粒子散乱の特徴とその関係

このQ&Aのポイント
  • この文章は、粒子の散乱特性とそれに関連する現象について述べています。
  • 粒子の散乱は、特定の範囲内で対称的なパターンを持ち、散乱が起こることが多いことがわかっています。
  • また、散乱の特徴は、初期の衝突パラメータと終了の衝突パラメータに関連しています。
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この文章の和訳を教えてください。

At first sight, from these figures, a symmetric pattern with respect to b_i~=0 holds approximately and a large scattering occurs in the region 1.5≦|b_i~|≦6. This is because a particle of which |b_i~| lies between 1.5 and 6 enters the Hill sphere and, hence, is scattered heavily. When |b_i~| is less than about 1.0, the feature of the scattering takes a new aspect. The gyrocenter of a particle comes slowly close to the planet whereas the particle rotates rapidly around the gyrocenter. When the distance between the planet and the gyrocenter is several times as short as the Hill radius, the gyrocenter of the particle gradually turns back to the opposite side of the y-axis, as if it were reflected by a mirror. The feature of the scattering is the same as that for the case e_i~=0. For the final impact parameter, b_f~, and the eccentricity, e_f~, we have again the relations b_f~=-b_i~ and e_f~=e_i~. (3・10) よろしくお願いします。

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  • ddeana
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回答No.1

これらの図から一見したところ、b_i~が0の場合に関する左右対称のパターンはおおよそ保たれており、大きな散乱は、b_i~の絶対値が1.5と同じかそれよりも大きく、6と同じかそれよりも小さな領域で起こる。これは1.5から6の間のb_i~の絶対値を持つ粒子がヒル球に入ることにより、激しく散乱するからである。 b_i~の絶対値が1.0ぐらいより小さい時、散乱の特徴は一変する。粒子それ自体がジャイロセンターの周りを急速に回転する一方、粒子個々のジャイロセンターはゆっくりと惑星に近づいていくのである。惑星とジャイロセンターの距離がヒル球の半径の数分の一ほど短くなった時、粒子のジャイロセンターは、あたかも鏡によって反射したかのように、徐々にY軸の反対側へと折り返していく。散乱の特徴はeが0の場合のそれと同じである。最終的な衝撃パラメーター b_f~と離心率 e_f~については、再び次のような関係となる。 b_f~=-b_i~ and e_f~=e_i~. (3・10)

stargazer1231
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