Experimental Light Detectors and the Search for Extraterrestrial Intelligence.

By: Jermaine Martez TaylorCase Western Reserve Department of

Physics

PP

History of OSETI

•

• The search for extraterrestrial intelligence (SETI) has been ongoing since the publication of the seminal article by Cocconi and Morrison in 1959. For many years, searches for signals were performed only at radio wave- lengths despite the fact that searches at optical wavelengths had been suggested as early as 1961 (Schwartz and Townes), following the invention of the laser. However, spectacular improvements in laser technology over the last few decades have dramatically strengthened the case for optical searches. We can now imagine a laser system, built with presently known technology, that could produce detectable signals over distances to nearby stars. Arguments based on signal-to-noise, pulse dispersion, and energy budget considerations support the idea that laser pulses may be an for extraterrestrial intelligence’’ (OSETI) has emerged as an established sub-discipline of SETI.

Philip Morrison

Giuseppe Cocconi

!!!!!Idea!!!!!

•Many groups have taken a new approach in conducting searches for signals at Optical Wavelength instead of radio signals. The new ideas are motivated by the possibility that extraterrestrial civilizations might communicate over vast distances using short duration laser pulses which are measured in nanoseconds.

Lens experiment.

In This part of the Research I reconstructed a 13 year-old C code use

to calculate the pixels rather than do them by hand. The program was

also designed to calculate "best" cone placement, for real CCD images, that we would get from such an

experiment like the one’s conducted on the roof by HEA group.The program

Ran great with old experimental data. the

next step was getting the data from the test

conducted on roof and run with the new code.

Goals for Optical Telescope

Design an Optical Telescope that is capable of Detecting Optical laser pulses.

make a low cost system that can be operated from night-to-night in an nearly automated way with minimal operator involvement.

use a fixed-heading mirror system that will allow us to monitor particular declination region of the sky over a relatively long period of time. in this way, our telescope will be uniquely sensitive to any optical signals that arrive with low duty cycle.

Design

• To conduct OSETI requires an Optical Telescope together with one or more fast photo detectors called photomultipliers tubes (PMTs). The (PMTs) are placed in 3x3 rows at the focal point of each lens to record any rapid light flashes imaged by the surface of the lens at the Focal point of the lens. Our Experimental Design is designed with 11” X 11” Fresnel lens with a focal length of 87 cm. Our final design will be on a scale of 1.5 m X 1.04 m with a focal length of 1.4 m for each lens. There are to be a total of Nine lens in 3 rows of 3 or 3x3. Under each lens if we can place mini Telescope tubes to focus the photons from the focal point to the Pmt’s i think we will have not much more hits but direct hits, and stop interference of light from nearby lens.

Design Model

Lens

Photomultiplier Tube (PMT’s)

Wiring to connect PMT’sand transmit data

PMT’s

How it works

Optical Laser Signal

Top View

Atmospheric Cherenkov

Atmospheric Cherenkov light is associated with extensive air shower due to cosmic rays.Thousands are detected every year.

Background rejection and sensitivity.

?Questions?