Studies of autoionization and autodetachment resonances in atoms, molecules, ions and clusters

To understand the role of electron correlations and relativistic effects, it is of immense importance to throw light on photon-matter and matter-matter interactions which further aid in exploring the structure and dynamics of atoms, molecules and clusters. The present work focuses on the autoionization and autodetachment resonances in atoms, molecules and clusters. In the present talk, different approaches that are employed to probe these resonances and techniques developed towards these studies will be discussed. Firstly, many-body theoretical methodologies like relativistic random-phase approximation and relativistic multi-channel quantum defect theory have been employed to characterize these resonances in the neon isoelectronic sequence [1]. These resonances have also been experimentally probed in anion photodetachment studies because anions are being considered as best-suitable systems to study the role of electron correlations. For this, a state-of-the-art anion photoelectron spectrometer is designed and constructed which comprises of pulsed supersonic expansion discharge ion source coupled with time-of-flight (ToF) mass spectrometer, to select the anion of interest. A velocity-map imaging spectrometer is designed and constructed to measure the kinetic energy and angular distribution of photoelectrons [2]. In this talk, the results corresponding to the experimental setup constructed and anion photoelectron spectroscopy of   [3] will be presented. The talk also includes the discussion on two autodetaching states that are found to be accessible in our collision-induced dissociation experiments on . 

References:  

1.	M. Nrisimhamurty, G. Aravind, P. C. Deshmukh, and S. T. Manson, Phys. Rev. A, 91, 013404 (2015).
2.	Nrisimhamurty Madugula, Roby Chacko, Pranawa C Deshmukh, and Aravind Gopalan, J. Phys.: Conf. Ser., 635, 112115 (2015).
3.	G. Aravind, M. Nrisimhamurty, Rupali G. Mane, A. K. Gupta, and E. Krishnakumar Phys. Rev. A, 92, 042503 (2015).