| The relatively unexplored fast radio transient parameter space is known to be home to a variety of interesting sources, including pulsars, pulsar giant pulses and non-thermal emission from planetary magnetospheres. In addition, a variety of hypothesized but as-yet-unobserved phenomena, such as primordial black hole evaporation and prompt emission associated with coalescing massive objects have been suggested. In 2007, a bright 30-Jy radio pulse was detected (central point in the figure above), of apparently extragalactic origin. This discovery, its potential confirmation in 2011 (left point in the figure) and the subsequent consternation have demonstrated both the potential utility of bright radio pulses as probes of the interstellar medium and intergalactic medium, as well as the need for wide-field surveys characterizing the fast-transient parameter space.
In Siemion et al. 2011 (ApJ in press, arXiv:1109.2659) we now present results from the 450 hour, 150 deg2 Fly's Eye survey for bright dispersed radio pulses at the Allen Telescope Array (ATA). The Fly's Eye spectrometer produces 128 channel power spectra over a 209 MHz bandwidth, centered at 1430 MHz, on 44 independent signals paths originating with 30 independent ATA antennas. Data were dedispersed between 0 and 2000 pc cm-3 and searched for pulses with dispersion measures greater than 50 pc cm-3 between 625 μs and 5 s in duration. No pulses were detected in the survey, implying a limiting rate of less than 2 per hour over the sky, for any 10-millisecond duration pulses having apparent energy densities greater than 440 kJy μs, or mean flux densities greater than 44 Jy (the thick dashed line in the figure).