Slow-scan Observations with the Infrared Camera (IRC) on-board AKARI

TL;DR

This paper details the calibration and data reduction methods for the slow-scan mode of AKARI's Infrared Camera, improving positional accuracy and flux calibration at 9 and 18 micrometers.

Contribution

It introduces a new data reduction toolkit and a self-pointing reconstruction method for enhanced accuracy in AKARI IRC slow-scan observations.

Findings

Positional accuracy improved to 1 arcsecond.

Point spread functions are approximately 6-7 arcseconds.

Flux calibration uncertainties are under 20%.

Abstract

We present the characterization and calibration of the slow-scan observation mode of the Infrared Camera (IRC) on-board AKARI. The IRC slow-scan observations were operated at the S9W (9 $\mu$m) and L18W (18 $\mu$m) bands. We have developed a toolkit for data reduction of the IRC slow-scan observations. We introduced a "self-pointing reconstruction" method to improve the positional accuracy to as good as 1". The sizes of the point spread functions were derived to be $\sim6"$ at the S9W band and $\sim7"$ at the L18W bands in full width at half maximum. The flux calibrations were achieved with the observations of 3 and 4 infrared standard stars at the S9W and L18W bands, respectively. The flux uncertainties are estimated to be better than 20% from comparisons with the AKARI IRC PSC and the WISE preliminary catalog.