Seminars

Lecturer: Urban Brändström
Date: 2014-01-09 10:30
Place: Aniara

Optical intercalibration efforts: Preliminary results from intercalibration workshops 2012-2013

Urban Brändström
IRF

Abstract
The first absolute calibration of an optical instrument for
measurements of the night-airglow was described by Rayleigh in 1930.
European optical intercalibration efforts began around the time of the
International Geophysical Year in 1957. Comprehensive documentation of
intercalibration workshops exists since about 1980. Since the optical
meeting in Lysebu 1985, the Lindau Calibration Photometer designed by
Lauche and Barke has been the main intercalibration instrument.
Several $^{14}mathrm{C}$-activated phosphor light-standards used
since the 1960s are still in use and provide a long time-series
connecting the intercalibration efforts over the years. By convention,
the so-called "Fritz Peak" source has been used as an international
standard for the Rayleigh unit. This convention has often been
questioned and therefore this source has recently been intercalibrated
with a number of more modern light-standards traceable to different
national bureaus of standards. Preliminary results from these
comparisons will be discussed together with an overview of the
ongoing work at the present intercalibration workshop.

Created 2013-10-03 10:44:41 by Uwe Raffalski
Last changed 2014-01-08 08:01:39 by Mats Holmström