Modal Simulation Framework for the Design and Verification of Future Few-Mode Far-Infrared Spectrometers

TL;DR

This paper introduces a modal simulation framework to aid in designing and verifying future far-infrared spectrometers, addressing straylight sensitivity and calibration challenges in ultra-sensitive few-mode detectors.

Contribution

It presents a novel modal framework applied to Herschel-SPIRE, enabling improved design, verification, and calibration strategies for future far-infrared spectrometers.

Findings

The framework effectively models complex modal behavior.

It helps identify straylight effects on measurements.

Supports development of calibration strategies.

Abstract

Future far-infrared space missions require highly-sensitive spectroscopy as a primary diagnostics tool. However, these systems are sensitive to straylight, due to the ultra-sensitive few-mode detectors used, which affects the measurement and calibration of the spectrum, as revealed by the Herschel mission. To ensure that the science goals of future missions are met, the complex modal behaviour has to be understood, and appropriate verification and calibration strategies must be developed. We propose a modal framework to addresses these issues, using Herschel-SPIRE as a case study, and demonstrate how the technique can be used for the design and verification of spectrometers in future far-infrared missions.