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Active Beam Spectroscopy (Evaluation of Data and Supporting Software). Manfred von Hellermann FOM Institute for Plasma Physics Rijnhuizen, NL. Seminar-II Institute for Plasma Physics Academy of Sciences Hefei, China May, 6, 2007. Acknowledgement:
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Active Beam Spectroscopy (Evaluation of Data and Supporting Software) Manfred von Hellermann FOM Institute for Plasma Physics Rijnhuizen, NL Seminar-II Institute for Plasma Physics Academy of Sciences Hefei, China May, 6, 2007 Acknowledgement: CXRS groups at JET, TEXTOR, Tore Supra , ASDEX-UG and members of the ITPA expert group on Active Beam Spectroscopy
Outline • Basic concepts of quantitative spectroscopy • Spectral Analysis code KS4FIT ( KS4FIT_JAVA, CXSFIT) • CHEAP • Simulation of CXRS and BES Spectra M. von Hellermann
CX spectral fitting M. von Hellermann
Spectral Analysis Code KS4FIT • developed at JET ( 1986 to 1999) • The KS4FIT concept: • Approximation of observed spectra by • Active (beam induced) and non-active • features. Active features may be Gaussian- • shaped or modelled synthetic spectra • Atomic modelling of each feature to achieve • best possible initial estimates for non- • linear least square routine • b) unique identification of each component M. von Hellermann
Multi-machine (and multi spectrometer) access: JET TEXTOR Tore Supra Wega ASDEX-UG Data input: Raw Data Web Umbrella MDS plus Local Files NetCDF Data output: Processed Data U-file Local Files JET-PPF NetCDF Local Files: Geometry Calibration Dispersion Instrument Function M. von Hellermann
Technical aspects: Spectral Fit code available on Linux platform presently 3 different versions coexist: KS4FIT on JET ( Fortran only) CXSFIT on JET, ASDEX-Upgrade, KS4FIt Fortran core with interactive IDL control shell, to be distributed as ADAS package KS4FIT_JAVA on TEXTOR, W7-X, Tore-Supra and JET KS4FIT Fortran core with JAVA shell Local output formats are machine specific: PPF (JET), U-File (TEXTOR), Shot-File (AUG), MDS-Plus possible Local geometry, calibration, dispersion and instrument function files M. von Hellermann
Universal physics oriented features: • Standard setting files for the main low-Z CX transitions • Carbon • Helium • Beryllium • Neon • Argon • Nitrogen • Oxygen • Hydrogen, Deuterium, Tritium • And twin CX spectra M. von Hellermann
KS4FIT features • Physics wavelength units • Physics descriptions of components • Constant parameters • Coupled parameters • Synthetic pedestal shapes • Parameter estimate optimisation • 1) adjacent tracks • 2) previous frames • 3) pcx approximation • 4) amplitude updates • 5) input from other CX spectra • Suppressed components scenario • Parameter constraints • Documentation of settings M. von Hellermann
Schematic presentation of PCX emission process. The neutral density profile is the least known ingredient of the model. Pragmatic reconstruction of PCX feature by ACX close to separatrix ‘Modelling of Passive Charge Exchange Emission and Neutral Background Density Deductions in JET’ M. Tunklev, P. Breger, K. Günther, M. von Hellermann, R. König, M. O’Mullane and K-D. Zastrow Plasma Physics and Controlled Fusion’, 41,985-1024(1999) M. von Hellermann
Pragmatic treatment of non-gaussian PCX feature M. von Hellermann
He-beam injection at JET 1991 M. von Hellermann
CX nitrogen spectrum at JET M. von Hellermann
JET CVI spectrum in the presence of Argon ( Radiation cooling) M. von Hellermann
Role of edge lines on spectral wings M. von Hellermann
TEXTOR hydrogen scan experiment M. von Hellermann
JET DT pulse M. von Hellermann
CHEAP • Charge Exchange Analysis Package • Main function: • Mapping of plasma parameters on flux coordinates • Self consistent calculation of local impurity densities • from CX intensities, • atomic emission rates and local beam densities • c) Beam-target interaction physics • d) Global consistency checks M. von Hellermann
CHEAP continued • CHEAP exists presently in 3 versions: • At JET: LINUX , Fortran 77 and • local copies of ADAS files • b) At TEXTOR and Tore Supra: Linux, Matlab • data input routines and MEX fortran files, • local copies of ADAS files • c) At ASDEX: Linux, IDL M. von Hellermann
Thermal energy Ion pressure
Plasma dilution Error in dilution factor
W-dia, JET Experimental Campaign 1997 M. von Hellermann
Ralf König 1997 M. von Hellermann
Simulation of Spectra • Creation of synthetic spectra based on plasma • environment and atomic data. • Active features (thermal and fast ions) • Passive features (continuum, edge lines, PCX) • Sensitivity analysis for parameter retrieval • Optimization of instruments • Optimization of neutral beam specification M. von Hellermann
MATLAB simulation package includes presently: • ITER • JET • TEXTOR • ASDEX • Tore Supra • W7-X • HL-2A • HT-7 • EAST • SST M. von Hellermann
Simulation Structure: • Use CAD data for geometry • a) first-mirror coordinates • b) DNB injection coordinates • c) Torus geometry • Use DNB specifications • 3) Modelling of periscope imaging properties • 4) Use Spectrometer and CCD specifications • 5) CHEAP modelling of neutral beam stopping (ADAS) • CHEAP modelling of DNB excited population (ADAS) • CXRS and BES emission rates (ADAS) • Modelling of q-profile and pitch angle • Modelling of continuum radiation • Modelling of neutral density and PCX emissivity • Creation of Non-Thermal Synthetic spectra • Modelling of DNB modulation effects • Assessment of noise performance • Assessment of parameter errors M. von Hellermann
Summary remarks • Three main tools for the evaluation of active spectra have been developed • Key ingredients are advanced atomic modelling of beam plasma interaction processes • The modelling includes also background spectral features such as free-free continuum radiation and passive line emission at the plasma edge • A comprehensive documentation of background lines allows the analysis of complex spectra • Non-thermal features ( slowing-down etc.) are included M. von Hellermann