FIG. 25: (Color online.) Cross-section of the p( $^{16}$O,$^{16}$N)X reaction (insert (a)), and $^{12}$C($^{16}$O,$^{16}$N)X reaction (insert (b)). Both reactions were studied at θ = 0 $^{◦}$, and T$_{beam}$ =900*A MeV. [36]. In the p( $^{16}$O,$^{16}$N)X spectra, insert (a), the positions of the central peaks do not correspond so well to the expected masses as the in previous spectra. On the other hand, the agreement in insert (b), describing the $^{12}$C($^{16}$O,$^{16}$N)X reaction is outstanding, since all peaks, including the structures at M=1004 MeV ( α ) and M=1044 MeV ( β ) are perfectly reproduced. Here an arbitrary background is introduced in order to simulate the inelastic scattering due to the excitation of $^{12}$C levels. The $^{27}$Al($^{20}$Ne,$^{20}$Na)X and the $^{27}$Al($^{20}$Ne,$^{20}$F)X reactions were measured at Saturne (SPES4), using a $^{20}$Ne incident beam of T=950 MeV/A, at θ = 0 ◦ [35]. The same analysis is done as above, based on the integration over two channels and the addition of narrow structures over a broad Δ ++ peak. The result is shown in Fig. 26. Here, again, the oscilla- tions are well reproduced, especially in the region between the nucleon and the Δ missing masses in insert (a). FIG. 26: (Color online.) Cross-section of the $^{27}$Al( $^{20}$Ne, $^{20}$Na)X reaction (insert (a)), and $^{27}$Al( $^{20}$Ne, $^{20}$F)X reaction (insert (b)). Both reactions were studied at θ = 0 $^{◦}$, and T$_{beam}$ =950*A MeV. [35]. This work analyses different cross-sections measured with incident hadrons, in order to increase the experimental signatures for the excitation of low mass narrow baryons previously observed. A large improvement is obtained in the description of the data by a fit, which takes narrow structures into account. The corresponding χ 2 values, which show such improvement, F. The $^{27}$Al( $^{20}$Ne, $^{20}$Na)X and the $^{27}$Al( $^{20}$Ne, $^{20}$F)X reactions X. CONCLUSION 17