Announcements
Please find more on Baseline Calibrations on the NIR instruments resources.
Recommended GCAL configurations and Exp. Times for F2 calibrations:
Quartz Halogen flats and Ar Arcs
Note the following:
GCALflats
All GCALflats are taken with:
- GCALdiffuser=IR
- Calibration Lamp = IR greybody - high
Two type of flats are taken:
- Imaging flats
- Longslit / MOS flats
The following table shows the optimal configuration (exposure time and the GCAL internal ND filter) in order to achieve a ~17 kADU flat field for each filter used in imaging mode.
Filter | GCAL Filter | Calibration Shutter | Exp. Time (sec) |
J-low | ND4.0 | Open | 3 |
J-low | ND4.0 | Closed | 3 |
J | ND4.5 | Open | 60 |
J | ND4.5 | Closed | 60 |
H | ND4.5 | Open | 3 |
H | ND4.5 | Closed | 3 |
Ks | ND2.0 | Closed | 3 |
K-blue | ND2.0 | Open | 6 |
K-red | ND2.0 | Open | 6 |
The table below shows the optimal configuration (exposure time and GCAL internal ND filter) for every combination of Grism + filter + Sliit width in order to produce a reliable spectroscopic flat.
Grism + Filter | Slit width (pixel) | GCAL filter | Exp. Time (sec) | Plots |
JH (R1200) + JH | 1 | ND2.0 | 15 | |
JH (R1200) + JH | 2 | ND2.0 | 8 | plot |
JH (R1200)+ JH | 3 | ND2.0 | 5 | |
JH (R1200) + JH | 4 | ND2.0 | 4 | plot |
JH (R1200) + JH | 6 | ND2.0 | 3 | |
JH (R1200) + JH | 8 | ND2.0 | 2 | plot |
HK (R1200) + HK | 1 | ND4.5 | 90 | |
HK (R1200) + HK | 2 | ND4.5 | 90 | plot |
HK (R1200)+ HK | 3 | ND4.5 | 75 | |
HK (R1200) + HK | 4 | ND4.5 | 60 | plot |
HK (R1200) + HK | 6 | ND4.5 | 40 | |
HK (R1200) + HK | 8 | ND4.5 | 30 | plot |
R3000 + J-low | 1 | Clear | 56 | |
R3000 + J-low | 2 | Clear | 24 | |
R3000 + J-low | 3 | Clear | 16 | |
R3000 + J-low | 4 | Clear | 12 | |
R3000 + J-low | 6 | Clear | 9 | |
R3000 + J-low | 8 | Clear | 6 | |
R3000 + J | 1 | Clear | 10 | |
R3000 + J | 2 | Clear | 5 | |
R3000 + J | 3 | ND1.0 | 25 | |
R3000 + J | 4 | ND1.0 | 20 | |
R3000 + J | 6 | ND1.0 | 12 | |
R3000 + J | 8 | ND1.0 | 10 | |
R3000 + H | 1 | ND1.0 | 6 | |
R3000 + H | 2 | ND2.0 | 50 | plot |
R3000 + H | 3 | ND2.0 | 40 | |
R3000 + H | 4 | ND2.0 | 25 | |
R3000 + H | 6 | ND2.0 | 20 | |
R3000 + H | 8 | ND2.0 | 15 | |
R3000 + Ks | 1 | ND2.0 | 32 | |
R3000 + Ks | 2 | ND2.0 | 16 | plot |
R3000 + Ks | 3 | ND2.0 | 12 | |
R3000 + Ks | 4 | ND2.0 | 9 | |
R3000 + Ks | 6 | ND2.0 | 6 | |
R3000 + Ks | 8 | ND2.0 | 4 |
GCAL Ar Comparison Lamps
All arcs are taken with the following configuration of GCAL:
- GCALlamp=Ar
- GCALdiffuser=IR
- GCALfilter = NIR balance
- Calibration Shutter = Closed (refers to GCAL flat source)
Next table shows the optimal exposure time for each combination of Grism + Filter + Slit width in order to produce a reliable arc.
Grism + Filter | Slit width (pixel) | GCAL filter | Exp. Time (sec) |
JH (R1200) + JH | 1 | NIR balance | 32 |
JH (R1200) + JH | 2 | NIR balance | 18 |
JH (R1200)+ JH | 3 | NIR balance | 12 |
JH (R1200) + JH | 4 | NIR balance | 10 |
JH (R1200) + JH | 6 | NIR balance | 8 |
JH (R1200) + JH | 6 | NIR balance | 8 |
HK (R1200) + HK | 1 | NIR balance | 90 |
HK (R1200) + HK | 2 | NIR balance | 60 |
HK (R1200)+ HK | 3 | NIR balance | 45 |
HK (R1200) + HK | 4 | NIR balance | 40 |
HK (R1200) + HK | 6 | NIR balance | 30 |
HK (R1200) + HK | 8 | NIR balance | 20 |
R3000 + J-low | 1 | NIR balance | 90 |
R3000 + J-low | 2 | NIR balance | 90 |
R3000 + J-low | 3 | NIR balance | 90 |
R3000 + J-low | 4 | NIR balance | 90 |
R3000 + J-low | 6 | NIR balance | 90 |
R3000 + J-low | 8 | NIR balance | 60 |
R3000 + J | 1 | NIR balance | 60 |
R3000 + J | 2 | NIR balance | 60 |
R3000 + J | 3 | NIR balance | 30 |
R3000 + J | 4 | NIR balance | 30 |
R3000 + J | 6 | NIR balance | 15 |
R3000 + J | 8 | NIR balance | 15 |
R3000 + H | 1 | NIR balance | 180 |
R3000 + H | 2 | NIR balance | 180 |
R3000 + H | 3 | NIR balance | 180 |
R3000 + H | 4 | NIR balance | 80 |
R3000 + H | 6 | NIR balance | 80 |
R3000 + H | 8 | NIR balance | 80 |
R3000 + Ks | 1 | NIR balance | 180 |
R3000 + Ks | 2 | NIR balance | 180 |
R3000 + Ks | 3 | NIR balance | 180 |
R3000 + Ks | 4 | NIR balance | 80 |
R3000 + Ks | 6 | NIR balance | 80 |
R3000 + Ks | 8 | NIR balance | 80 |