Experimental test of the ratio method to constrain the halo property of 11Be with BlueSteAl

A new method to constrain the properties of neutron-halo nuclei, the ratio method, was experimentally studied. The ratio method theoretically predicts that it is possible to constrain the single-particle state and the binding energy of a neutron-halo nucleus from the ratios of neutron breakup and elastic cross sections. We, therefore, tested the method to verify the predictions using a well-studied halo nucleus, ¹¹Be, and explored the possibility of further extending the method to more exotic halo nuclei in the future. We measured angular differential elastic and neutron breakup cross sections of ¹¹Be on ¹²C at 22.5 MeV/u at the Texas A&M University K500 cyclotron. The ¹²C target was bombarded with a ¹¹Be beam produced at MARS (Momentum Achromat Recoil Separator) spectrometer. Elastic ¹¹Be and neutron breakup ¹⁰Be were detected with the BlueSTEAl Si detector array that we developed recently. We will present preliminary results from our experiment.