The coupling evolutions of stimulated Raman scattering (SRS) and Raman rescattering (re-SRS) are investigated under the parameter conditions of relevance to the gas-filled hohlraum experiments at the National Ignition Facility by using the nonenveloped fluid code FLAME. It is found that re-SRS works as a frequency filter of the backscattered light of SRS in the gas region. The low frequency modes of scattered light originated from a higher density region would stimulate re-SRS and be heavily depleted by re-SRS near the region of their quarter critical density. The energy in daughter waves of re-SRS is deposited in the gas plasmas. The large amplitude of the daughter Langmuir wave of re-SRS would stimulate cascade Langmuir decay instabilities and induce obvious low frequency density modulations, which can further result in the inflation of high frequency modes of scattered light of SRS at densities lower than the growth region of re-SRS.
誘導ラマン散乱(SRS)とラマン再散乱(re-SRS)の結合発展が、National Ignition Facilityにおけるガス封入ホーラム実験に関連するパラメータ条件下で、非包絡流体コードFLAMEを用いて調べられた。re-SRSがガス領域においてSRSの後方散乱光の周波数フィルタとして機能することが見いだされた。より高密度領域に由来する散乱光の低周波モードは、re-SRSを刺激し、それらの4分の1臨界密度の領域近傍でre-SRSによって大きく減衰されるであろう。re-SRSの娘波のエネルギーは、ガスプラズマ中に堆積される。re-SRSの娘ラングミュア波の大きな振幅は、カスケード・ラングミュア減衰不安定性を刺激し、明らかな低周波密度変調を誘発するであろう。これはさらに、re-SRSの成長領域よりも低い密度において、SRSの散乱光の高周波モードの増大をもたらし得る。