Particle identification at FCC-ee
European Physical Journal Plus 136:8 (2021)
Abstract:
Equipping an experiment at FCC-ee with particle identification (PID) capabilities, in particular the ability to distinguish between hadron species, would bring great benefits to the physics programme. Good PID is essential for precise studies in quark flavour physics and is also a great asset for many measurements in tau, top, and Higgs physics. The requirements placed by flavour physics and these other applications are surveyed, with an emphasis on the momentum range over which PID is necessary. Possible solutions are discussed, including classical RICH counters, time-of-flight systems, and dE/dx and cluster counting. Attention is paid to the impact on the global detector design that including PID capabilities would imply.Heavy-quark opportunities and challenges at FCC-ee
The European Physical Journal Plus Springer Nature 136:8 (2021) 837
Determination of quantum numbers for several excited charmed mesons observed in B − → D * + π − π − decays
Physical Review D American Physical Society 101:3 (2020) 32005
Abstract:
A four-body amplitude analysis of the B− → D*+π−π− decay is performed, where fractions and relative phases of the various resonances contributing to the decay are measured. Several quasi-model-independent analyses are performed aimed at searching for the presence of new states and establishing the quantum numbers of previously observed charmed meson resonances. In particular the resonance parameters and quantum numbers are determined for the D1(2420), D1(2430), D0(2550), D∗1(2600), D2(2740) and D∗3(2750) states. The mixing between the D1(2420) and D1(2430) resonances is studied and the mixing parameters are measured. The dataset corresponds to an integrated luminosity of 4.7fb−1, collected in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV with the LHCb detector.Observation of the decays chi(cJ) -> phi phi eta
Physical Review D American Physical Society 101:1 (2020) 12012
Abstract:
Using a data sample of (448.1±2.9)×106 ψ(3686) decays collected by the BESIII detector at the Beijing Electron Positron Collider (BEPCII), we observe the decays χcJ→φφη(J=0,1,2), where the χcJ are produced via the radiative processes ψ(3686)→γχcJ. The branching fractions are measured to be B(χc0→φφη)=(8.41±0.74±0.62)×10-4, B(χc1→φφη)=(2.96±0.43±0.22)×10-4, and B(χc2→φφη)=(5.33±0.52±0.39)×10-4, where the first uncertainties are statistical, and the second are systematic. We also search for intermediate states in the φφ or ηφ subsystems, but no significant structure is seen due to the limited statistics.Improved sensitivity to the CKM phase γ through binning phase space in B− → DK−, D → K+π−π−π+ decays
Physics Letters B Elsevier 802:10 March 2020 (2020) 135188