Experimental study of opposite-sign and same-sign dimuon events produced in wide-band neutrino and antineutrino beams
Experimental study of opposite-sign and same-sign dimuon events produced in wide-band neutrino and antineutrino beams
复制标题
宽带中微子和反中微子束中产生的异号和同号双子事件的实验研究
DOI：
10.1016/0370-2693(81)90821-2
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发表时间：
1981
影响因子：
4.4
通讯作者：
V. Valente
中科院分区：
文献类型：
--
作者：
M. Jonker;J. Panman;F. Udo;J. Allaby;U. Amaldi;G. Barbiellini;W. Flegel;W. Kozanecki;K. Mess;M. Metcalf;J. Meyer;P. Monacelli;R. Orr;A. Wetherell;K. Winter;V. Blobel;F. Büsser;P. Gall;H. Grote;B. Kröger;E. Metz;F. Niebergall;K. Ranitzsch;P. Stähelin;P. Gorbunov;E. Grigoriev;V. Kaftanov;V. Khovansky;A. Rosanov;A. Baroncelli;R. Biancastelli;B. Borgia;C. Bosio;A. Capone;F. Ferroni;E. Longo;F. Notaristefani;P. Pistilli;C. Santoni;V. Valente
本文报道了用CHARM中微子探测器在CERN超级质子同步加速器（SPS）喇叭聚焦束流中获得的495 ± 32 νμ和285 ± 29 νμ诱导的瞬发反号双μ子事件。使用观察到的顶点处两个μ子之间的距离分布来选择提示事件。观察到的增加提示双μ子单μ子事件与Evisis兼容的魅力夸克的生产和衰变的预期行为的比例。在GIM机制下，我们发现奇异海的贡献为0.050 ± 0.015，这与我们以前的结果一致。在同一样品中，我们观察到74 ± 17 νμ和52 ± 13 νμ诱导的瞬发同号双μ子事件。根据它们的运动学，这些事件可以很好地描述为强子起源。μ−μ−/μ−μ+和μ+μ+/μ+μ−的比值为0.14 ± 0.04（stat.）± 0.03（系统）0.18 ± 0.06（stat.）± 0.03（系统），分别观测到的比值σ（μ+μ+）σ（μ−μ−）= 0.50 ± 0.20与单μ子带电截面的比值σ（νμ N → μ+X）σ（ν μ N → μ−X）= 0.498 ± 0.019是一致的。
We report on a study of 495 ± 32 νμ-induced and 285 ± 29 νμ- induced prompt opposite-sign dimuon events, obtained in the CERN Super Proton Synchrotron (SPS) horn-focused beam, using the CHARM neutrino detector. Prompt events are selected using the observed distribution of the distance between the two muons at the vertex. The observed increase of the ratio of prompt dimuon to single muon events with Evisis compatible with the expected behaviour for charm quark production and decay. Assuming the GIM mechanism, we fond a strange-sea contribution of 0.050 ± 0.015, in agreement with our previous result not involving the charm-changing currents. In the same sample we observed 74 ± 17 νμ-induced and 52 ± 13 νμ- induced prompt same-sign dimuon events. On the basis of their kinematics, these events can be well described as being of hadronic origin. The ratios μ−μ−/μ−μ+and μ+μ+/μ+μ−are found to be 0.14 ± 0.04 (stat.) ± 0.03 (syst.) and 0.18 ± 0.06 (stat.) ± 0.03 (syst.), respectively. The observed ratio σ(μ+μ+) σ(μ−μ−) = 0.50 ± 0.20 is compatible with the ratio of the single-muon charged-current cross sections, σ( νμN → μ+X ) σ(νμN → μ−X ) = 0.498 ± 0.019 .