Atmospheric extinction coefficients in the $\mathrm{I_c}$ band for several major international observatories: Results from the BiSON telescopes, 1984 to 2016

TL;DR

This study analyzes over 30 years of solar observation data from the BiSON network to determine atmospheric extinction coefficients in the I_c band across several major observatories worldwide.

Contribution

It provides a comprehensive long-term dataset of atmospheric extinction coefficients for major observatories, derived from solar data collected over three decades.

Findings

Extinction coefficients vary across different observatory sites.

Long-term stability or variability of atmospheric extinction coefficients is documented.

Data supports improved calibration for astronomical observations in the I_c band.

Abstract

Over 30 years of solar data have been acquired by the Birmingham Solar Oscillations Network (BiSON), an international network of telescopes used to study oscillations of the Sun. Five of the six BiSON telescopes are located at major observatories. The observational sites are, in order of increasing longitude: Mount Wilson (Hale) Observatory (MWO), California, USA; Las Campanas Observatory (LCO), Chile; Observatorio del Teide, Iza\~{n}a, Tenerife, Canary Islands; the South African Astronomical Observatory (SAAO), Sutherland, South Africa; Carnarvon, Western Australia; and the Paul Wild Observatory, Narrabri, New South Wales, Australia. The BiSON data may be used to measure atmospheric extinction coefficients in the $\mathrm{I_c}$ band (approximately 700-900 nm), and presented here are the derived atmospheric extinction coefficients from each site over the years 1984 to 2016.