A meta-analysis of molecular spectroscopy databases, and prospects of molecule detection with some future facilities

TL;DR

This paper conducts a meta-analysis of molecular spectroscopy databases, evaluates current limitations, and explores future prospects for detecting complex molecules in space with upcoming observational facilities.

Contribution

It systematically analyzes the CDMS and JPL databases, discusses line confusion issues, and assesses future detection capabilities with new telescopes.

Findings

Potential detection of complex organic molecules with future facilities

Line confusion limits in certain physical environments

CSST/HSTDM and SKA1-mid could detect amino acids

Abstract

Molecules reside broadly in the interstellar space and can be detected via spectroscopic observations. To date, more than 271 molecular species have been identified in interstellar medium or circumstellar envelopes. Molecular spectroscopic parameters measured in laboratory make the identification of new species and derivation of physical parameters possible. These spectroscopic parameters are systematically collected into databases, two of the most commonly used being the CDMS and JPL databases. While new spectroscopic parameters are continuously measured/calculated and added to those databases, at any point in time it is the existing spectroscopic data that ultimately limits what molecules can possibly be identified in astronomical data. In this work, we conduct a meta-analysis of the CDMS and JPL databases. We show the statistics of transition frequencies and their uncertainties in these two databases, and discuss the line confusion problem under certain physical environments. We then assess the prospects of detecting molecules in common ISM environments using a few facilities that are expected to be conducting spectroscopic observations in the future. Results show that CSST/HSTDM and SKA1-mid have the potential to detect some complex organic molecules, or even amino acids, with reasonable assumptions about ISM environments.