The isovector response in ${}^{12}\mathrm{B}$ was investigated via the ${}^{12}\mathrm{C}({}^{10}\mathrm{Be},{}^{10}\mathrm{B}+\gamma ){}^{12}\mathrm{B}^{*}$ reaction at $100A\mathrm{MeV}$. By utilizing the $\gamma$-decay properties of the 1.74 MeV $0^{+}$ and 0.718 MeV $1^{+}$ states in ${}^{10}\mathrm{B}$, the separate extraction of the non-spin-transfer ($\mathrm{\Delta }S=0$) and spin-transfer ($\mathrm{\Delta }S=1$) isovector responses up to an excitation energy of 50 MeV in ${}^{12}\mathrm{B}$ in a single measurement is demonstrated. The experimental setup employed the S800 spectrometer to detect and analyze the ${}^{10}\mathrm{B}$ ejectiles and the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) for obtaining the Doppler-reconstructed spectrum for $\gamma$ rays emitted in flight by ${}^{10}\mathrm{B}$. A ${}^{12}\mathrm{C}$ foil was placed at the pivot point of the spectrograph. The ${}^{12}\mathrm{B}$ reaction product was not detected. Contributions from transitions associated with the transfer of different units of angular momentum in the non-spin- and spin-transfer responses were analyzed using a multipole decomposition analysis. The extracted non-spin-dipole ($\mathrm{\Delta }S=0, \mathrm{\Delta }L=1$) and spin-dipole ($\mathrm{\Delta }S=1, \mathrm{\Delta }L=1$) responses were found to be consistent with available data from other charge-exchange probes, validating the non-spin- and spin-transfer filters used. While statistical uncertainties and experimental resolutions were relatively large due to the modest intensity of the ${}^{10}\mathrm{Be}$ secondary beam, the results show that, with the much higher intensities that will be available at new rare-isotope beam facilities, the (${}^{10}\mathrm{Be},{}^{10}\mathrm{B}+\gamma$) reaction and its $\mathrm{\Delta }{T}_z=-1$ partner, the (${}^{10}\mathrm{C},{}^{10}\mathrm{B}+\gamma$) reaction, are powerful tools for elucidating the isovector non-spin- and spin-transfer responses in nuclei.

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• Charge-exchange reactions
• Collective levels
• Collective models
• Direct reactions
• Giant resonances
• Low & intermediate energy heavy-ion reactions
• Nuclear reactions
• Nuclear spin & parity
• Nuclear structure & decays
• Shell model
• Unstable nuclei induced nuclear reactions