Download presentation
Presentation is loading. Please wait.
1
Transient SETI Dan Werthimer University of California, Berkeley http://seti.berkeley.edu/
2
University of California, Berkeley SETI Program Graduate StudentsGraduate Students Chen Chang, Pierre Droz, Aaron Parsons, David Purdy Chen Chang, Pierre Droz, Aaron Parsons, David Purdy Undergraduate StudentsUndergraduate Students Daniel Chapman, Henry Chen, Charlie Conroy, Wonsop Sim Daniel Chapman, Henry Chen, Charlie Conroy, Wonsop Sim Astronomers, Computer Scientists and Engrs.Astronomers, Computer Scientists and Engrs. David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric Korpela, Matt Lebofsky, Jeff Mock, Rom Walton, Dan Werthimer David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric Korpela, Matt Lebofsky, Jeff Mock, Rom Walton, Dan Werthimer
3
Early Transient Transmitters
5
NOT FUNDED
9
Porno in space: FUNDED!
12
UC Berkeley SETI Programs Name Time Scale Search Type SERENDIPseconds radio sky survey SETI@home mS - seconds radio sky survey Astropulse nS - mS radio sky survey SEVENDIPnS visible targetted SPOCK 1000 seconds visible targetted DYSON IR targetted
13
AstroPulse Arecibo Sky surveyArecibo Sky survey –Covers decs 0 to 30, each beam 5 times –1420 MHz, 2.5 MHz bandwidth –7 years of data recorded so far (70 TB) Good time resolutionGood time resolution –Sensitive to 0.4 µs radio pulses at 21 cm DM rangeDM range –-1000 to +1000 pc/cm 3 SensitivitySensitivity –10 -18 W/m 2 peak (Coherent de-dispersion)
14
AstroPulse Only ~1.5 searches for single pulses on µs timescale before (O’Sullivan, Phinney)Only ~1.5 searches for single pulses on µs timescale before (O’Sullivan, Phinney) Pulsar searches: ms time scales, foldedPulsar searches: ms time scales, folded SETI@home: 0.8 ms single pulses.SETI@home: 0.8 ms single pulses. Potential astrophysics as well as SETIPotential astrophysics as well as SETI evaporating primordial black holes?evaporating primordial black holes? (Hawking, Rees, Ekers) (Hawking, Rees, Ekers) –Pulsars, Other astrophysical exotica?
18
Piggyback ALFA Sky Survey Improved sensitivityImproved sensitivity –Tsys, integration time Uniform sky samplingUniform sky sampling –galactic plane concentration Multibeam RFI rejectionMultibeam RFI rejection Larger BandwidthLarger Bandwidth
19
Pulsed vs. CW Concentrating power into short bursts can be more efficient than a “constantly on” transmitter. Pulsed signals can be easier to see above background noise.
20
Dispersion Coherent De-dispersion -1000 < DM < +1000 Requires lots of Computing!!!
21
AstroPulse Testing Sample batch of data run through shows expected noise characteristics, and little else … … so (hopefully) little RFI contamination for this type of signal.
22
BOINC Berkeley Open Infrastructure for Network ComputingBerkeley Open Infrastructure for Network Computing –General-purpose distributed computing framework. –Open source. –Will make distributed computing accessible to those who need it. (Starting from scratch is hard!)
23
Projects AstronomyAstronomy –SETI@home (Berkeley) –Astropulse (Berkeley) –Einstein@home: gravitational pulsar search (Caltech,…) –PlanetQuest (SETI Institute) –Stardust@home (Berkeley, Univ. Washinton,…) Earth scienceEarth science –Climateprediction.net (Oxford) Biology/MedicineBiology/Medicine –Folding@home, Predictor@home (Stanford, Scripts) –FightAIDSathome: virtual drug discovery PhysicsPhysics –LHC@home (Cern) OtherOther –Web indexing/search –Internet Resource mapping (UC Berkeley)
27
SETI@home Statistics TOTAL RATE
28
Optical SETI Pulse Search 1961 Charlie Townes Paper largely ingored until 1999 largely ingored until 1999 1971 Cyclops report calculates radio >> optical Today’s lasers can communicate across galaxy
29
Optical SETI Uses Leuschner Observatory (UCB)Uses Leuschner Observatory (UCB) –Automated 0.8m telescope Targeted SearchTargeted Search –Nearby F,G,K,M stars –~10,000 stars observed so far –100 galaxies
30
OSETI Detector 3-Photomultiplier fast coincidence detector –Sensitive to 1ns pulses Low background –False alarm rate: 1 per 300 hours (10 -6 Hz) –Double false alarm rate: 1 per 600 years! Good sensitivity –10 -8 W/m 2 peak –10 -19 W/m 2 average
32
Transient Instrumentation
36
Compute Module Diagram
37
19” 48RU Rack Cabin Capacity 40 compute nodes in 5 chassis (8U) per rack40 compute nodes in 5 chassis (8U) per rack Up to 16 trillion CMac/s performance per rackUp to 16 trillion CMac/s performance per rack 250 Watt AC/DC power supply to each blade250 Watt AC/DC power supply to each blade 12.5 Kwatt total power consumption12.5 Kwatt total power consumption Hardware cost: ~ $1MHardware cost: ~ $1M
38
Global Interconnects Commercial Infiniband switch from Mellanox, Voltaire, etc.Commercial Infiniband switch from Mellanox, Voltaire, etc. –Packet switched, non- blocking –24 ~ 144 ports (4X) per chassis –Up to 10,000 ports in a system –200~1000 ns switch latency –400~1200 ns FPGA to FPGA latency –480Gbps ~ 2.88Tbps full duplex constant cross section bandwidth –<$400 per port
39
Unified Digital Processing Architecture Distributed per antenna spectral channel processing Multiple reconfigurable backend application processing Commercial packet switched interconnect Backend data pulling through remote DMA access
40
Moore’s Law in FPGA world 100X More efficient than micro-processors! 3X improvement per year!
42
Future Spectrometers
43
Why you might not want to collaborate with us on Transient Observations
49
Seti Haiku
50
Searching for life Answers are revealed About ourselves Paula Cook, Duke University
51
One million earthlings Bounded by optimism Leave their PC’s on Dan Seidner
52
The SETI@home Client
59
Triplets Three evenly spaced spikes above 7.75X the mean power. (5.3X10 -25 W/m 2 )Three evenly spaced spikes above 7.75X the mean power. (5.3X10 -25 W/m 2 )
60
Pulses Modified Fast folding algorithm w/ dynamic thresholdModified Fast folding algorithm w/ dynamic threshold Logarithmically spaced periods from 3ms to 35sLogarithmically spaced periods from 3ms to 35s Sensitivity as low as 10 -26 J/m 2Sensitivity as low as 10 -26 J/m 2
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.