Troubleshooting guide

Figure 4: Schematic of the UF 3pix long slit (left) and NOAO slit (right). The acquisition box for the
NOAO slit is 10 arcsec square at the 4-m. The two slits are each 60 arcsec long, centered 60 arcsec on
either side of the center of the mask.
The general outline for spectral observations is:
1. Set Instrument Position Angle (PA) to match the slit PA.
2. Verify telescope pointing on a SAO or Fixed Bright star close to target position.
3. Acquire target close to the long slit center or alignment aperture in MOS plate.
4. Check focus.
5. Acquire a guide star and start guiding.
6. Insert appropriate decker baffle (long slit or MOS) and check its alignment.
7. Insert and align long slit or MOS plate with target(s).
8. Insert desired filter and grism.
9. Set bias to 0.75 V for spectroscopy.
10.Configure spectral dither pattern parameters.
11.Execute spectral dither pattern.
12.Take all of the required quartz or dome flats, and HeNeAr wavelength calibration data if desired.
13.Repeat steps 1 – 14 with the long slit on a bright telluric standard star (G5-6 V) close by on the sky.
6
14.You may want to take a long slit spectrum of an A0 star at low airmass as well.
15.Take darks (10 - 20 each) at the exposure times used for sky wavelength calibrations. Darks are not
needed for the science target and standard spectroscopy if the source is dithered on the slit, or for dome
flats and HeNeAr calibrations taken using the "lamp on – lamp off" protocol. Be sure to use the
spectroscopy bias of 0.75 V. These may be done in the afternoon.
6 If you intend to use the 3-pixel MOSplate long slit, you can leave the decker positioned at the MOS baffle.
FLAMINGOS@4-m, Ver. 2.39, 2013 April 23 Page 24 of 47