Precision measurement of the ratio of the ? b 0 to B ¯ 0 lifetimes
Precision measurement of the ratio of the ? b 0 to B ¯ 0 lifetimes
复制标题
精确测量 ? 的比率
DOI：
10.1016/j.physletb.2014.05.021
复制
发表时间：
2014
影响因子：
4.4
通讯作者：
Aaij R
中科院分区：
文献类型：
--
作者：
Aaij R
LHCb测量的Λb0重子与B-0介子的寿命比，使用对应于在LHC上使用7和8 TeV质心能量pp碰撞收集的3.0 fb-1的综合光度的数据进行了更新。所用的衰变模式为Λb0→J/ψ pk和B-0→J/ψπ+ K-，其中π+ K-质量与K-* 0（892）介子的质量一致。寿命比以前所未有的精度测定为0.974±0.006±0.004，其中第一不确定性为统计不确定性，第二不确定性为系统不确定性。这一结果与最初基于重夸克膨胀的理论预测是一致的。利用目前世界平均的B-0寿命，Λb0寿命为1.479±0.009±0.010 ps。
The LHCb measurement of the lifetime ratio of the Λb0 baryon to the B-0 meson is updated using data corresponding to an integrated luminosity of 3.0 fb-1 collected using 7 and 8 TeV centre-of-mass energy pp collisions at the LHC. The decay modes used are Λb0→ J/ψpK-and B-0→ J/ψπ+ K-, where the π+ K-mass is consistent with that of the K-* 0 (892) meson. The lifetime ratio is determined with unprecedented precision to be 0.974±0.006±0.004, where the first uncertainty is statistical and the second systematic. This result is in agreement with original theoretical predictions based on the heavy quark expansion. Using the current world average of the B-0 lifetime, the Λb0 lifetime is found to be 1.479±0.009±0.010 ps.