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We present a 324.5MHz image of the NOAO Bo\"otes field that was made usingVery Large Array (VLA) P-band observations. The image has a resolution of5.6x5.1arcsec, a radius of $2.05^\circ$ and a central noise of ~0.2mJy\beam.Both the resolution and noise of the image are an order of magnitude betterthan what was previously available at this frequency and will serve as avaluable addition to the already extensive multiwavelength data that areavailable for this field. The final source catalogue contains 1370 sources andhas a median 325 to 1400MHz spectral index of -0.72. Using a radiocolour-colour diagram of the unresolved sources in our catalogue, we identify33 megahertz peaked-spectrum (MPS) sources. Based on the turnover frequencylinear size relation for the gigahertz peaked-spectrum (GPS) and compactsteep-spectrum (CSS) sources, we expect that the MPS sources that are compacton scales of tens of milliarcseconds should be young radio loud active galacticnuclei at high (z>2) redshifts. Of the 33 MPS sources, we were able todetermine redshifts for 24, with an average redshift of 1.3. Given that five ofthe sources are at z>2, that the four faint sources for which we could not findredshifts are likely at even higher redshifts and that we could only selectsources that are compact on a scale of ~5arcsec, there is encouraging evidencethat the MPS method can be used to search for high-redshift sources.

Megahertz peaked-spectrum sources in the Bo\"otes field I - a route towards finding high-redshift AGN?