Publisher Correction: The asymmetry of antimatter in the proton
Publisher Correction: The asymmetry of antimatter in the proton
复制标题
出版商更正：质子中反物质的不对称性
DOI：
10.1038/s41586-022-04707-z
复制
发表时间：
2022
期刊：
影响因子：
64.8
通讯作者：
Tadepalli, A. S.
中科院分区：
文献类型：
--
作者：
Dove, J.;Kerns, B.;McClellan, R. E.;Miyasaka, S.;Morton, D. H.;Nagai, K.;Prasad, S.;Sanftl, F.;Scott, M. B.;Tadepalli, A. S.
质子的基本构件--夸克和胶子--几十年来一直为人所知。然而，对于这些粒子及其动力学如何引起质子的量子束缚态及其物理性质，如其自旋，我们在理论和实验上仍有不完全的理解。在最简单的图片中，构成质子的两个上夸克和一个下夸克只占质子质量的几分之一，其中大部分以夸克动能和势能以及来自强力的胶子能量的形式存在。正如量子色动力学所描述的那样，这种力的一个基本特征是它能够在质子内创造出只存在很短时间的物质-反物质夸克对。它们的短暂存在使得研究质子中的反物质夸克变得困难，但在物质-反物质夸克对湮灭的反应中，可以辨别出它们的存在。在这张由强力产生夸克-反夸克的图片中，考虑到上下反物质夸克的质量与质子的质量非常相似且很小，作为动量函数的概率分布应该几乎相同。在这里，我们提供了来自Muon对产生测量的证据，证明这些分布是相当不同的，在大范围的动量范围内，下反物质夸克比上反物质夸克更丰富。这些结果有望重新唤起人们对质子中反物质不对称性起源的几种拟议机制的兴趣，这些机制之前的结果并不受欢迎，并指出未来的测量可以区分这些机制。
The fundamental building blocks of the proton—quarks and gluons—have been known for decades. However, we still have an incomplete theoretical and experimental understanding of how these particles and their dynamics give rise to the quantum bound state of the proton and its physical properties, such as its spin. The two up quarks and the single down quark that comprise the proton in the simplest picture account only for a few per cent of the proton mass, the bulk of which is in the form of quark kinetic and potential energy and gluon energy from the strong force. An essential feature of this force, as described by quantum chromodynamics, is its ability to create matter–antimatter quark pairs inside the proton that exist only for a very short time. Their fleeting existence makes the antimatter quarks within protons difficult to study, but their existence is discernible in reactions in which a matter–antimatter quark pair annihilates. In this picture of quark–antiquark creation by the strong force, the probability distributions as a function of momentum for the presence of up and down antimatter quarks should be nearly identical, given that their masses are very similar and small compared to the mass of the proton. Here we provide evidence from muon pair production measurements that these distributions are considerably different, with more abundant down antimatter quarks than up antimatter quarks over a wide range of momenta. These results are expected to revive interest in several proposed mechanisms for the origin of this antimatter asymmetry in the proton that had been disfavoured by previous results, and point to future measurements that can distinguish between these mechanisms.