1.4 COS FAQ

Table 1.5: COS Frequently Asked Questions

QuestionAnswer

Should I use COS or STIS?
Does COS have an imaging mode?

Section 2.1
Chapter 6

What detectors are available?
What apertures?
What gratings? What are their properties?

Chapter 4
Section 3.1.2
Tables 5.1, 5.3, 5.4

What do COS images look like?
What do COS spectra look like?
Do the spectra have gaps?

Figure 6.1
Figures 4.3, 4.9
Section 5.5

What is the difference between ACCUM and TIME-TAG mode?
How do I estimate the BUFFER-TIME for TIME-TAG exposures?
How do I obtain wavelength-calibration exposures?

Section 5.2
Section 5.4
Section 5.7

What are the science impacts of the COS line-spread function?
What is the COS sensitivity and resolution below 1150 Å?
Which COS gratings suffer from second-order contamination?

How accurate is COS absolute/relative photometry?
How accurate are the COS wavelength scale and zero point?

Section 5.1.10
Section 5.1.11

How do I plan a successful target acquisition?

Chapter 8

What are the bright-object limits?
How do I confirm that my target/field is safe to observe?

Table 10.1
Section 10.5

How much time should I request for my observations?

Chapter 9

What are the current COS FUV detector lifetime positions?

Section 5.12