Progresses of AMODS Database in KAERI and Electron Impact Ionization Cross Sections

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Progresses of AMODS Database in KAERI and Electron Impact Ionization Cross Sections Yongjoo RHEE Laboratory for Quantum Optics, Korea Atomic Energy Research Institute P.O.BOX 105 Yuseong, Daejeon 305-600 Republic of Korea yjrhee@kaeri.

1 Progresses of AMODS Database in KAERI and Electron Impact Ionization Cross Sections Yongjoo RHEE Laboratory for Quantum Optics, Korea Atomic Energy Research Institute P.O.BOX 105 Yuseong, Daejeon Republic of Korea Abstract. Online calculation tools for electron impact ionization cross sections based upon the MCDF and the BEB methods in collaboration with NIST have been added to the AMODS which has been established on the ground of the atomic spectroscopy studies carried out at the Laboratory for Quantum Optics in Korea Atomic Energy Research Institute (KAERI). Simulations of high density plasma physics have become one of the new research topics. AMO DATABASE IN KAERI Since the initial launch in 1997, AMODS (Atomic, Molecular, and Optical Database Systems) in KAERI has been evolved to contain many features of atomic spectroscopy and collisional processes. It is now recognized as the primary AMO database (DB) in Korea and is in service worldwide for the scientific communities requiring atomic and molecular (AM) data, including atomic structure and transition probabilities, electron impact excitation/ionization cross sections, and so on. It also provides services of real-time execution of AM data codes such as ALADDIN, MCDF, population dynamics for multiphoton ionization (MPI) of three-level atomic system, and so on. AMODS is a member data center of IAEA International Data Center Network (IDCN). FIGURE 1 is the first page of AMODS, showing buttons for numerical data in the left column and introduction of ASRG (Atomic Spectroscopy Research Group) at the right-top of the page, with list of member data centers of IDCN at the lower right part of the page. The database structure and raw data sources are shown in Figure 2. Most data retrieval is controlled by scripts written in PERL or FIGURE 1. AMODS webpage: korn shell in Unix based operating re.kr systems. As to the atomic spectroscopic data, comprehensive emission spectral lines of almost all the elements of the periodic table are compiled in user friendly ways. Data can be retrieved by element name or by wave length ranges. A script to extract transition lines to form a multi-step excitation path (such as for Grotrian

diagram) of the elements is also provided with the raw data being derived from the atomic spectral lines (ASL) sub-database which is already complied in AMODS, as shown in Figure 3.

Structure and data sources of AMODS calculation are compiled with graphical output format available.

2 diagram) of the elements is also provided with the raw data being derived from the atomic spectral lines (ASL) sub-database which is already complied in AMODS, as shown in Figure 3. For collisional data, crossbeam experimental data of oxygen molecule and theoretical data of oxygen, carbon, and nitrogen atoms obtained from MCDF FIGURE 2. Structure and data sources of AMODS calculation are compiled with graphical output format available. For oxygen molecule, differential cross sections of several excitation reactions as in Figure 4 can be obtained in graphical format, as well as in the original text format. FIGURE. 3. Atomic Spectral Lines Sub-database: Shown are the search screens of spectral lines of Sm I and corresponding search result. The inset in the lower left corner is the MPI paths for Yb I. For relativistic calculation of atomic structures, MCDF program code is also contained in AMODS together with brief manuals, lecture notes and videos, and can be executed on-line for real time calculation using Unix version of MCDF.

can be downloaded from this page with some examples, to be run in the user's own PC.

(Binary- Encounter-Bathe) model (Figure 5) with parameters which can be obtained from the

3 FIGURE 4. Electron impact excitation/ionization database Meanwhile, Windows version of MCDF binary code can be downloaded from this page with some examples, to be run in the user's own PC. Script for real time calculation of electron impact ionization cross sections based on BEB (Binary- Encounter-Bathe) model (Figure 5) with parameters which can be obtained from the output of MCDF calculation has been newly implemented (Figure 6 - Figure 8). FIGURE 5. Relativistic calculation of isotope shift for heavy metal element in AMODS using MCDF on-line execution code

FIGURE 6 Parameter input screen for online calculation of BEB FIGURE 8 To study the effect of each orbital, the atomic data for the specific orbital

This method can be used to study the highly charged ionic states of atoms.

For this calculation atomic parameters obtained from MCDF calculation for each orbital are used.

4 FIGURE 6 Parameter input screen for online calculation of BEB FIGURE 8 To study the effect of each orbital, the atomic data for the specific orbital can be tailored. Above screen shows the result of the BEB calculation with only n=4 orbitals. This method can be used to study the highly charged ionic states of atoms. FIGURE 7 Calculation result of electron impact ionization cross section for neutral Mo based on BEB method. For this calculation atomic parameters obtained from MCDF calculation for each orbital are used. International collaboration regarding AM data has been pursued towards the completion of AMODS. AMODS has a mirror DB of NIST ASD database as shown in Figure 9 and KAERI has been a member of ADAS consortium which contains lots of atomic data for fusion research. KAERI has been working with NIFS for DB of auto-ionization levels and dielectronic satellite lines, establishing a joint DB of

5 them as shown in Figure 10. FIGURE 9. Mirror DB of NIST ASD in AMODS FIGURE 10. Dielectronic satellite lines DB developed by NIFS and KAERI Recently studies about the high density plasma physics have been carried out in our laboratory. Figure 11 shows the ion density profile at the time of 40T, 70T and 100T where T is the period of electromagnetic wave of laser beam, in a one dimensional plasma slab. From the propagation of the wave front we calculated the velocity of the shock wave front of the ions, which was found out to be about 5 X 10 6 m/s according to the snapshots of the simulation. 200 ions at 40 T 200 ions at 70 T 200 ions at 100 T number of macro particles 100 number of macro particles 100 number of macro particles simulation box simulation box simulation box FIGURE 11. Propagation of shock wave front of ions in the plasma slab ATOMIC STRUCTURE AND SPECTROSCOPY STUDIES Experimental data on isotope shifts and hyperfine structures of some lanthanide elements obtained using the high resolution resonance ionization spectroscopy apparatus as shown in Figure 12 and Figure 13 have been compiled in AMODS. Lanthanide elements used to be the major concern because of their huge applications in the industries, and so far La[1], Eu, Gd[2] Sm[3], Dy, Er, and Yb[4] of lanthanides are investigated.

FIGURE 12. Apparatus for high resolution atomic spectroscopy in KAERI FIGURE 13. CW narrow band diode laser system for high resolution spectroscopy in IR and UV.

environmental protection and monitoring of nuclear power plant for safety enhancement.

6 FIGURE 12. Apparatus for high resolution atomic spectroscopy in KAERI FIGURE 13. CW narrow band diode laser system for high resolution spectroscopy in IR and UV. The isotopic data are important for the nuclear applications such as resonance ionization mass spectrometry, laser isotope separation, ultra high trace analysis, and so on, which are essential to the environmental protection and monitoring of nuclear power plant for safety enhancement. Figure 14 shows the high resolution spectrum of neutral Sm measured with CW narrow band diode laser system using the saturation absorption spectroscopy. The figure shows that the resolution of the measurement is 8 MHz and isotope shifts are clearly resolved. Figure 15 shows the multi-step excitation paths of Gd I in the UV wave length range. Usually lanthanide elements have very large transition probabilities near 400nm and this feature can be used for the FIGURE 14. An example of high resolution spectrum data (absorption spectrum of nm transition line of Sm I ) FIGURE 15. Selective photo-ionization paths of Gd I in UV range: Usually lanthanide elements have large transition probabilities near 400 nm wavelength range.

7 efficient isotope separation systems using solid-state tunable Ti:sapphire laser systems. Population dynamics calculation code based on the density matrix formalism is provided to allow the theoretical analysis of the population transfer in a three-level atomic system[5]. With the input data about the atomic structure and about the laser specification, this code calculate the population of each level of atomic system as a function of time as shown in Figure 16. This information is useful to determine the optimum condition of the MPI processes. FIGURE 16. Real-time execution result of population dynamics code based on the density matrix formalism (applied to Yb I) CONCLUSIONS The AMODS is now expanding to include more data relevant to fusion research and continues to pursue active international collaborations. As a step toward the fusion research the online calculation tools for electron impact ionization cross sections have been added. Such calculations as for Mo/Mo +, W/W +, Li, Be, V have been carried out recently in collaboration with NIST. A DB relevant to the high density physics will be implemented in AMODS in a near future. REFERENCES 1. H.M.Park, I.O.Chae, M.R.Lee, E.C.Jung, Y.J.Rhee, J.M.Lee, J of Korean Physical Society, vol 39 No 5 pp ( ) 2. J.T.Kim, J.H.Yi, Y.J.Rhee, J.M.Lee, J of Korean Physical Society, vol 37 no 5,pp ( ) 3. H.M.Park,M.R.Lee, Y.J.Rhee, J of Korean Physical Society, vol 43 No 3 pp (2003.9), Y.J.Rhee, H.M.Park, J.M.Lee, Chinese Journal of Lasers, Vol. B 10 III 8- III 13 (2001.4), H.M.Park, M.R.Lee, E.C.Jung, J.H.Yi, Y.J.Rhee, J.M.Lee, J. of Optical Society of America B vol 16 no 7, 1169 ( ) 4. A.S.Choe, Y.J.Rhee, S.P.Rho, J.M.Lee, J of Korean Physical Society, vol 28, no 1, pp89-95 ( ), A.S.Choe, Y.J.Rhee, J.M.Lee, M.A.Kuzmina, V.A.Mishin, J. of Physics B, At. Mol. Opt Phys. vol 28, 3805 ( ) 5. A.S.Choe, Y.J.Rhee, J.M.Lee, P.S.Hahn, S.K.Borisov, M.A.Kuzmina, V.A.Mishin, Physical Review A, vol 52 no 1, 382 ( )

Lecture 3 Numerical Data

Atomic, molecular and particle-surface interaction web databases and data exchange Lecture 3 Numerical Data ICTP Workshop on Atomic and Molecular Data for Fusion Energy Research Trieste, 20-30 April 2009