2014/03/10 by Nathan Clarke, Larry R. D’Addario, Clarke, Nathan +5
Engineering · Physics and Astronomy · #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Particle accelerators and beam dynamics #Radio Astronomy Observations and Technology
paper · pdf · doi:10.48550/arxiv.1403.2468
openalex publication_date 2014/03/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Isolated, short dispersed pulses of radio emission of unknown origin have\nbeen reported and there is strong interest in wide-field, sensitive searches\nfor such events. To achieve high sensitivity, large collecting area is needed\nand dispersion due to the interstellar medium should be removed. To survey a\nlarge part of the sky in reasonable time, a telescope that forms multiple\nsimultaneous beams is desirable. We have developed a novel FPGA-based transient\nsearch engine that is suitable for these circumstances. It accepts\nshort-integration-time spectral power measurements from each beam of the\ntelescope, performs incoherent de-dispersion simultaneously for each of a wide\nrange of dispersion measure (DM) values, and automatically searches the\nde-dispersed time series for pulse-like events. If the telescope provides\nbuffering of the raw voltage samples of each beam, then our system can provide\ntrigger signals to allow data in those buffers to be saved when a tentative\ndetection occurs; this can be done with a latency of tens of ms, and only the\nbuffers for beams with detections need to be saved. In one version of our\nimplementation, intended for the ASKAP array of 36 antennas (currently under\nconstruction in Australia), 36 beams are simultaneously de-dispersed for 448\ndifferent DMs with an integration time of 1.0 ms. In the absence of such a\nmulti-beam telescope, we have built a second version that handles up to 6 beams\nat 0.1 ms integration time and 512 DMs. We have deployed and tested this at a\n34-m antenna of the Deep Space Network in Goldstone, California. A third\nversion that processes up to 6 beams at an integration time of 2.0 ms and 1,024\nDMs has been built and deployed at the Murchison Widefield Array telescope.\n