Speaker: Roger Hutton
Shanghai EBIT Lab., Fudan University. Shanghai, China
Time: 05/18 周五下午2点，器材楼207
In this contribution we will present a newly proposed method for a possible measurement of the corona magnetic field strength based on an accidental degeneracy of two quantum states of Fe9+. This degeneracy is between two quantum states of Fe9+, namely the 4D7/2 and 4D5/2 of the 3p43d electronic configuration. The 4D7/2 state is forbidden to decay to the ground state whereas the 4D5/2 has an allowed transition. However, the presence of an external magnetic field leads to quantum interference between these two states and opens up an allowed channel for the 4D7/2, we call this a Magnetic Induced Transition, MIT. The rate of MIT transitions depends on the strength of the external magnetic field, hence, a ratio of the transitions from these two 4D states can be used as a measure of the field strength. A very important parameter for this method to work is the closeness, in energy, of the degeneracy of the two states involved. We have measured this for the two 4D states in Fe9+ using the very unique properties of Electron Beam Ion Traps, EBITs. We find the two 4D states to be separated by 3.5 cm-1, which is less than 1/100000 of the 4D energy levels above the ground state. We also present a measurement of this fine structure energy based on spectroscopic data from the corona recorded using a spectrometer aboard space-lab.
CV of Professor Roger Hutton
University of Birmingham, England, 1974-1977, Bsc. in Mathematical Physics
Imperial College, University of London, 1977-1978, Msc. in Applied Optics
Queen Elizabeth College (London), 1978-1979, London, research student in optics
Lunds Universitet, Sweden, 1983-1988, Phd. in Atomic Spectroscopy. Supervisor Professor Indrek Martinson,
Lawrence Berkeley/Livermore Laboratories, 1988-1990
Manne Siegbahn Laboratory, Stockholm, 1990-1991.
Researcher, Atomic Spectroscopy, Lunds Universitet, 1991-1994
Associate Professor, Atomic Spectroscopy, Lunds Universitet, 1994-2002.
Associate Professor, Astronomi, Lunds Universitet, 2002 – 2005
Full Professor, Modern Physics Institute, Fudan University, Shanghai, China, 2005 –
Over 80 publications in refereed journals covering fields from atomic spectroscopy to collisions of slow and ultra-relativistic particles.
Publications, which I have been involved with, have been cited in over 300 papers where I am not an author.
Numerous grants from Swedish and EU agencies.
2007 Natural Science Foundation of China, X ray detection development, 1.8 million Chinese Yuen. Also grants for fusion related spectroscopy (nsfc) and detector development in Japan.
Co-chaired five international workshops in recent years and co-edited proceedings for three of the meetings. Co-editor on a book on the Physics of Highly Charged Ions (Taylor and Fransic 2011). Member of the international organizing committees for the following conferences: Physics of Highly Charged Ions (HCI), Atom Structure and Oscillator Strengths (ASOS) and Physics of Electronic, Atomic and Photonic Collisions (ICPEAC).