TY - JOUR
T1 - A direct measurement of atmospheric dispersion in N-band spectra
T2 - Implications for mid-IR systems on ELTs
AU - Škemer, Andrew J.
AU - Hinz, Philip M.
AU - Hoffmann, William F.
AU - Close, Laird M.
AU - Kendrew, Sarah
AU - Mathar, Richard J.
AU - Stuik, Remko
AU - Greene, Thomas P.
AU - Woodward, Charles E.
AU - Kelley, Michael S.
PY - 2009/8
Y1 - 2009/8
N2 - Adaptive optics will almost completely remove the effects of atmospheric turbulence at 10 //m on the Extremely Large Telescope (ELT) generation of telescopes. In this article, we observationally confirm that the next most important limitation to image quality is atmospheric dispersion, rather than telescope diffraction. By using the 6.5 m MMT with its unique mid-IR adaptive optics system, we measure atmospheric dispersion in the N band with the newly commissioned spectroscopic mode on MIRAC4-BLINC. Our results indicate that atmospheric dispersion is generally linear in the N band, although there is some residual curvature. We compare our measurements to theory, and make predictions for ELT Strehls and image FHWM with and without an atmospheric dispersion corrector (ADC). We find that for many mid-IR applications, an ADC will be necessary on ELTs.
AB - Adaptive optics will almost completely remove the effects of atmospheric turbulence at 10 //m on the Extremely Large Telescope (ELT) generation of telescopes. In this article, we observationally confirm that the next most important limitation to image quality is atmospheric dispersion, rather than telescope diffraction. By using the 6.5 m MMT with its unique mid-IR adaptive optics system, we measure atmospheric dispersion in the N band with the newly commissioned spectroscopic mode on MIRAC4-BLINC. Our results indicate that atmospheric dispersion is generally linear in the N band, although there is some residual curvature. We compare our measurements to theory, and make predictions for ELT Strehls and image FHWM with and without an atmospheric dispersion corrector (ADC). We find that for many mid-IR applications, an ADC will be necessary on ELTs.
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U2 - 10.1086/605312
DO - 10.1086/605312
M3 - Article
AN - SCOPUS:70349307315
SN - 0004-6280
VL - 121
SP - 897
EP - 904
JO - Publications of the Astronomical Society of the Pacific
JF - Publications of the Astronomical Society of the Pacific
IS - 882
ER -