A. G. Mayorov, A. M. Gal'per, O. Adriani, G. A. Bazilevskaya, G. Barbarino, R. Bellotti, M. Boezio, E. A. Bogomolov, V. Bonvicini, M. Bongi, L. Bonechi, S. V. Borisov, S. Bottai, A. Bruno, S. Vacci, E. Vannuccini, G. I. Vasiliev, S. A. Voronov, Y. Wu, I. A. Danilchenko, W. Gillard, G. Jerse, G. Zampa, N. Zampa, V. G. Zverev, M. Casolino, D. Campana, R. Carbone, A. V. Karelin, P. Carlson, G. Castellini, А. Cafagna, A. N. Kvashnin, S. V. Koldashov, S. A. Koldobsky, S. Yu. Krutkov, A. A. Leonov, V. V. Malakhov, v. Malvezzi, L. Marcelli, W. Menn, V. V. Mikhailov, E. Mocchiutti, N. Mori, N. V. Nikonov, G. Osteria, S. Pizzolotto, P. Papini, M. P. De Pascale, P. Picozza, M. Pearce, M. Ricci, S. Ricciarini, M. F. Runtso, M. Simon, N. De Simone, R. Sparvoli, P. Spillantini, Yu. I. Stozhkov, V. Di Felice, Yu. T. Yurkin, “Upper limit on the antihelium flux in primary cosmic rays”, Pis'ma v Zh. Èksper. Teoret. Fiz., 2011, Volume 93, Issue 11,Pages <nobr>704

This article is cited in 20 papers

FIELDS, PARTICLES, AND NUCLEI

Upper limit on the antihelium flux in primary cosmic rays

A. G. Mayorov^a, A. M. Gal'per^a, O. Adriani^b, G. A. Bazilevskaya^c, G. Barbarino^b, R. Bellotti^d, M. Boezio, E. A. Bogomolov^ef, V. Bonvicini^f, M. Bongi^b, L. Bonechi^b, S. V. Borisov^ag, S. Bottai^b, A. Bruno^d, S. Vacci^f, E. Vannuccini^b, G. I. Vasiliev^e, S. A. Voronov^a, Y. Wu^h, I. A. Danilchenko^a, W. Gillard^h, G. Jerse^g, G. Zampa^f, N. Zampa^f, V. G. Zverev^a, M. Casolino^g, D. Campanaⁱ, R. Carboneⁱ, A. V. Karelin^a, P. Carlson^h, G. Castellini^j, А. Cafagna^d, A. N. Kvashnin^k, S. V. Koldashov^a, S. A. Koldobsky^a, S. Yu. Krutkov^e, A. A. Leonov^a, V. V. Malakhov^a, v. Malvezzi^g, L. Marcelli^g, W. Menn^l, V. V. Mikhailov^a, E. Mocchiutti^f, N. Mori^b, N. V. Nikonov^gf, G. Osteriaⁱ, S. Pizzolotto^f, P. Papini^b, M. P. De Pascale^g, P. Picozza^g, M. Pearce^j, M. Ricci^m, S. Ricciarini^b, M. F. Runtso^a, M. Simon^l, N. De Simone^g, R. Sparvoli^g, P. Spillantini^b, Yu. I. Stozhkov^k, V. Di Felice^g, Yu. T. Yurkin^a

^a National Engineering Physics Institute "MEPhI", Moscow
^b Dipartimento di Fisica, Università di Firenze
^c P.N.Lebedev Physical Institute, the USSR Academy of Sciences
^d INFN, Structure of Bari and Physics Department of University of Bari
^e Ioffe Physico-Technical Institute, Russian Academy of Sciences
^f University of Trieste
^g INFN, Structure of Rome Tor Vergata" and Physics Department ofUniversity of Rome Tor Vergata
^h KTH, Department of Physics
ⁱ INFN, Structure of Naples and Physics Department of University of Naples Federico II
^j IFAC, Sesto Fiorentino
^k P. N. Lebedev Physical Institute, Russian Academy of Sciences
^l Physics Department of Universitat Siegen
^m INFN — National Institute of Nuclear Physics, Laboratori Nazionali di Frascati

Abstract: The explanation of the observed baryon asymmetry, i.e., the almost complete absence of antimatter in the visible part of the universe, is one of the most important problems in cosmology. The real asymmetry value can be determined by direct measurements of the fluxes of antinuclei with charges $|Z| \geq 2$ in primary cosmic rays near the Earth. The results of the search for antihelium using data from the PAMELA experiment obtained from June 2006 to December 2009 are presented. No events with a charge of $-2$ have been detected in the rigidity range of $0.6$–$600$ GV. An upper limit on the antihelium/helium flux ratio overline $\overline{\mathrm{He}}/\mathrm{He}$ can only appear in a matrix or array has been presented as a function of the energy. An integral upper level of $4.7\cdot10^{-7}$ is the lowest limit at rigidities above $14$ GV.

Received: 25.04.2011