12.5	Cycle 18 Calibration Program

The Cycle 18 calibration program continued the calibration and monitoring observations performed in Cycle 17, including long-term programs to monitor the sensitivity and wavelength scale of both the NUV and FUV detectors. Brief descriptions of these programs are presented in Table 12.3. A comprehensive review of the Cycle 18 calibration program will be published in an upcoming ISR (Kriss et al. 2012).

Table 12.3: Cycle 18 Calibration Program

Program ID	Title	Accuracy Achieved	Products
NUV Monitors
12419	NUV MAMA Fold Distribution	< 5% in the location of the peak of the fold distribution	ISR
12420	NUV Detector Dark Monitor	< 0.2% in global dark rate uncertainty	ISR
12421	NUV Spectroscopic Sensitivity Monitor	S/N = 30 at λcen	ISR, Reference file
12422	NUV Internal/External Wavelength Scale Monitor	1.7–3.7 pixels in wavelength scale accuracy	ISR, Reference file
FUV Monitors
12423	FUV Detector Dark Monitor	Rate < 10−6 counts/pixel/s. 0.1% in global dark rate uncertainty	ISR
12424	FUV Spectroscopic Sensitivity Monitor	S/N = 30 at λcen	ISR, Reference file
12425	FUV Internal/External Wavelength Scale Monitor	Wavelength zero-point accuracy: 5.7–7.5 pix for G130M, 5.8–7.2 pix for G160M, 7.5–12.5 pix for G140L	ISR, Reference file
Special Programs
None1	COS Observations of Geocoronal Lyman α Emission	G140L: S/N = 2 per pixel at 1200 Å, G130M: S/N = 2 per pixel at 1213 Å	List of exposures on the COS Web site that GOs may use to model and subtract Lyman α
12426	FUV Sensitivity Characterization	S/N ~ 10/pixel	ISR, Reference file
12432	COS FUV Detector Gain Sag vs. High Voltage	1% over 2 Å bands	Decision on change of voltage or lifetime position

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1

Coordinated parallel with a STIS calibration program.