Las Campanas IMACS Raw Data Collection Overview

Data Abstract
=============
We obtained images of the (65803) Didymos system and supporting calibration 
images with the Inamori-Magellan Areal Camera and Spectrograph (IMACS) on 
the 6.5m Magellan-Baade Telescope at the Las Campanas Observatory (LCO). 
These images were taken in order to determine the orbit period of Dimorphos, 
the satellite of Didymos. This collection consists of the Las Campanas 
IMACS raw images, which include Didymos images and flat field images.

Data Set Overview
=================
IMACS is a reimaging spectrograph mounted permanently on the Magellan-
Baade Telescope. The f/2 camera provides a 27.4 arcmin diameter field at 
a scale of 0.200 arcsec per pixel across the CCD mosaic array employing 
eight thinned CCDs manufactured by E2V to produce a 8192 x 8192 pixel 
mosaic. These CCDs are all 2K x 4K x 15-micron devices. Each detector thus 
provides a ~6.8' x 13.6' FOV. Unbinned full frame readout for the arrays is 
~82 seconds, while 2x2 binning can reduce the readout to 29 seconds. A wide 
range of facility filters are available including the SDSS r' (also 
referred to as the "Sloan_r" filter) being deployed for this campaign.

FITS images obtained with IMACS are written as individual frames for each 
of the 8 IMACS detectors in the f/2 CCD array. FITS images produced for 
this archive only utilize one of the detectors: CCD02. Raw image data 
include Didymos images and flat fields, with an overscan region on images 
used for bias-level subtraction. Flat field sources include dome flat 
fields obtained by taking images of a pupil-mask screen illuminated by 
telescope-mounted lamps, and observations of the twilight sky. Dark current 
is typically very low when imaging with IMACS, so dark frames are not used. 
Sidereal tracking was used and Didymos was allowed to move across the 
field.

Naming Convention
=================
Raw images consist of a single fits file containing the raw image and an 
associated XML file. They are named according to the following convention.

ift<counter>c<CCD#>_<yymmdd>.<ext>

where:
ift is the camera reference, referring to the IMACS f/2 camera

<counter> is a four-digit image counter for observing session starting 
at 0001, reset for each night of observation

c<CCD#>	is the CCD number (1-8) within the mosaic array for the IMACS focal 
plane. For this dataset, only CCD 2 was used so it is always 2.

<yymmdd> is the UTC year, month, day of observation

<ext> is the file extension. “.fits” for FITS file format, ".xml" for the 
PDS4 XML label

Ex. ift1001c2_220702.fits is a raw image product for a 2022-07-02 observing 
session. It is the 1001st image generated on that UT date.