於緊湊渺子線圈質心能量十三兆電子伏特中測量 LambdaB->Jpsi pK 與 LambdaB->Jpsi Lambda0 分支分數比

Abstract

本研究利用大強子對撞機上的緊湊緲子線圈偵測器測量LambdaB->Jpsi pK 衰變通道對 LambdaB->Jpsi Lambda0 衰變通道的分支分數比。 此次實驗分析中心能量為十三兆電子伏特與 35.798 逆飛靶恩等效累積光度數據量的質子與質子對撞結果回報 測量到的分支分數比為： Br(LambdaB->Jpsi pK+) ------------------------------------------- = 0.964+-0.123(stat.)+-0.071(syst.) Br(LambdaB->Jpsi Lambda0) Br(LambdaBbar->Jpsi pbar K+) ------------------------------------------- = 1.037+-0.139(stat.)+-0.078(syst.) Br(LambdaBbar->Jpsi Lambda0bar) 此外，我們也回報兩個衰變通道中電荷-宇稱對稱的直接測量結果： LambdaB->Jpsi pK = 0.011+-0.064+0.004-0.010 LambdaB->Jpsi Lambda0 = 0.057 +- 0.037 +0.005-0.002 而數據顯示沒有發現電荷-宇稱對稱破壞。

This research measures the branching fraction ratio of LambdaB->Jpsi pK to LambdaB->Jpsi Lambda0 in proton-proton collisions at a centre-of-mass energy sqrt s = 13 TeV, using 35.798 inverse femtobarn integrated luminosity of data recorded with the CMS detector at the Large Hadron Collider. The branching fraction ratios are measured to be Br(LambdaB->Jpsi pK+) ------------------------------------------- = 0.964+-0.123(stat.)+-0.071(syst.) Br(LambdaB->Jpsi Lambda0) Br(LambdaBbar->Jpsi pbar K+) ------------------------------------------- = 1.037+-0.139(stat.)+-0.078(syst.) Br(LambdaBbar->Jpsi Lambda0bar) We also report the direct charge-parity asymmetry A_CP measurement for both channels as LambdaB->Jpsi pK = 0.011+-0.064+0.004-0.010 LambdaB->Jpsi Lambda0 = 0.057 +- 0.037 +0.005-0.002 , which shows that no charge asymmetry is observed in these decay.