Announcements
Baseline Calibrations
The baseline calibrations for IGRINS-2 include Telluric standards, flatfields, and zenith sky observations. The required Night Basecal Time per observation is automatically calculated by the PIT and already includes the time needed for the standard telluric observations.
The following baseline calibrations are shared by all IGRINS-2 programs observed during a given night. Applicants should not include time for these baseline calibrations in their Phase I proposals:
- Flats are taken daily as part of the daytime calibration
- Sky emission line observations for wavelength calibration are taken as nighttime partner calibrations.
If additional calibrations are deemed necessary by applicants, they must be explicitly included as part of the Phase I proposal and Phase II science program. No spectrophotometric standards or specific radial velocity (RV) standards are observed as part of the baseline calibration. Any time required for additional calibrations between the hours of nautical sunset and sunrise will be charged to the respective program.
Further information on near-IR calibration, including line lists, standard star search tools, and spectral template libraries, can be found on the Gemini NIR resources pages.
| Measurement Type | Notes |
| Flat fields | Flat-field calibration frames will be obtained using the facility calibration unit, GCAL, as part of daytime baseline calibration. These frames include shutter-open (lamp on) and shutter-closed (lamp off) exposures to correct for thermal emission, dark current, and hot pixels. The typical exposure time is 30 seconds. |
| Wavelength calibration | The main wavelength calibrator for IGRINS-2 is the sky emission lines. A zenith sky frame will be taken every night when IGRINS-2 is scheduled for observations as a nighttime partner calibration, shared by all IGRINS-2 programs. The typical exposure time is 300 seconds. |
| Telluric standard star | Telluric standard stars will be observed as part of the nighttime partner calibrations. A telluric standard will be observed for every 1.5 hours of clock time spent on a science target. PIs should include two standards in each observation group; one suitable for observation before the science target, and another suitable for after the science target. For more information, please refer to our telluric standards page. |