X-Ray Induced Fluorescence Measurement of Segregation in a DyI3 Metal-Halide Lamp

Published

April 19, 2007

Author(s)

T Nimalisuriya, John J. Curry, Craig J. Sansonetti, E J. Ridderhof, S Shastri, A J. Flikweert, W W. Stoffels, M Haverlag, J J. van der Mullen

Abstract

X-ray induced fluorescence measurements, using high energy synchrotron radiation generated on the Sector 1 Insertion Device beamline at the Advanced Photon Source, were performed on a metal-halide lamp containing Hg and DyI$_3}$. Density distributions of Dy show significant axial and radial segregation. Density distributions of I show little axial and radial segregation, a surplus of I is formed in the discharge as Dy forms Dy silicates at the wall of the lamp burner. Axial segregation is quantified using the Fischer axial segregation parameter $\lambda$. For Dy $\lambda = 0.215 \pm 0.002$ mm$^-1}$, this is in agreement with $\lambda$ found with a laser absorptionmethod \citeFlikweert05}. The $\lambda$ value for Iodine was found to be four times smaller. From the Hg density distribution a temperature profile was constructed, using a wall temperature measurement for calibration.

Citation

Journal of Physics D-Applied Physics

Volume

40

Pub Type

Journals

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Keywords

dysprosium, lighting, plasma, spectroscopy, x-ray

Citation

Nimalisuriya, T. , Curry, J. , Sansonetti, C. , Ridderhof, E. , Shastri, S. , Flikweert, A. , Stoffels, W. , Haverlag, M. and van der Mullen, J. (2007), X-Ray Induced Fluorescence Measurement of Segregation in a DyI3 Metal-Halide Lamp, Journal of Physics D-Applied Physics, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=840863 (Accessed October 21, 2025)