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本工作在HI-13串列加速器的次级束流线上进行。利用44MeV的7Li束轰击前后窗为1.9mg/cm2、气压为1.6×105Pa的氘气靶,通过2H（7Li,6He）3He反应产生6He。仔细调节次级束流线的D-Q-Q磁分离聚焦系统,得到能量为35.7 MeV、纯度好于90％的6He次级束。次级束中的主要杂质是7Li2+、7Li3+、4He2+和6Li2+。其中,6Li2+杂质虽很少但对次级反应的测量影响很大。为了剔除次级束中的7Li和6Li成分,在次级靶前放置一厚度为45.9mg/cm2的Al吸收片。通过吸收片后的6He束能量为25MeV,经φ3mm准直孔后打到厚度为1.5mg/cm2的（CH2）n靶上。用△E和PSSD测量次级反应的产物。 PSSD与（CH2）n靶的距离为95mm,覆盖的实验室系出射角度的范围为0～14°,可保证对反应产物6Li（最大出射角为12.8°）的全立
This work is carried out on the secondary beamline of the HI-13 Tandem Accelerator. 6He was produced by 2H (7Li, 6He) 3He reaction using a 44MeV 7Li beam bombarded with a deuterium gas target of 1.9 mg / cm 2 and an air pressure of 1.6 × 10 5 Pa. Carefully adjust the D-Q-Q magnetic separation focusing system of the secondary beamline to obtain a 6He secondary beam with an energy of 35.7 MeV and a purity of better than 90%. The main impurities in the secondary beam are 7Li2 +, 7Li3 +, 4He2 + and 6Li2 +. Among them, 6Li2 + impurities are minor but have a great impact on the measurement of secondary reactions. In order to eliminate the 7Li and 6Li components in the secondary beam, an Al absorbent sheet having a thickness of 45.9 mg / cm2 was placed in front of the secondary target. The energy of the 6He beam after passing through the absorption sheet was 25 MeV, and was punched through a φ3 mm collimation hole and struck on a (CH2) n target having a thickness of 1.5 mg / cm2. The product of the secondary reaction was measured by ΔE and PSSD. The distance between the PSSD and the (CH2) n target is 95 mm and the coverage angle of the laboratory system is in the range of 0 to 14 °. This ensures that the reaction product 6Li (maximum emission angle of 12.8 °)