単位電荷のクォーク:異常な水素探査

R A Muller, L W Alvarez, W R Holley

Science (New York, N.Y.)

|April 29, 1977

まとめ

研究者は,高エネルギー質量スペクトロメーターを使用して,1+1電荷のクォークを含む異常な水素を探した. クォークは検出されず,陽子と比較してクォークの豊富さの新しい限界を確立しました.

科学分野:

素粒子物理学素粒子物理学について
核物理学核物理学とは
コスモロジー・コスモロジーとは

背景:

安定クォークの存在は理論上の可能性である.
異常な水素同位体は,標準モデルを超えた新しい物理学の証拠を提供することができる.
以前の安定クォークの探求は,ゼロの結果をもたらし,実験の感度を改善する必要がありました.

研究の目的:

+1. 1の電荷を持つ安定したクォークを探すために.
異常な水素同位体の存在を調査するために.
そのような粒子の豊富さの実験的限界を確立するために.

主な方法:

高エネルギー質量スペクトロメータとして,バークレーの88インチサイクロトロンを使用した.
イオン源として天然水素とデュテリウムを使用した.
離子束を分析し,質量と電荷に基づいて異常な粒子の存在を確認した.

主要な成果:

+1電荷のクォークやその他の異常な水素同位体についての証拠は観察されなかった.
クォークと陽子の比に実験的な限界が設定されました.
限界値は,高質量 (3−8.2原子質量単位) に対して2×10−19未満から,低質量 (<1/3原子質量単位) に対して10−13までである.

結論:

この研究は,安定クォークの豊富さに厳格な新しい限界を設けている.
異常な水素の観測がないことは,そのような粒子が希少または存在しないことを示唆しています.
高い感度を持つさらなる実験は,より低い豊富な限界を調査するために必要になるかもしれません.

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