Interaction of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>He</mml:mi><mml:mprescripts/><mml:none/><mml:mn>8</mml:mn></mml:mmultiscripts></mml:math> with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Pb</mml:mi><mml:mprescripts/><mml:none/><mml:mn>208</mml:mn></mml:mmultiscripts></mml:math> at near-barrier energies: <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>He</mml:mi><mml:mprescripts/><mml:none/><mml:mn>4</mml:mn></mml:mmultiscripts></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>He</mml:mi><mml:mprescripts/><mml:none/><mml:mn>6</mml:mn></mml:mmultiscripts></mml:math> production

Angular distributions for the inclusive $^{4}\mathrm{He}$ and $^{6}\mathrm{He}$ production cross sections in the $^{8}\mathrm{He}+^{208}\mathrm{Pb}$ system at incident energies of 16 and 22 MeV measured at the SPIRAL facility of the GANIL laboratory are presented. Using a combination of kinematical arguments and distorted wave Born approximation (DWBA) calculations, neutron transfer reactions were inferred to be the dominant contributors to both inclusive cross sections. Model-dependent values for the ratios of two- to one-neutron stripping, ${\ensuremath{\sigma}}_{2n}/{\ensuremath{\sigma}}_{1n}$, were derived and compared with previous results for $^{8}\mathrm{He}$ and $^{6}\mathrm{He}$ projectiles incident on other heavy targets. Three- and four-neutron stripping were inferred to be the main processes leading to $^{4}\mathrm{He}$ production, although the exact mechanism remains to be elucidated.

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