宇宙线是来自宇宙空间的高能粒子流，由各种原子核以及非常少量的电子、光子和中微子等组成，它可能携带着宇宙起源、天体演化的信息，一直吸引着科学家的关注．

宇宙线粒子的能量范围非常大，有的可以高达5×10¹⁹eV．宇宙线逃逸出宇宙线源在星际空间中传播时，会与磁场、星际介质等发生相互作用，导致一系列复杂的物理效应产生．

利用空间探测器可以得到宇宙线在银河系中传播的一些数据，比如：铍10铍9比（ $\frac{Be10}{Be9}$ ），其中铍9是宇宙线中原有的铍10在传播过程中衰变产生的．

据此材料，以下叙述正确的是       

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    Bryan Forbes, who was born in London on 22 July 1926, made his first screen acting appearance in 1918.

    He landed supporting parts in several outstanding British films, including An Inspector Calls (1954) and The Colditz Story (1955), but it was not long before screen-writing and directing attracted him behind the camera. Together with Richard Attenborough, he set up Beaver Films in 1959. Its first film, The Angry Silence (1960), was written by Forbes and Attenborough played the lead role.

    His directing career began in 1961 with Whistle down the Wind, featuring child star Hayley Mills. Forbes directed many more films in the 1960s and early 1970s. In 1969 he took over as head of production and managing director of EMI—MGM Elstree, and the studio achieved outstanding successes. But it was a torrid time for the company. Troubled constantly by financial difficulties and staffing issues, Forbes quitted in 1971. He then directed The Step ford Wives, based on the novel by Ira Levin, and in 1975 International Velvet, starring Tatum O'Neal, in 1978.

    Forbes, who counted the late Queen Mother among his friends, continued directing, writing and acting throughout the 1980s and early 1990s. He also found success as an author with a number of novels, the latest of which, The Soldier's Story, was published last year.

    After Forbes passed away, film critic Mark Kermode said, “Once I had fun—boyish pleasure of telling Bryan Forbes how much I loved Step ford Wives. He was charming and modest. A great loss.”

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