CERN Accelerating science

LHCb Note
Report number	LHCb-CONF-2012-009 ; CERN-LHCb-CONF-2012-009
Title	First observations and branching fraction measurements of $\bar{B}_s^0$ to double-charm final states
Corporate author(s)	The LHCb Collaboration
Collaboration	LHCb Collaboration
Note	Linked to LHCb-ANA-2012-001 Not published in the proceedings
Submitted to	47th Rencontres de Moriond on QCD and High Energy Interactions, La Thuile, Italy, 10 - 17 Mar 2012
Submitted by	lalaine.barbon.strebel@cern.ch on 28 Feb 2012
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; LHCb
Free keywords	flavour physics ; B physics ; spectroscopy ; branching fraction ; CP violation ; CKM angle gamma
Abstract	First observations and measurements of the branching fractions of the $\bar{B}_s^0$ decay modes $\bar{B}_s^0\to D^+D^-$, $\bar{B}_s^0\to D_s^+D^-$, and $\bar{B}_s^0\to D^0\bar{D}^0$ are made using 1 fb$^{-1}$ of data collected by the LHCb detector. These branching fractions are normalized to $\bar{B}^0\to D^+D^-$, $B^0\to D_s^+D^-$ and $B^-\to D^0D_s^-$, respectively, from which we obtain ${\cal{B}}(\bar{B}_s^0\to D^+D^-)/{\cal{B}}(\bar{B}^0\to D^+D^-) = 1.00\pm 0.18\pm 0.09$, ${\cal{B}}(\bar{B}_s^0 \to D_s^+D^-)/{\cal{B}}(B^0\to D_s^+D^-)=0.048\pm0.008\pm0.004$, and ${\cal{B}}(\bar{B}_s^0\to D^0\bar{D}^0)/{\cal{B}}(B^-\to D^0D_s^-)=0.015\pm0.004\pm0.002$. The branching ratio of the decay $\bar{B}_s^0\to D_s^+D_s^-$ relative to $\bar{B}^0\to D^+D_s^-$ has also been measured and is found to be ${\cal{B}}(\bar{B}_s^0\to D_s^+D_s^-)/{\cal{B}}(\bar{B}^0\to D^+D_s^-)= 0.508\pm 0.026\pm 0.043$. This measurement is about five times more precise than the current world average.
Copyright/License	Preprint: (License: CC-BY-4.0)

Corresponding record in: Inspire
Email contact(s) : s.blusk@syr.edu ; michael.williams@imperial.ac.uk