The nuclear models have to be constrained using experimental data collected on weakly bound nuclei in order to improve their predictive power. The one and two neutron transfer reactions 8He(p,d)7He and 8He(p,t)6He were mesured in inverse kinematics at GANIL. The 8He beam, impinging on a proton target, was produced at 15:4 MeV=n by the SPIRAL facility. The experimental setup consisted of four MUST2 telescopes for the detection of the light charged particles, of one MUST2 telescope to identify the heavy projectile, and of two beam tracking detectors CATS to reconstruct the incident position and angle of the beam on the target. A complete analysis of the data taken with MUST2 was done for the rst time. The performances of the detector were characterized, methods were developed for the calibrations and the selection of the events. The excitation energy spectra for 6;7He and the angular distributions of the cross-sections were extracted. The resonant states of 6He were observed at the following excitation energies : at 1:8 MeV (known), at 2:65(25) MeV with a width 􀀀 = 1:6(4) MeV, and at 5:3(3) MeV, 􀀀 = 2(1) MeV. One resonant state was observed for 7He at 1:3(2) MeV, with a width 􀀀 = 0:7(5) MeV. Our data do not exclude the controversial state at 0:9 MeV, 􀀀 = 1 MeV. These results were obtained with the very good position and energy resolutions of MUST2. They are consistent with the calculations of the nuclear theories which include the treatment of the coupling to the continuum and the eects of the three-body interactions.