Smithsonian Astrophysical Observatory
Harvard-Smithsonian Center for Astrophysics

CCD Noise Check R-port

Day 20061016

Test Conductor R. Kano

R. Kano, J. Cirtain, M. Weber, L. Lundquist

CCD Noise Check R-Port

This evening we successfully completed the first CCD noise check and re-enabled the CCD bakeout heaters. This marks the first time that XRT has taken exposures (albeit darks). Before disabling the CCD heater, the CCD temp was ~ 30 C. By the end of the pass, the heater and CCD temps had droped to about 20 C. Eight minutes later, on the next pass, we saw a CCD temp of -9 C. The noise check happened on the 3rd pass, about 90 minutes after heater disable. At that point, the CCD temp was below -37 C. The noise check was performed, and then we re-enabled the CCD heater on the same pass. The CCD temp was at -37 C when the pass ended shortly thereafter. We have not yet received an explanation for all of these plots (and there were others). Kano pointed out the plot in the upper right. "sbx-img8000" refers to the first dark we took. This is an unsummed "calibration" image, which has 2176x2112 pixels. ("Calibration" images include the margin of overclocked pixels on 3 sides of the CCD, 64 pixels wide.) The plot in the upper right indicates that the read-noise level through the Right CCD port is approximately 1 DN. --->