[ExI] SETI news

scerir scerir at libero.it
Fri Nov 21 19:43:38 UTC 2008


Berkeley conducts 7 SETI programs at IR, 
visible and radio wavelengths. Here we review 
two of the newest efforts, Astropulse and Fly's Eye.
A variety of possible sources of microsecond to 
millisecond radio pulses have been suggested in the 
last several decades, among them such exotic
events as evaporating primordial black holes, 
hyper-flares from neutron stars, emissions from 
cosmic strings or perhaps extraterrestrial
civilizations, but to-date few searches have 
been conducted capable of detecting them.
We are carrying out two searches in hopes of 
finding and characterizing these uS to mS time 
scale dispersed radio pulses. These two observing
programs are orthogonal in search space; the Allen 
Telescope Array's (ATA) "Fly's Eye" experiment observes 
a 100 square degree field by pointing each
6m ATA antenna in a different direction; by contrast, 
the Astropulse sky survey at Arecibo is extremely 
sensitive but has 1/3,000 of the instantaneous sky 
coverage. Astropulse's multibeam data is transferred via
the internet to the computers of millions of volunteers. 
These computers perform a coherent de-dispersion analysis 
faster than the fastest available supercomputers and 
allow us to resolve pulses as short as 400 nS. Overall,
the Astropulse survey will be 30 times more sensitive 
than the best previous searches. Analysis of results from 
Astropulse is at a very early stage. The Fly's Eye was 
successfully installed at the ATA in December of 2007, 
and to-date approximately 450 hours of observation has 
been performed. We have detected three pulsars and six 
giant pulses from the Crab pulsar in our diagnostic pointing 
data. We have not yet detected any other convincing
bursts of astronomical origin in our survey data.

More information about the extropy-chat mailing list