Measurement of the cosmic ray antiproton/proton flux ratio at TeV energies with the ARGO-YBJ detector

6533b85dfe1ef96bd12bdf57

RESEARCH PRODUCT

Measurement of the cosmic ray antiproton/proton flux ratio at TeV energies with the ARGO-YBJ detector

X. X. Li I. De Mitri M. Iacovacci M. Zha G. D'alí Staiti Zhenyong Feng P. Vallania S. Vernetto C. Cattaneo F. R. Zhu C. Liu T. L. Chen X. H. Ma H.h. He S. W. Cui Jilong Zhang F. Ruggieri Q. Q. Zhu P. Bernardini S. Catalanotti M. Panareo Giovanni Mancarella T. Di Girolamo B. D'ettorre Piazzoli Y. Q. Guo Carla Bleve C. Y. Wu E. Giroletti B. Panico P. Salvini Zhaxiciren R. Santonico Zihuang Cao Y. B. Chen H. J. Li Paolo Camarri C. Q. Liu H. R. Wu Hongbo Hu L. Xue C. F. Feng A. K. Calabrese Melcarne A. F. Yuan Carlo Vigorito B. Z. Dai Paolo Montini R. Iuppa B. Bartoli Hong-peng Lu X. Y. Zhang X. C. Yang G. Marsella Haibing Hu Cristian Stanescu P. Branchini Y. X. Yan Antonio Budano B. S. Wang J. K. K. Liu Zhaxisangzhu Labaciren Irina James Y. Zhang Chang-chun Ning Zhaoyang Feng D. Martello Longzhou Zhang L. Perrone Jianli Zhang P. Creti P. Pistilli H. M. Zhang X. X. Zhou Z. G. Yao Bingwei Xu A. Surdo Q. Huang Huaguang Wang G. Liguori Fudong Shi S. Mastroianni Q. B. Gou X. D. Sheng P. R. Shen P. F. Zhang X. J. Bi S. Z. Chen S. M. Mari X. B. Qu X. H. Ding Roberto Cardarelli G. Di Sciascio Y. H. Tan J. Y. Li M. Y. Liu Q. Y. Yang H. Y. Jia Danzengluobu G. Zizzi I. Bolognino A. Pagliaro

subject

Physics Nuclear and High Energy Physics Antiparticle Astrophysics::High Energy Astrophysical Phenomena Dark matter Settore FIS/01 - Fisica Sperimentale Earth-Moon Cosmic ray magnetic spectrometer Cosmic ray High Energy Physics - Experiment Nuclear physics Earth's magnetic field Antiproton Antimatter antiproton Content (measure theory)Antiproton-Proton ratio Cosmic rays Extended Air Showers Astrophysics - High Energy Astrophysical Phenomena Energy (signal processing)

description

Cosmic ray antiprotons provide an important probe to study the cosmic ray propagation in the interstellar space and to investigate the existence of dark matter. Acting the Earth-Moon system as a magnetic spectrometer, paths of primary antiprotons are deflected in the opposite sense with respect to those of the protons in their way to the Earth. This effect allows, in principle, the search for antiparticles in the direction opposite to the observed deficit of cosmic rays due to the Moon (the so-called `Moon shadow'). The ARGO-YBJ experiment, located at the Yangbajing Cosmic Ray Laboratory (Tibet, P.R. China, 4300 m a.s.l., 606 g/cm$^2$), is particularly effective in measuring the cosmic ray antimatter content via the observation of the cosmic rays shadowing effect due to: (1) good angular resolution, pointing accuracy and long-term stability; (2) low energy threshold; (3) real sensitivity to the geomagnetic field. Based on all the data recorded during the period from July 2006 through November 2009 and on a full Monte Carlo simulation, we searched for the existence of the shadow cast by antiprotons in the TeV energy region. No evidence of the existence of antiprotons is found in this energy region. Upper limits to the $\bar{p}/p$ flux ratio are set to 5 % at a median energy of 1.4 TeV and 6 % at 5 TeV with a confidence level of 90%. In the TeV energy range these limits are the lowest available.

year	journal	country	edition	language
2012-01-18

10.1103/physrevd.85.022002 http://arxiv.org/abs/1201.3848