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Optical oscillator strengths of the valence-shell excitations of atoms and molecules determined by the dipole (gamma, gamma) method 期刊论文  OAI收割
EUROPEAN PHYSICAL JOURNAL D, 2017, 卷号: 71, 期号: 7, 页码: -
作者:  
Xu, LQ;  Liu, YW;  Xu, X;  Ni, DD;  Yang, K
  |  收藏  |  浏览/下载:207/0  |  提交时间:2018/08/30
Rare-earth doped tungsten tellurite glasses and waveguides: Fabrication and characterization (EI CONFERENCE) 会议论文  OAI收割
Physics of Non-Crystalline Solids 10, October 15, 2004 - October 15, 2004, Parma, Italy
作者:  
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
Tungsten tellurite glasses doped with Er3+  Tm3+  Pr3+  and Ho3+ ions were prepared by melt quenching. The glass matrix was the same for all types of glasses and had a high sodium content in order to allow the fabrication of waveguides using an ion-exchange technique. The absorption spectra of the glasses were measured and the Judd-Ofelt parameters q were obtained from the experimental oscillator strengths of the f &rarr f transitions. Er3+ doped glasses showed a very high quantum efficiency when comparing the calculated radiative decay time with the measured lifetime of the 4I 13/2 metastable level. Ag+ Na+ ion-exchanged planar waveguides were successfully obtained in all types of glasses and characterized by the prism coupling technique. It turned out that the diffusion constant values are very similar for glasses containing different rare-earth ions with the same concentration  while  at least for the Er 3+ doped ones  the diffusion constant changes with the ions concentration. 2004 Elsevier B.V. All rights reserved.  
硕士论文-J/ψ衰变到2(pai+pai-)°p和2(K+K-)终态的强衰变研究 学位论文  OAI收割
硕士, 北京: 中国科学院研究生院, 1991
作者:  
陈少敏
收藏  |  浏览/下载:23/0  |  提交时间:2015/10/12
The  J/Ψ  hadronic  decays  involving  2(π+π-)π°and  2(K+K-)  final  states  are  investigated  by  using  the  sample  of  2.5  *  10~6  J/Ψ's  which  were  obtained  from  the  BES  detector  at  BEPC  in  the  first  half  of  1990.  Some  signals  such  as  ω(782)  φ(1020)  f2(1270)  f2'(1525)  θ/f2(1720)  b1(1235)  and  a2(1320)  have  been  found  and  measured  the  mass  width  and  branching  fraction  of  reasonance  states.  The  results  are  agreement  with  the  world  average  values.  The  ratio  of  Br(J/Ψ    ω  f2(1270))/Br(J/Ψ→ρ°a2°)  shows  that  doubly  OZI  violating  effects  play  a  role  in  the  J/Ψ    ω  f2(1270)  f2(1270)    π+π-  are  given  in  the  first  time:  x  =  0.99  ±  0.29  Y  =  -0.24  ±  0.17  Z1  =  0.90  ±  0.57  Z2  =  0.56  ±  0.22.