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A host of new low-frequency radio telescopes seek to measure the 21-cmtransition of neutral hydrogen from the early universe. These telescopes havethe potential to directly probe star and galaxy formation at redshifts $20\gtrsim z \gtrsim 7$, but are limited by the dynamic range they can achieveagainst foreground sources of low-frequency radio emission. Consequently, thereis a growing demand for modern, high-fidelity maps of the sky at frequenciesbelow 200 MHz for use in foreground modeling and removal. We describe a newwidefield imaging technique for drift-scanning interferometers,Tikhonov-regularized $m$-mode analysis imaging. This technique constructsimages of the entire sky in a single synthesis imaging step with exacttreatment of widefield effects. We describe how the CLEAN algorithm can beadapted to deconvolve maps generated by $m$-mode analysis imaging. Wedemonstrate Tikhonov-regularized $m$-mode analysis imaging using the OwensValley Long Wavelength Array (OVRO-LWA) by generating 8 new maps of the skynorth of $\delta=-30^\circ$ with 15 arcmin angular resolution, at frequenciesevenly spaced between 36.528 MHz and 73.152 MHz, and $\sim$800 mJy/beam thermalnoise. These maps are a 10-fold improvement in angular resolution over existingfull-sky maps at comparable frequencies, which have angular resolutions $\ge2^\circ$. Each map is constructed exclusively from interferometric observationsand does not represent the globally averaged sky brightness. Futureimprovements will incorporate total power radiometry, improved thermal noise,and improved angular resolution -- due to the planned expansion of the OVRO-LWAto 2.6 km baselines. These maps serve as a first step on the path to the use ofmore sophisticated foreground filters in 21-cm cosmology incorporating themeasured angular and frequency structure of all foreground contaminants.

The Radio Sky at Meter Wavelengths: m-Mode Analysis Imaging with the Owens Valley Long Wavelength Array