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The $^{22}$Ne($\alpha$,n)$^{25}$Mg reaction is the dominant neutron sourcefor the slow neutron capture process ($s$-process) in massive stars andcontributes, together with the $^{13}$C($\alpha$,n)$^{16}$O, to the productionof neutrons for the $s$-process in Asymptotic Giant Branch (AGB) stars.However, the reaction is endothermic and competes directly with the$^{22}$Ne($\alpha,\gamma)^{26}$Mg radiative capture. The uncertainties for bothreactions are large owing to the uncertainty in the level structure of$^{26}$Mg near the alpha and neutron separation energies. These uncertaintiesare affecting the s-process nucleosynthesis calculations in theoretical stellarmodels. Indirect studies in the past have been successful in determining theenergies, $\gamma$-ray and neutron widths of the $^{26}$Mg states in the energyregion of interest. But, the high Coulomb barrier hinders a direct measurementof the resonance strengths, which are determined by the $\alpha$-widths forthese states. The goal of the present experiments is to identify the criticalresonance states and to precisely measure the $\alpha$-widths by $\alpha$transfer techniques . Hence, the $\alpha$-inelastic scattering and$\alpha$-transfer measurements were performed on a solid $^{26}$Mg target and a$^{22}$Ne gas target, respectively, using the Grand Raiden Spectrometer atRCNP, Osaka, Japan. Six levels (E$_x$ = 10717 keV , 10822 keV, 10951 keV, 11085keV, 11167 keV and 11317 keV) have been observed above the $\alpha$-thresholdin the region of interest (10.61 - 11.32 MeV). The rates are dominated in bothreaction channels by the resonance contributions of the states at E$_x$ =10951, 11167 and 11317 keV. The E$_x$ =11167 keV has the most appreciableimpact on the ($\alpha,\gamma$) rate and therefore plays an important role forthe prediction of the neutron production in s-process environments.

Probing astrophysically important states in $^{26}$Mg nucleus to study neutron sources for the $s$-Process