TJ-II:Spectroscopy: Difference between revisions

[[TJ-II]] disposes of an nine-channel, high-resolution, spectroscopic diagnostic system. This system is currently being used to measure impurity ion temperature and poloidal rotation using passive emission spectroscopy. The principal features of the diagnostic include independent focusing of its channels, high sensitivity for performing Doppler measurements in plasmas, as well as a flexible and fast in-house-developed software program for performing integrated data reduction and analysis.

<ref>[http://link.aip.org/link/?RSINAK/72/971/1 A. Baciero et al, ''A multi-channel spectroscopic system for measuring impurity ion temperatures and poloidal rotation velocities in TJ-II'', Rev. Sci. Instrum. '''72''' (2001) 971]</ref>

<ref>[http://www.new.ans.org/pubs/journals/fst/a_1264 B. Zurro et al, ''Comparison of Impurity Poloidal Rotation in ECRH and NBI Discharges of the TJ-II HELIAC'', Fusion Science and Technology '''50''', 3 (2006) 419-427]</ref>. This experimental system has been also used to measure proton rotation using spectral line emission from excited fast neutrals created from inner core plasma protons via charge exchange transfer reactions. <ref>[http://link.aip.org/link/?RSINAK/74/2056/1 B. Zurro et al, ''Investigation of proton rotation measurements using hydrogen line wings in the TJ-II stellarator'', Rev. Sci. Instrum. '''74''' (2003) 2056]</ref>

A method for measuring absolutely calibrated toroidal rotation velocities consists of simultaneously recording the emission lines from the plasma and from a calibration lamp by means of a double fiber-fiber guide.