Cygnus X-3

Located 37, 000 light years away in the constellation Cygnus, which straddles the galactic plane, is a powerful x-ray source named Cygnus X-3. Although it is only the third brightest x-ray source in the constellation after the famous Cygnus X-1, it is much further away on the far side of the galaxy and is obscured by intervening interstellar gas and dust near the galactic plane. When this is factored in, it appears to be one of the two or three most luminous objects in the galaxy in intrinsic brightness. It has received attention because it is one of the few sources of ultra-high energy cosmic rays with energies in the 100 - 1000 TeV range. But its most unique aspect is the production of anomalous cosmic ray events in a proton decay detector deep in Minnesota's Soudran iron mine. These events have defied analysis and have led to questions about whether Cygnus X-3 is a standard neutron star or perhaps something more exotic, like a star made of quarks. Cygnus X-3 is a compact object in a binary system which is pulling in a stream of gas from an ordinary star companion.

Cygnus X-3 has distinguished itself by its intense X-ray emissions and by ultrahigh energy cosmic rays. It also made astronomical headlines by a radio frequency outburst in September 1972 which increased its radio frequency emissions a thousandfold. Since then it has had periodic radio outbursts with a regular period of 367 days. These flares are of unknown origin, but they are exceedingly violent events. Naval Research Laboratory observations in October 1982 using the Very Large Array detected the shock wave from a flare; it was expanding at roughly one-third the speed of light.

Cygnus X-3 has an orbital period about its companion of only 4.79 hours. Intriquing underground events in the Soudron iron mines in October 1985 included 60 anomalous muon events in a 3¡ cone around Cygnus X-3 with a precise period of 4.79 hours, so they clearly came from that source. But that requires a neutral particle traveling at almost precisely the speed of light, and there are no reasonable candidates for such a particle.

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Cygnus X-3 Cosmic Rays

Deep in the caverns of the Soudron iron mines are massive detectors designed to measure proton decay. They also measure some background cosmic ray events which can penetrate the thick layer of rock above the detector. Out of 1200 such events measured in a period during October 1985 were 60 anomalous muon events in a 3¡ cone around Cygnus X-3 with a precise period of 4.79 hours, so they clearly came from that source. Cygnus X-3 has an orbital period about its companion of only 4.79 hours.

But no known particles can produce such events! Muons themselves are too short-lived to have traveled 37,000 light years so they must be secondary. The particles must be neutral to arrive with that precise directionality. They must be traveling at the same speed, essentially the speed of light, and there are no reasonable candidates for such a particle. The possibilities are neutrinos, photons, and high energy neutrons. Neutrinos are ruled out by the loss of the signal at the horizon, the photon flux is 300 times too small, and neutrons are unstable and wouldn't survive the trip.

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