Performance of the Imaging Fourier Transform Spectrometer with Photoconductive Detector Arrays: An Application for the AKARI Far-Infrared Instrument

TL;DR

This paper discusses the development and successful space-based operation of an imaging Fourier transform spectrometer with photoconductive detectors on the AKARI satellite, highlighting its performance, data collection, and challenges like detector transient effects.

Contribution

It introduces a novel space-based FTS utilizing photoconductive detector arrays with a capacitive trans-impedance amplifier, demonstrating its effective operation in space.

Findings

Performed over 600 observations totaling 100 hours of data

The FTS performed well, producing valuable astronomical data

Detector transient effects significantly impact FTS performance

Abstract

We have developed an imaging Fourier transform spectrometer (FTS) for space-based far-infrared astronomical observations. The FTS employs a newly developed photoconductive detector arrays with a capacitive trans-impedance amplifier, which makes the FTS a completely unique instrument. The FTS was installed as a function of the far-infrared instrument (FIS: Far-Infrared Surveyor) on the Japanese astronomical satellite, AKARI, which was launched on February 21, 2006 (UT) from the Uchinoura Space Center. The FIS-FTS had been operated for more than one year before liquid helium ran out on August 26, 2007. The FIS-FTS was operated nearly six hundreds times, which corresponds to more than one hundred hours of astronomical observations and almost the same amount of time for calibrations. As expected from laboratory measurements, the FIS-FTS performed well and has produced a large set of astronomical data for valuable objects. Meanwhile, it becomes clear that the detector transient effect is a considerable factor for FTSs with photoconductive detectors. In this paper, the instrumentation of the FIS-FTS and interesting phenomena related to FTS using photoconductive detectors are described, and future applications of this kind of FTS system are discussed.