Speaker
Kenichi Sakai
(NASA/GSFC/CRESST/UMBC)
Description
The spectra of low-energy cosmic-ray protons, helium nuclei and antiprotons have been measured by BESS in 11 high-latitude balloon flights between 1993 and 2007. The original BESS experiment flew 8 times over Lynn Lake, Canada and once from Fort Sumner, USA during the period of 1993 through 2002. The long duration balloon (LDB) flights over Antarctica were carried out in 2004 and 2007 with BESS-Polar instrument. These measurements span a range of Solar activity from before the previous Solar minimum through Solar maximum (Cycle 23) and the latest Solar minimum, as well as a Solar magnetic field reversal from positive to negative in 2000. Since the low-energy region of the cosmic radiation is most intensively affected by solar modulation, the absolute fluxes and spectral shapes of primary protons and helium obtained with BESS are essential probes. These are combined with the simultaneous BESS antiproton measurements to probe the effect of charge-sign dependent drift on the entering cosmic rays.
Summary
The BESS measurements are presented and compared to simple models of Solar modulation.
Author
Kenichi Sakai
(NASA/GSFC/CRESST/UMBC)
Co-authors
Akira Itazaki
(Kobe University)
Akira Kusumoto
(Kobe University)
Akira Yamamoto
(High Energy Accelerator Research Organization (JP))
Atsushi Horikoshi
(KEK)
Eun Suk Seo
(University of Maryland (US))
Hideyuki Fuke
(ISAS/JAXA)
John Mitchell
Jonathan Ormes
(University of Denver)
Jun NIshimura
Junichi Suzuki
(KEK)
Kazuma Takeuchi
(Kobe University)
Ken-ichi Tanaka
(KEK)
Kenji Matsumoto
(KEK)
Ki-Chun Kim
(University of Maryland)
Ko Abe
(University of Tokyo)
Koji Yoshimura
(Okayama University)
MASAYA HASEGAWA
(KEK)
Makoto Sasaki
(NASA-Natl. Aeronaut. & Space Admin. (US))
Mitsuaki Nozaki
(Kobe University (JP))
Moohyung Lee
(University of Mayland)
Neeharika Thakur
(NASA)
Nicolas Picot-Clemente
(University of Maryland (US))
Reiko Orito
(Tokushima University)
Robert Streitmatter
(NASA)
Ryoko Shinoda
(The University of Tokyo)
Sadakazu Haino
(Academia Sinica (TW))
Shinya Matsuda
(KEK)
Takamasa Yamagami
(ISAS/JAXA)
Teruyuki Kumazawa
(KEK)
Tetsuya Yoshida
(ISAS/JAXA)
Thomas Hams
Yasuhiro Makida
(High Energy Accelerator Research Organization (JP))
Yoshiaki Shikaze
(Kobe University)
Yoshiyuki Takasugi
(Kobe University)
Yosuke Matsukawa
(Kobe University)
Zachary Myers
(University of Maryland)
