Abstract
A search for C P violation in D+ -> phi pi(+) decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb(-1) at a centre of mass energy of 7 TeV. The CP-violating asymmetry is measured to be (-0.04 +/- 0.14 +/- 0.14)% for candidates with K-K+ mass within 20 MeV/c(2) of the phi meson mass. A search for a CP-violating asymmetry that varies across the phi mass region of the D+ -> K-K+pi(+) Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D-s(+) -> K-S(0)pi(+) decay is measured to be (0.61 +/- 0.83 +/- 0.14)%.
Highlights
The asymmetry AK0 ≡ (NK0 − NK0)/(NK0 + NK0) = −AK0, where NK0/K0 is the number of K0/K0 mesons produced, takes into account the detection asymmetry between a K0 and a K0 meson due to regeneration and the presence of mixing and CP violation in the K0-K0 system
Assuming that CP violation in the Cabibbo-favoured decays is negligible, ADCPD is a measurement of the sum of the CP -violating asymmetries in D± → KS0K± and Ds± → KS0π± decays, ADCP±→KS0K± + ADCPs±→KS0π± = ADCPD
The quantity ADCPD provides a measurement that is largely insensitive to production and instrumental asymmetries, even though the CP asymmetries in D± → KS0K± and Ds± → KS0π± decays are expected to have the opposite sign
Summary
The LHCb detector [16] is a single-arm forward spectrometer covering the pseudorapidity range 2 < η < 5, designed for the study of particles containing b or c quarks. The detector includes a high-precision tracking system consisting of a silicon-strip vertex detector surrounding the pp interaction region, a large-area silicon-strip detector located upstream of a dipole magnet with a bending power of about 4 Tm, and three stations of silicon-strip detectors and straw drift tubes placed downstream. The polarity of the dipole magnet is reversed periodically throughout data-taking. The data used in this analysis corresponds to an integrated luminosity of approximately fb−1 recorded in pp collisions at centre-of-mass energies of. Decays of hadronic particles are described by EvtGen [22], in which final state radiation is generated using Photos [23]. The interaction of the generated particles with the detector and its response are implemented using the Geant toolkit [24, 25] as described in ref. The interaction of the generated particles with the detector and its response are implemented using the Geant toolkit [24, 25] as described in ref. [26]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
