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Spectroscopy: Grisms and Slits

Spectroscopy is done with the Large Field Objective (pixel scale ~ 0.29 arc / second), one of three slits and one of three grisms.

Long Slits

Slits (arcsec)

2 x 290

1 x 290

0.6 x 290

Table 1. SOFI slits.

Grisms

Grism \ Parameters	Order	Dispersion	Resolution (0.6" slit)	Wavelength Range
GB Grism Blue	1	6.96	1000	0.95-1.64
GR Grism Red	1	10.22	1000	1.53-2.52
HR Grism	3	4.63	2200	2.00-2.30
HR Grism	4	3.44	1500	1.49-1.81
HR Grism	5	2.71	1400	1.20-1.28
HR Grism	6	2.32	1400	1.17-1.24
HR Grism	7	1.87	1400	0.89-0.93
HR Grism	8	1.58	1400	0.86-0.95

Table 2. SOFI Spectroscopy modes.

Line Identification

Xenon Lamp with the Blue Grism (Postscript)
Xenon Lamp with the Red Grism (Postscript)
Neon and Xenon Lamps with the HR Grism in 3rd order (Ks) (Postscript)
Neon and Xenon Lamps with the HR Grism in 4th order (H) (Postscript)
Neon and Xenon Lamps with the HR Grism in 5th and 6th order (J) (Postscript)
Neon and Xenon Lamps with the HR Grism in 7th and 8th order (Z) (Postscript)
Xenon-Argon lines from 0.8 to 2.5 microns (from the ISAAC Manual)
OH Sky lines from 1.0 to 2.2 microns (from the ISAAC Manual)
New/updated Neon and Xenon arc line list. (Feb 2006)

Reccomended DIT/NDIT for Arcs and Flats

Arcs: DIT=5 sec, NDIT=10 (for both LR and MR)
Flats: DIT=2 sec, NDIT=30 (for both LR and MR)

Distortion maps for spectroscopy

Calibration data for distortion corrections, for all spectrosocpic modes (link to the new ftp site; last set of distortion calibrations from 2011-05-16).