Over seven decades of solar microwave data obtained with Toyokawa and Nobeyama Radio Polarimeters

TL;DR

This paper reviews over seven decades of solar microwave flux and polarization data collected in Japan, highlighting the historical development, datasets, and public accessibility of the observations from Toyokawa and Nobeyama.

Contribution

It provides a comprehensive history and metadata overview of solar microwave observations in Japan, emphasizing data continuity and public data access.

Findings

Decades of solar microwave data are publicly available.

Historical progression of solar microwave monitoring in Japan.

Datasets include flux and polarization measurements from Toyokawa and Nobeyama.

Abstract

Monitoring observations of solar microwave fluxes and their polarization began in Japan during the 1950s at Toyokawa and Mitaka. At present (April 2022), monitoring observations continue with the Nobeyama Radio Polarimeters (NoRP) at the Nobeyama campus of the National Astronomical Observatory of Japan (NAOJ). In this paper, we present a brief history of the solar microwave monitoring observations preceding those now carried out by NoRP. We then review the solar microwave obtained at Toyokawa and Nobeyama and their metadata. The datasets are publicly provided by the Solar Data Archive System (SDAS) operated by the Astronomy Data Center of the NAOJ, via http (https://solar.nro.nao.ac.jp/norp/) and FTP (ftp://solar-pub.nao.ac.jp/pub/nsro/norp/) protocols.