Question 2) Continued

12

13,14 15

16

17

No

Have 32 channel spectrum analyzer and 1024 channel autocorrelator.

Planned: 1024 autocorrelator with minimum channel width of 200Hz

Planned: 50 channel 10kHz bandwidth filter.

Question 3)

Could astronomical research benefit from simultaneous multi-channel analyzers with 106 to 109 channels of lHz width? Comments?

6 For most spectroscopy 1kHz resolution is sufficient; the more channels the better.

7

106

-yes

109-don't know

14

15

Yes

Do not forsee uses for such high frequency
Possible, but expensive

16 No astronomical need for frequency resolution ≈ 100Hz.
17 100Hz seems to be smallest bandwidth useful for studies
of known natural processes.

Question 4)

Comment on the present state of the art of such systems. What characteristics would you require? How would you proceed to achieve them? What directions of development seem to you to offer most promise?

Question 4) Continued

Respondent

#1,2

3 Feasible, using autocorrelators

4

5

6

7,8,9

10

11

12

13

14

15

16

17

Achieve very narrow resolution through use of autocorrelation
spectrometer.

Autocorrelators or multifilters for 1-100mhz total coverage.
Acousto-optical or multifilter techniques for larger coverage.

Increase the usefulness of such a spectrometer if it could
be split into several parallel receivers.
Optical data most promising approach.

Working continuously on fine time resolution from weak
signals after removing interstellar dispersion.
Autocorrelator techniques to achieve such large capacity.
Problem with 106-109 multi channel analyzers is the drift
of the center of frequency of each channel; shouldn't
exceed 0.1 Hz.

For VLA spectral-line back end, a system is contemplated
which would have ~2x105 channels divided among the 351
interferometer pairs.

2 approaches

a) coherent optical processing method
b) Fast Fourier Transform algorithm.

Question 5)

If such an analyzer were made available to you would you
consider using it, via an IF tap or with spare receivers,
to "hitch a ride" for coherent signal search during normal
observing time?

Best to use antennas with large collecting area.
Possibly

Yes

Concerning technical improvements in pulsar observations: versatile very fast digital processing unit to perform the dispersion removal over wide bandwidths.

Yes

Have you ever engaged in any search for coherent or
"intelligent" signals at your facilities? If so, please
estimate the total hours used. Have the results been
reported? Was the search a by-product of other obser-
vations?

Explain.

17

3 searches:

No

a) OZMA/Drake

b) Verschuur

c) Palmer and Zuckerman (unpublished)

Search for electromagneitc pulses from the galactic center.

Yes

No

Yes; searching for narrow-band radiation near the hydrogen line.

11. THE SOVIET CETI REPORT

Researchers in the USSR have long been interested in the detection of radio signals originating from extraterrestrial intelligence. The Soviet have named their program CETI or Communication with Extraterrestrial Intelligence. The acronym SETI (Search for Extraterrestrial Intelligence) was adopted by the Workshop and by the Ames Research Center to differentiate our own efforts from those of the Soviet Union and to emphasize the search aspects of the proposed program.

The Soviet plans for their CETI efforts have been summarized in "The CETI Program," Sov. Astron., vol. 18, no. 5, March-April 1975, which has been reprinted here, in total, with permission of the American Institute of Physics, whose cooperation is gratefully acknowledged. This article was translated from "Scientific Council on the Radio-Astronomy Problem Area, Academy of Sciences of the USSR, Astron., Zh., 51, 1125-1132 (September-October 1974)."

The CETI program

Scientific Council on the Radio-Astronomy Problem Area, Academy of Sciences of the USSR
Astron., Zh., 51, 1125-1132 (September-October 1974)

In March 1974 the Board of the Scientific Council on the Radio Astronomy Problem Area, Academy of Sciences of the USSR, considered and approved a Research Program on the Problem of Communication with Extraterrestrial Civilizations. The Program was developed by the Search for Cosmic Signals of Artificial Origin section of the Council on Radio Astronomy, on the basis of recommendations made at the Soviet National Conference on the Problem of Communication with Extraterrestrial Civilizations held at the Byurakan Astrophysical Observatory in Armenia in May 1964, and the Soviet-American CETI conference held at Byurakan in September 1971. The projected program was reported to the 7th Soviet National Conference on Radio Astronomy, which convened at Gor'kii in 1972.

The program as outlined below is here published in detail with minor abridgments.

RESEARCH PROGRAM ON THE

PROBLEM OF COMMUNICATION

WITH EXTRATERRESTRIAL CIVILIZATIONS

PART I. INTRODUCTION

Formulation of the Problem

Principal Fields of Research on the Problem of Extraterrestrial Civilizations
Principles for Developing a CETI Program

1.

2.

3.

4.

Organizing Arrangements

PART II. SEARCH FOR COSMIC SIGNALS OF ARTIFICIAL ORIGIN

1.2. Selection of Sources by Angular Size and Investigation of Their Spatial Structure 1.3. Investigation of Selected Galactic and Extragalactic Objects

1.4. Search for Signals from Stars in the Immediate Solar Neighborhood

1.5. Search for Signals from Galaxies in the Local Group

1.6. Search for Signals with a Detection System Covering the Entire Sky

1.7. Search for Probes

1.8. Measurement of Cosmic Background Radiation in the Wavelength Range 20 μ- 1 mm

1.9. Investigation of Absorption and Phase Transparency of the Interstellar Medium in the Range 20 μ- 1 cm

1.10. Sky Surveys in the Range 10 μ- 1 mm

1.11. Search for Infrared Excesses in Stars of Suitable Spectral Type