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.

Table 12.3: Cycle 18 Calibration Program

Program ID	Title	Desired Accuracy	Products
NUV Monitors
12419	NUV MAMA Fold Distribution	< 5% in peak of fold distribution
12420	NUV Detector Dark Monitor	< 5%	ISR, Reference file
12421	NUV Spectroscopic Sensitivity Monitor	S/N = 30 at λcen	ISR, Reference file
12422	NUV Internal/External Wavelength Scale Monitor	Wavelength zero-point accuracy to a few pixels	ISR, Reference file
FUV Monitors
12423	FUV Detector Dark Monitor	few counts per exposure	ISR, Reference file
12424	FUV Spectroscopic Sensitivity Monitor	S/N = 30 at λcen	ISR, Reference file
12425	FUV Internal/External Wavelength Scale Monitor	Wavelength zero-point accuracy to a few pixels	ISR, Reference file
Special Programs
None1	COS Observations of Geocoronal Lyman α Emission	G140L: S/N =2 per pixel at 1200 е, G130M: S/N = 2 per pixel at 1213 е	List of exposures on the COS Web site that GOs may use to model and subtract Ly α
12426	FUV Sensitivity Characterization	1% over 2 е bands	ISR, Reference file
12432	COS FUV Detector Gain Sag vs. High Voltage	1% over 2 е bands	Decision on change of voltage or lifetime position

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1

Coordinated parallel with a STIS calibration program.