arXiv subjects

Soudan 2 Collaboration

Publications and source records attributed to Soudan 2 Collaboration.

3 recordsLinked to original sources

arXiv1999

Cosmic Ray Sun Shadow in Soudan 2 Underground Muon Flux

The absorption of cosmic rays by the sun produces a shadow at the earth. The angular offset and broadening of the shadow are determined by the magnitude and structure of the interplanetary magnetic field (IPMF) in the inner solar system. We report the first measurement of the solar cosmic ray shadow by detection of deep underground muon flux in observations made during the entire ten-year interval 1989 to 1998. The sun shadow varies significantly during this time, with a $3.3σ$ shadow observed during the years 1995 to 1998.

hep-ex↗

arXiv1999

Observation of the Moon Shadow in Deep Underground Muon Flux

A shadow of the moon, with a statistical significance of $5σ$, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with $σ\le 0.3^{\circ}$. The position of the shadow confirms the alignment of the detector to better than $0.15^{\circ}$. This alignment has remained stable during 10 years of data taking from 1989 through 1998.

hep-ex↗

arXiv1999

Cygnus X-3 Revisited: 10 Years of Muon and Radio Observations

The Soudan 2 deep underground tracking calorimeter has recorded cosmic ray muon tracks from the direction of the galactic x-ray binary Cygnus X-3 on most transits during the interval 1989-1998. We analyze these events in the context of previous reports of Cygnus X-3-related muon flux during major radio flares of that source. We find some evidence for excess flux during a small number of transits coincident with major radio flares. We also find an indication that these events may be distributed around the source with a Gaussian point spread function with $σ= 1.3^{\circ}$, larger than the instrumental angular spread of $\le 0.3^{\circ}$, verified by observation of the shadow of the moon.

hep-ex↗