Nitric Oxide and other molecules: Molecular Modelling and Low FrequencyExploration using the Murchison Widefield Array

TL;DR

This study enhances molecular modelling of nitric oxide isotopologues and conducts a deep low-frequency radio survey with the MWA, setting important limits and informing future SKA observations.

Contribution

It provides new molecular models for 14NO and 15NO and performs a more extensive low-frequency survey, improving data processing insights for future radio astronomy.

Findings

No new molecular lines detected at current sensitivity.

Survey used four times more data and better resolution than previous studies.

Sets limits for future low-frequency molecular line searches.

Abstract

We present new molecular modelling for 14NO and 15NO and a deep, blind molecular line survey at low radio frequencies (99-129 MHz). This survey is the third in a series completed with the Murchison Widefield Array (MWA), but in comparison with the previous surveys, uses four times more data (17 hours vs. 4 hours) and is three times better in angular resolution (1' vs. 3'). The new molecular modelling for nitric oxide and its main isotopologue has seven transitions within the MWA frequency band (although we also present the higher frequency transitions). Although we did not detect any new molecular lines at a limit of 0.21 Jy beam^-1, this work is an important step in understanding the data processing challenges for the future Square Kilometre Array (SKA) and places solid limits on what is expected in the future of low-frequency surveys. The modelling can be utilised for future searches of nitric oxide.