Observation of an excited Bc(±) meson state with the ATLAS detector.
Observation of an excited Bc(±) meson state with the ATLAS detector.
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使用 ATLAS 探测器观察激发的 Bc(±) 介子态。
DOI：
10.1103/physrevlett.113.212004
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发表时间：
2014
影响因子：
8.6
通讯作者：
Aad G
中科院分区：
文献类型：
--
作者：
Aad G
用在大型强子对撞机上收集的7TeV的4.9 FB−1和8TeV的19.2 FB−1的碰撞数据，对B[±over c]介子的激发态进行了研究。通过其到基态的强子跃迁观察到一个新的态，后者在衰变B[±over c]→J/ψπ±中被检测到。这种状态出现在m(B[±over c])π+π−)−m(B[±over c])−2m(π±)质量差分布中，显著的标准偏差为5.2。观测到的态质量为6842±4±5 MeV，其中第一个误差是统计误差，第二个误差是系统误差。这种态的质量和衰变与对B[±over c]介子B[±over c](2S)第二S波态的预期是一致的。
A search for excited states of the B[± over c] meson is performed using 4.9 fb−1of 7 TeV and 19.2 fb−1of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay B[± over c] → J/ψπ±. The state appears in the m(B[± over c]π+π−) − m(B[± over c]) − 2m(π±) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842 ± 4 ± 5 MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the B[± over c] meson, B[± over c](2S).