MeerKAT

Abstract:

The identification, and subsequent discovery, of fast radio transients through blind-search surveys requires a large amount of processing power, in worst cases scaling as $\mathcal{O}(N^3)$. For this reason, survey data are generally processed offline, using high-performance computing architectures or hardware-based designs. In recent years, graphics processing units have been extensively used for numerical analysis and scientific simulations, especially after the introduction of new high-level application programming interfaces. Here we show how GPUs can be used for fast transient discovery in real-time. We present a solution to the problem of de-dispersion, providing performance comparisons with a typical computing machine and traditional pulsar processing software. We describe the architecture of a real-time, GPU-based transient search machine. In terms of performance, our GPU solution provides a speed-up factor of between 50 and 200, depending on the parameters of the search.

Abstract:

In this Letter we discuss the recently discovered radio transient in the nuclear region of M82. It has been suggested that this source is an X-ray binary, which, given the radio flux density, would require an X-ray luminosity,LX~ 6 × 1042ergs-1 if it were a stellar mass black hole that followed established empirical relations for X-ray binaries. The source is not detected in the analysis of the X-ray archival data. Using a 99 per cent confidence level upper limit we find thatLX≤ 1.8 × 1037and 1.5 × 1037ergs-1, using power law and disc blackbody models, respectively. The source is thus unlikely to be a traditional microquasar, but could be a system similar to SS433, a Galactic microquasar with a high ratio of radio to X-ray luminosity. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.