We present a description of the Prototype All-Sky Imager ( PASI ) , a backend correlator and imager of the first station of the Long Wavelength Array ( LWA1 ) .
PASI cross-correlates a live stream of 260 dual-polarization dipole antennas of the LWA1 , creates all-sky images , and uploads them to the LWA-TV website in near real-time .
PASI has recorded over 13,000 hours of all-sky images at frequencies between 10 and 88 MHz creating opportunities for new research and discoveries .
We also report rate density and pulse energy density limits on transients at 38 , 52 , and 74 MHz , for pulse widths of 5 s. We limit transients at those frequencies with pulse energy densities of > 2.7 \times 10 ^ { -23 } , > 1.1 \times 10 ^ { -23 } , and > 2.8 \times 10 ^ { -23 } J m ^ { -2 } Hz ^ { -1 } to have rate densities < 1.2 \times 10 ^ { -4 } , < 5.6 \times 10 ^ { -4 } , and < 7.2 \times 10 ^ { -4 } yr ^ { -1 } deg ^ { -2 } .