21 July 2010 Measuring the effective wavelength of CHARA classic
Author Affiliations +
Abstract
This paper presents the first empirical measurement of the K1-band effective wavelength and bandwidth of the CHARA Classic beam combiner on the CHARA Array. Prior to this work, the accepted effective wavelength value used for CHARA Classic data (2.1501μm) came from a model of the system; it was not derived from measurements done on the system directly. We employ two data collection methods for our observations: using the Optical Path Length Equalizer (OPLE) cart to scan through the interference fringes and using the dither mirror to scan through the fringes. The two observational methods yield similar effective wavelength measurements (2.141±0.003μm with the OPLE cart and 2.136±0.002μm with the dither mirror). Both of these results are lower than the previously adopted effective wavelength value, but by less than 0.7%. The bandwidth values measured by the two methods differ from each other by almost 5% (0.334 ± 0.002μm with the OPLE cart and 0.351±0.003μm with the dither mirror). Our results establish the first estimate of the uncertainty in the effective wavelength and bandwidth.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Emily C. Bowsher, Emily C. Bowsher, Harold A. McAlister, Harold A. McAlister, Theo A. ten Brummelaar, Theo A. ten Brummelaar, } "Measuring the effective wavelength of CHARA classic", Proc. SPIE 7734, Optical and Infrared Interferometry II, 77342W (21 July 2010); doi: 10.1117/12.856141; https://doi.org/10.1117/12.856141
PROCEEDINGS
15 PAGES


SHARE
RELATED CONTENT


Back to Top