摘要
The Coulomb explosion of ammonia clusters induced by nanosecond laser at 532 nm with an intensity of ~1012 Wcm-2 has been studied by time of flight mass spectrometry. The dominant multiply charged ions are N3+ and N2+ with kinetic energies of 110 and 50 eV respectively. The electrons generated from the multiphoton ionization are heated through inverse bremsstrahlung by the laser field when colliding with neutral or ionic particles. When their energies surpass the corresponding ionization potentials of the molecules or ions, the subsequent electron impact ionization may take place thus resulting in multi-charged nitrogen ions. Covariance analysis is made to study the possible pathways of the Coulomb explosion.
The Coulomb explosion of ammonia clusters induced by nanosecond laser at 532 nm with an intensity of ~1012 Wcm^-2 has been studied by time of flight mass spectrometry. The dominant multiply charged ions are N^3+ and N^2+ with kinetic energies of 110 and 50 eV respectively. The electrons generated from the multiphoton ionization are heated through inverse bremsstrablung by tbe laser field when colliding with neutral or ionic particles. When their energies surpass the corresponding ionization potentials of the molecules or ions, the subsequent electron impact ionization may take place thus resulting in multi-charged nitrogen ions. Covariance analysis is made to study the possible pathways of the Coulomb explosion.
基金
supported by the Hi-Tech Research and Development Program of China(Grant No.2005AA649010)
the Center for Computational Science,Hefei lnstitutes of Physical Sciences.
关键词
协方差分析
激光电离
氨水
氮离子
相关性系数
laser ionization, ammonia, multi-charged nitrogen ions, Coulomb explosion, correlation coefficient, time of flight mass spectrometry.