Study of Interaction Between Antiprotons

ZHANG Zhengqiao; MA Yugan

doi:10.11804/NuclPhysRev.34.03.296

With undergoing researches on antimatter physics, it is crucial to understand what the interaction between antiprotons is. Is it the same as the interaction between protons? This measurement will definitely help us to understand the formation mechanism of antimatter nuclei as well as the symmetry of matter and antimatter. In this context, our STAR collaboration measured the correlation function of antiproton-antiproton pairs from 200 GeV/c Au+Au collisions. After substracting the residual correlation due to the secondary antiprotons that decayed from other particles, the primary antiproton-antiproton correlation function is extracted. By applying the quantum theory of multi-particle correlation, two key parameters that characterize the corresponding strong interaction:namely, the scattering length (f₀) and effective range (d₀) were obtained. Within error bars, it is found that the f₀ and d₀ for the antiproton-antiproton interaction are consistent with their antiparticle counterparts -the ones for the proton-proton interaction. Like the force that holds ordinary protons together within the nuclei of atoms, the force between antiprotons is attractive and strong, which overcomes the tendency of the like (negatively) charged particles to repel one another, and allows the antiprotons to bind to form antinucleus. The current measurement is for the first time to measure the interaction between antimatter, it offers a foundation to understanding the structure of more-complex antinuclei and their properties. Also our measurement offers a new way to test the CPT symmetry, which has an important impact for human beings to understand the law of motion in our world.

Study of Interaction Between Antiprotons

1. Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China;

2. University of Chinese Academy of Sciences, Beijing 100049, China

Funds: National Natural Science Foundation of China(11035009, 11220101005, 11421505); National Basic Research Program of China(973 Program)(2014CB845400)

Corresponding author: 10.11804/NuclPhysRev.34.03.296

Received Date: 2016-12-25

Rev Recd Date: 2017-05-10

Publish Date: 2017-07-18

Key words:

Abstract: With undergoing researches on antimatter physics, it is crucial to understand what the interaction between antiprotons is. Is it the same as the interaction between protons? This measurement will definitely help us to understand the formation mechanism of antimatter nuclei as well as the symmetry of matter and antimatter. In this context, our STAR collaboration measured the correlation function of antiproton-antiproton pairs from 200 GeV/c Au+Au collisions. After substracting the residual correlation due to the secondary antiprotons that decayed from other particles, the primary antiproton-antiproton correlation function is extracted. By applying the quantum theory of multi-particle correlation, two key parameters that characterize the corresponding strong interaction:namely, the scattering length (f₀) and effective range (d₀) were obtained. Within error bars, it is found that the f₀ and d₀ for the antiproton-antiproton interaction are consistent with their antiparticle counterparts -the ones for the proton-proton interaction. Like the force that holds ordinary protons together within the nuclei of atoms, the force between antiprotons is attractive and strong, which overcomes the tendency of the like (negatively) charged particles to repel one another, and allows the antiprotons to bind to form antinucleus. The current measurement is for the first time to measure the interaction between antimatter, it offers a foundation to understanding the structure of more-complex antinuclei and their properties. Also our measurement offers a new way to test the CPT symmetry, which has an important impact for human beings to understand the law of motion in our world.

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Reference (36)

[1]	BAUR G, BOERO G, BRAUKSIEPE A, et al. Phys Lett B, 1996, 368(3):251.
[2]	BLANFORD G, CHRISTIAN D C, GOLLWITZER K, et al. Phys Rev Lett, 1998, 80(14):3037.
[3]	AMORETTI M, AMSLER C, BONOMI G, et al. Nature, 2002, 419(6906):456.
[4]	STAR Collaboration. Science, 2010, 328:58.
[5]	STAR Collaboration. Nature, 2011, 473:353.
[6]	MA Yugang. J Phys Conf Ser, 2013, 420:012036.
[7]	MA Yugang, CHEN Jinhui. China Basic Science, 2011, 2:20. (in Chinese) (马余刚, 陈金辉. 中国基础科学, 2011, 2:20.)
[8]	MA Yugang. Science Development Report[R]. Beijing:Chinese Academy of Sciences, 2012:108. (in Chinese) (马余刚. 科学发展报告[R]. 北京:中国科学院, 2012:108.)
[9]	MA Yugang, CHEN Jinhui, XUE Liang. Front Phys, 2012, 7:637.
[10]	AMS Collaboration. Phys Rev Lett, 2013, 110(14):141102.
[11]	AMS Collaboration. Phys Rev Lett, 2014, 113(22):121101
[12]	ALICE Collaboration. Nature Physics, 2015, 11:811.
[13]	STAR Collaboration. Nature, 2015, 527:345.
[14]	XU Zizong. Nuclear and Particle Physics Introduction[M]. Heifei:Press of University of Science and Technology of China, 2009:280. (in Chinese) (许咨宗. 核与粒子物理导论[M]. 合肥:中国科学技术大学出版社, 2009:280.)
[15]	ADAMS J, AGGARWAL M M, AHAMMED Z, et al. Nucl Phys A, 2005, 757:102.
[16]	PHENIX collaboration. Nucl Phys A, 2005, 757:184.
[17]	MA Yugang. Modern Physics, 2013, 25(5):27. (in Chinese) (马余刚. 现代物理知识, 2013, 25(5):27.)
[18]	STAR Collaboration. Nucl Instr Meth A, 2003, 499:624.
[19]	LLOPE W J (for the STAR Collaboration). Nucl Instr Meth A, 2012, 661:s110.
[20]	BROWN R H, TWISS R Q. Nature, 1956, 177(4497):27.
[21]	POCHODZALLA J, GELBKE C K, LYNCH W G, et al. Phys Rev C, 1987, 35:1695.
[22]	GYULASSY M. Phys Rev C, 1979, 20:2267.
[23]	BOAL D H, GELBKE C K, JENNINGS B K. Rev Mod Phys, 1990, 62(3):553.
[24]	LEDNICKY R. Phys Atomic Nuclei, 2004, 67:72.
[25]	LYNCH W G, CHITWOOD C B, TSANG M B, et al. Phys Rev Lett, 1983, 51:1850.
[26]	MA Yugang, WEI Yibin, SHEN Wenqing, et al. Phys Rev C, 2006, 73:014604.
[27]	MA Yugang, CAI Xiangzhou, CHEN Jingen, et al. Nucl Phys A, 2007, 790:299c.
[28]	LISA M A, PRATT S, SOLTZ R, et al. Ann Rev Nucl Part Sci, 2005, 55:357.
[29]	MA Yugang, FAND Deqing, SUN Xiaoyan, et al. Phys Lett B, 2015, 743:306.
[30]	FAND Deqing, MA Yugang, SUN Xiaoyan, et al. Phys Rev C, 2016, 94(4):044621.
[31]	LEDNICKY R, LYUBOSHITZ V L. Sov J Nucl Phys, 1982, 35:770.
[32]	STAR Collaboration. Phys Rev C, 2006, 74:064906.
[33]	STAR Collaboration. Phys Rev Lett, 2015, 114:022301.
[34]	CHOJNACKI M, KISIEL A, FLORKOWSKI W, et al. Comput Phys Commun, 2012, 183:746.
[35]	MATHELITSCH L, VERWEST B J. Phys Rev C, 1984, 29:739.
[36]	ŠLAUS I, AKAISHI Y, TANAKA H. Phys Rep, 1989, 173:257.

Study of Interaction Between Antiprotons

doi: 10.11804/NuclPhysRev.34.03.296

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