1999/05/24 by Soudan Collaboration, Soudan 2 Collaboration
Computer Science · Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Computational Physics and Python Applications #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Solar and Space Plasma Dynamics #hep-ex
paper · pdf · doi:10.48550/arxiv.hep-ex/9905043
arxiv created 1999/05/24 · openalex publication_date 1999/05/24 · arxiv updated 2012/08/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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.