Frequently Asked Questions related to CRIRES

•Do I need to submit OBs for telluric standard stars?


Answer: The CRIRES standard calibration plan does not include observations of telluric standard stars, so if you think you need telluric standard star observations you will need to prepare and submit OBs for these and the time to execute these observations will be charged to your programme. However, we strongly recommend to use the molecfit package, which can correct CRIRES spectra for telluric absorption using a model spectum of the earth's atmosphere, instead.


•I want to observe the same telluric star for all my science OBs. Is one telluric OB sufficient?


Answer: No. In service mode, no OB can be repeated. So you have to duplicate your telluric OB as many times as needed.


Is the (B-R) colour of the AO star really needed?


Answer: Yes. The (B-R) colour is mandatory for OBs in the AO mode. The AO works in the R-band whereas the observations are performed in the infrared. To correct for atmospheric refraction and to calculate the tip-tilt mirror orientation, one needs the B-R colour. Please provide this in the corresponding template.