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X-Ray Absorption Imaging of Hg Vapor in a Ceramic Metal-Halide Lamp Using Synchrotron Radiation



John J. Curry, H G. Adler, A MacPhee, Suresh Narayanan, J C. Wang


The diagnostic technique based on absorption of x-rays by the Hg vapor in a high-intensity discharge lamp has been extended using synchrotron radiation as the source of x-rays and an intensified charge-coupled device (ICCD) as the detector. The high photon flux available from the synchrotron source and the electronic format of the ICCD have made time-resolved studies possible. Although no significant time-dependence was seen as a function of the electrical phase for an electronically ballasted lamp, real-time observations were made of the decaying Hg density during cool-down. The cold-spot temperature in a 150 W ceramic lamp containing Hg and rare-earth iodides decreased with a time constant of 48.4 s following arc extinction. The primary limitation to the sensitivity of these measurements has been identified and methods for overcoming thislimitation in future work are proposed. Other aspects of the technique are also discussed.
Plasma Sources Science & Technology


Hg vapor, lighting, metal-halide lamp, plasma diagnostic, synchrotron radiation, x-ray absorption, x-ray imaging, x-ray spectroscopy


Curry, J. , Adler, H. , MacPhee, A. , Narayanan, S. and Wang, J. (2004), X-Ray Absorption Imaging of Hg Vapor in a Ceramic Metal-Halide Lamp Using Synchrotron Radiation, Plasma Sources Science & Technology (Accessed July 22, 2024)


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Created May 1, 2004, Updated February 17, 2017