Vivek V Menon

The Eight-Meter-Wavelength Transient Array (ETA)

TitleThe Eight-Meter-Wavelength Transient Array (ETA)
Publication TypeConference Paper
Year of Publication2006
AuthorsJ. H. Simonetti, S. W. Ellingson, C. D. Patterson, W. Taylor, V. Venugopalan, S. Cutchin, and Z. Boor
Conference NameBulletin of the American Astronomical Society 207th Meeting
Date PublishedJanuary
Conference LocationWashington, DC

The Eight-meter-wavelength Transient Array (ETA) is a radio telescope utilizing a low-cost backend, which implements flexible, reconfigurable computing techniques. It is designed to continuously monitor nearly the entire northern sky at 29-47MHz in a search for low-frequency radio transients (short pulses) from high-energy astrophysical phenomena. This antenna array, which is currently under construction, is located in a relatively radio-quiet area in the Blue Ridge Mountains southwest of Asheville, NC, at the Pisgah Astronomical Research Institute (PARI). The array consists of 12 dual-polarization dipole antennas. The core of the array is 10 antenna stations arranged in a 16-m diameter circle with one antenna station at the center. In addition, one antenna station is situated about 50m to the north of the core and another is about 50m to the east of the core. A 26-m dish on the PARI site (about 1km from the ETA core) will be used for follow-up, added aperture, longer baselines, and additional radio frequency interference (RFI) mitigation. Preliminary observations with one test antenna station have detected the expected Galactic emission in this frequency range; ETA will be Galactic-noise limited. The ETA backend will utilize off-the-shelf components and a cluster of Field Programmable Gate Arrays (FPGAs) for detecting pulses of various lengths, dispersion measures, and directions (synthesized delay beams), while incorporating various RFI countermeasures. Potential sources of radio transients that might be observed by ETA include gamma-ray bursts (prompt emission), supernovae (prompt emission), coalescing compact-object binaries (e.g., neutron star – neutron star, neutron star – black hole), and exploding primordial black holes. This array should detect giant pulses from the Crab Pulsar, and possibly other pulsars. ETA is a collaboration of the Electrical and Computer Engineering Department and Physics Department at Virginia Tech, and PARI. ETA work at Virginia Tech is funded by an Advanced Techniques & Instrumentation (ATI) grant from the National Science Foundation.