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⁹He has been observed in the ⁹Be(¹⁴C, ¹⁴O) reaction at E(¹⁴C) = 158 MeV (87BEYI) and in the ⁹Be(π^-, π⁺) reaction at E_π^- = 180 and 194 MeV (87SE05): the atomic mass excesses are 41.5 ± 1.0 MeV and 40.80 ± 0.10 MeV, respectively. We adopt the latter value. ⁹He is then unstable with respect to decay into ⁸He + n by 1.13 MeV. (87SE05) also report the population of excited states of ⁹He at 1.2, 3.8 and 7.0 MeV, while (87BEYI) suggest an excited state at ~ 1.8 MeV with Γ ~ 3 MeV. Excited states are calculated at 1.64, 3.86 and 6.53 MeV, with J^π = 1/2⁺, 5/2⁺ and 3/2^- [(0 + 1)h-barω model space]. In the (0 + 2)h-barω model space the normal-parity excited states are at 6.44, 29.09 and 29.42 MeV with J^π = 3/2^-, 7/2^-, 3/2^-. In both cases the ground state is J^π = 1/2^-, as would be expected (85PO10). See also (84BE1C, 88BEYJ), (85AL1G, 85SE1B, 86FL1A, 86FL1B, 87HA1R, 87PE1C, 88SE1C) and (83ANZQ, 84VA06, 86AN07, 87GI1C, 87IK1B; theor.).