407 research outputs found
Setiburst: A Robotic, Commensal, Realtime Multi-Science Backend For The Arecibo Telescope
Radio astronomy has traditionally depended on observatories allocating time to observers for exclusive use of their telescopes. The disadvantage of this scheme is that the data thus collected is rarely used for other astronomy applications, and in many cases, is unsuitable. For example, properly calibrated pulsar search data can, with some reduction, be used for spectral line surveys. A backend that supports plugging in multiple applications to a telescope to perform commensal data analysis will vastly increase the science throughput of the facility. In this paper, we presen
A 4-8 GHz Galactic Center Search for Periodic Technosignatures
Radio searches for extraterrestrial intelligence have mainly targeted the
discovery of narrowband continuous-wave beacons and artificially dispersed
broadband bursts. Periodic pulse trains, in comparison to the above
technosignature morphologies, offer an energetically efficient means of
interstellar transmission. A rotating beacon at the Galactic Center (GC), in
particular, would be highly advantageous for galaxy-wide communications. Here,
we present blipss, a CPU-based open-source software that uses a fast folding
algorithm (FFA) to uncover channel-wide periodic signals in radio dynamic
spectra. Running blipss on 4.5 hours of 4-8 GHz data gathered with the Robert
C. Byrd Green Bank Telescope, we searched the central 6' of our Galaxy for
kHz-wide signals with periods between 11-100 s and duty cycles ()
between 10-50%. Our searches, to our knowledge, constitute the first FFA
exploration for periodic alien technosignatures. We report a non-detection of
channel-wide periodic signals in our data. Thus, we constrain the abundance of
4-8 GHz extraterrestrial transmitters of kHz-wide periodic pulsed signals to
fewer than one in about 600,000 stars at the GC above a 7 equivalent
isotropic radiated power of W at . From an astrophysics standpoint, blipss, with its utilization of a
per-channel FFA, can enable the discovery of signals with exotic radio
frequency sweeps departing from the standard cold plasma dispersion law.Comment: 20 pages, 11 figures, published in AJ, in press
(http://seti.berkeley.edu/blipss/
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