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Time Variation of the Global Solar Magnetic Field Inferred from the Sun's Shadow as Seen in 10 TeV Cosmic Rays

Published online by Cambridge University Press:  08 February 2017

L.K. Ding ,
M. Nishizawa ,
T. Sasaki ,
Y.H. Tan ,
Y. Yamamoto ,
T. Yuda  and
The Other Members of the Tibet Asγ Collaboration
L.K. Ding
Affiliation:
Institute for High Energy Physics, Academia Sinica, Beijing, China
M. Nishizawa
Affiliation:
National Center for Science Information Systems, Tokyo 112, Japan
T. Sasaki
Affiliation:
Department of Physics, Konan University, 8 Okamoto, Kobe 658, Japan
Y.H. Tan
Affiliation:
Institute for High Energy Physics, Academia Sinica, Beijing, China
Y. Yamamoto
Affiliation:
Department of Physics, Konan University, 8 Okamoto, Kobe 658, Japan
T. Yuda
Affiliation:
Institute for Cosmic Ray Research, University of Tokyo, Tanashi, Tokyo 188, Japan

Extract

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Air shower arrays with high counting rates at high altitude provide a unique means for the study of the time dependence of the Sun's shadow as seen in cosmic rays (Amenomori et al. 1992). With the Tibet-I array, operated from 1990 to 1993 at Yangbajing (4300m), we detected for the first time the influence of the solar and interplanetary magnetic fields (IMF) on the Sun's shadow. In this experiment the Sun's shadow seen by 10 TeV cosmic rays was found at a position 0.°7 away from the position of the Sun. This large displacement is considered to be caused by IMF which changed considerably in 1990-1993, near maximum, and during the declining phase of solar activity (cycle 22). A new Tibet-II array, enlarged in 1994, with a seven times larger effective area than the Tibet-I, has been operating since 1995 and allows us to observe the Sun's shadow every 3-4 months. The solar activity, being in the most quiet phase now in 1995-1997, will return to more active phase in 1998. Here, we present some results obtained in 1996 with Tibet-II array.

Type
VII. The Solar Atmosphere
Information
Symposium - International Astronomical Union , Volume 185: New Eyes to See Inside the Sun and Stars , 1998 , pp. 465 - 466
Copyright
Copyright © Kluwer 1998 

References

Amenomori, M. et al. 1992, Phys. Rev. Lett., 69, 2468.CrossRefGoogle Scholar
Amenomori, M. et al. 1993, Phys. Rev., D47, 2675.Google Scholar
Amenomori, M. et al. 1994, ApJ, 415, L147.CrossRefGoogle Scholar
Amenomori, M. et al. 1996, ApJ, 464, 954.CrossRefGoogle Scholar
NASA 1997, National Space Science Data Center, (URL http://nssdc.gsfc.nasa.gov/omniweb/).Google Scholar
NOAA/USAF 1997, Space Environmental Information Center, Solar Geophysical Data, (URL http://www.ngdc.noaa.gov/stp/stp.html).Google Scholar