Figure 4
Data for the indirect cryogenically cooled silicon crystal. Open circles denote points with I1 FWHM ≤ 2 arcsec, filled circles denote points with 2 arcsec < I1 FWHM ≤ 10 arcsec, filled squares denote points with 10 arcsec < I1 FWHM ≤ 20 arcsec, filled diamonds denote points with 20 arcsec < I1 FWHM ≤ 30 arcsec, and filled triangles denote points with I1 FWHM > 30 arcsec. The heavy dotted line is the `heat-load-tuning curve' (see text) and the thin solid line is a guide to the eye differentiating the `good' and `bad' performance regions. |