Status of the UC-Berkeley SETI Efforts

摘要

We summarize radio and optical SETI programs based at the University of California, Berkeley. The SEVENDIP optical pulse search looks for ns time scale pulses at visible wavelengths. It utilizes an automated 30 inch telescope, three ultra fast photo multiplier tubes and a coincidence detector. The target list includes F, G, K and M stars, globular cluster and galaxies.The ongoing SERENDIP V.v sky survey searches for radio signals at the 300 meter Arecibo Observatory. The currently installed configuration supports 128 million channels over a 200 MHz bandwidth with M.6 Hz spectral resolution. Frequency stepping allows the spectrometer to cover the full 300MHz band of the Arecibo L-band receivers. The final configuration will allow data from all 14 receivers in the Arecibo L-band Focal Array to be monitored simultaneously with over 1.8 billion channels.SETI@home uses the desktop computers of volunteers to analyze over 160 TB of data at taken at Arecibo. Over 6 million volunteers have run SETI@home during its 10 year history. The SETI@home sky survey is 10 times more sensitive than SERENDIP V.v but it covers only a 2.5 MHz band, centered on 1420 MHz. SETI@home searches a much wider parameter space, including 14 octaves of signal bandwidth and 15 octaves of pulse period with Doppler drift corrections from -100 Hz/s to +100 Hz/s. SETI@home is being expanded to analyze data collected during observations of Kepler objects of interest in May 2011.The Astropulse project is the first SETI search for μs time scale pulses in the radio spectrum. Because short pulses are dispersed by the interstellar medium, and the amount of dispersion is unknown, Astropulse must search through 30,000 possible dispersions. Substantial computing power is required to conduct this search, so the project uses volunteers and their personal computers to carry out the computation (using distributed computing similar to SETl@home).