Is there "RFI" in Pulsed Optical SETI?
In the 40 year history of SETI, radio frequency interference (RFI) has proven to be the dominant background in microwave searches. As the SETI community broadens its electromagnetic scope and searches for optical beacons, it must characterize and identify backgrounds for pulsed optical SETI. We must ask the question: what is the "RFI" for pulsed optical SETI? This talk seeks to answer the question by examining the astrophysical, atmospheric, terrestrial, and instrumental sources of optical pulses of nanosecond timescale. Potential astrophysical/atmospheric sources include airglow and scattered zodiacal light, stellar photon pileup, muon events, and cosmic-ray induced Cerenkov flashes. Terrestrial sources, including lightning and laser communications, appear negligible. Instrumental backgrounds such as scintillation in detector optics and corona breakdown have been the dominant background in our experiments to date, and present significant design challenges for future optical SETI researchers.
SETI, interstellar communication, radio frequency interference.
Principal Author Affiliation
Physics Department, Harvard University
Principal Author Biography
Andrew Howard is a graduate student in Paul Horowitz's lab at Harvard University working on optical SETI. He has contributed to the Harvard group's current targeted search program which has searched over 3500 objects for nanosecond laser flashes. Andrew's current project (and Ph.D. thesis) is an all-sky survey for such signals.
Correspondence for Secondary Authors