4.1. Example 1 - Datasets description

4.1.1. Dithered Point Source XD with ShortBlue + 32 l/mm grating

In this example, we will reduce the GNIRS crossed-dispersed observation of a supernova type II 54 days after explosion.

This observation uses the 32 l/mm grating, the short-blue camera and the 0.675 arcsec slit. The dither pattern is the standard ABBA, repeated 5 times.

The calibrations we use for this example are:

  • BPM. The bad pixel masks are now found in the Gemini Observatory Archive instead of being packaged with the software. They are associated like the other calibrations. (The date in the name is the “valid from” date.)

  • Flats taken in the same configuration as the science. They were obtained at night right after the science observations. The flats are two series taken with two different lamps to ensure good exposure in each order. The software will combine them appropriately.

  • Pinholes taken in the same configuration as the science. They were obtained the morning after the science observations.

  • Arcs taken in the same configuration as the science and obtained at night at the end of the science observation sequences.

  • A telluric standard observation taken in the same configuration as the science and obtained at night, in this case, just before the science observation sequence, and at a similar airmass.

Warning

The Bad Pixel Masks (BPMs) are now found in the archive rather than packaged with the software. You must get the static BPM from the archive. See Get the BPMs in Tips and Tricks.

Here is the breakdown of the files. All the files are included in the tutorial data package. They can also be downloaded from the Gemini Observatory Archive (GOA).

Science

N20170113S0146-165

Science flats

N20170113S0168-183

Pinholes

N20170113S0569-573

Science arcs

N20170113S0166-167

Telluric

N20170113S0123-138

BPM

bpm_20121101_gnirs_gnirsn_11_full_1amp.fits