn></mml:mrow></mml:msup></mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:math>on light targets including core excitations

Longitudinal momentum distributions and total diffraction and stripping cross sections for production of ${}^{10}\mathrm{Be}$ and ${}^{14}\mathrm{C}$ fragments in ground and excited states, by removal of a valence neutron or a core neutron, are studied in the eikonal approximation for the ${}^{9}\mathrm{Be}{(}^{11}\mathrm{Be},$ ${}^{10}\mathrm{Be}+\ensuremath{\gamma})$ and ${}^{9}\mathrm{Be}{(}^{15}\mathrm{C},$ ${}^{14}\mathrm{C}+\ensuremath{\gamma})$ reactions. A consistent description of recent exclusive data for individual ${}^{10}\mathrm{Be}$ states is obtained, giving support to the procedure. Predictions for ${}^{14}\mathrm{C}$ are in agreement with available inclusive and limited inclusive data, and argue for halo model for ${}^{15}\mathrm{C}.$ The sensitivity of the results to the structural assumptions and interaction potentials is discussed.