A New Limit on the Flux of Cosmic Antihelium

T. Saeki; K. Anraku; S. Orito; J. Ormes; M. Imori; B. Kimbell; Y. Makida; H. Matsumoto; H. Matsunaga; J. Mitchell; M. Motoki; J. Nishimura; M. Nozaki; M. Otoba; T. Sanuki; R. Streitmatter; J. Suzuki; K. Tanaka; I. Ueda; N. Yajima; T. Yamagami; A. Yamamoto; T. Yoshida; K. Yoshimura

doi:10.1016/s0370-2693(98)00131-2

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arXiv · astro-ph/9710228

A New Limit on the Flux of Cosmic Antihelium

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Abstract

A very sensitive search for cosmic-ray antihelium was performed using data obtained from three scientific flights of BESS magnetic rigidity spectrometer. We have not observed any antihelium; this places a model-independent upper limit (95 % C.L.) on the antihelium flux of 6*10**(-4) m**(-2)sr**(-1)s**(-1) at the top of the atmosphere in the rigidity region 1 to 16 GV, after correcting for the estimated interaction loss of antihelium in the air and in the instrument. The corresponding upper limit on the Hebar/He flux ratio is 3.1*10**(-6), 30 times more stringent than the limits obtained in similar rigidity regions with magnetic spectrometers previous to BESS.

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T. Saeki, K. Anraku, S. Orito, J. Ormes, M. Imori, B. Kimbell, Y. Makida, H. Matsumoto, H. Matsunaga, J. Mitchell, M. Motoki, J. Nishimura, M. Nozaki, M. Otoba, T. Sanuki, R. Streitmatter, J. Suzuki, K. Tanaka, I. Ueda, N. Yajima, T. Yamagami, A. Yamamoto, T. Yoshida, K. Yoshimura. 1997-10-21. A New Limit on the Flux of Cosmic Antihelium. https://doi.org/10.1016/s0370-2693(98)00131-2

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