OVRO-LWA Solar Data Products

Introduction

THIS PAGE IS CURRENTLY UNDER CONSTRUCTION.

OVRO-LWA is an all-sky radio imager by design and hence in principle, can observe the Sun as long as it is above the horizon. However, the array is located in a valley surrounded by mountains, and hence the Sun is not visible from the array when its line-of-sight from the array passes through the mountains. Additionally at very low elevations, the performance of the array degrades significantly and the data gets increasingly affected by terrestrial radio emission. Keeping this in mind, the Sun is observed with the OVRO-LWA when the solar elevation is greater than approximately about 15 degrees. In summer this translates to about 7-14 hours of observations depending on the season. The highest time-frequency resolution at which data can be obtained with the OVRO-LWA in a regular manner is 1ms and 24 kHz respectively. However depending on the observation mode as well as due to data volume limitations, the actual available time-frequency resolution can vary. Figure 1 summarizes the different levels of data we produce. The later sections will give a more detailed description and usage examples. File:Ovro-lwa data products.pdf

Level 0 - Raw data from the instrument

OVRO-LWA, in general, operates multiple observing modes simultaneously. This is achieved by passing the raw data stream from the 352 antennas through multiple data handling processes, with each process handling an observation mode. The middle panel of Figure 1 (indicated as Level 0) shows the key parameters relevant for the solar data recorded by the different data streams.