Abstract
We present a study of the expected precision of the top quark mass determination, measured at a linear e+ e- collider based on CLIC technology. GEANT4-based detector simulation and full event reconstruction including realistic physics and beam-induced background levels are used. Two different techniques to measure the top mass are studied: The direct reconstruction of the invariant mass of the top quark decay products and the measurement of the mass together with the strong coupling constant in a threshold scan, in both cases including first studies of expected systematic uncertainties. For the direct reconstruction, experimental uncertainties around 100 MeV are achieved, which are at present not matched by a theoretical understanding on a similar level. With a threshold scan, total uncertainties of around 100 MeV are achieved, including theoretical uncertainties in a well-defined top mass scheme. For the threshold scan, the precision at ILC is also studied to provide a comparison of the two linear collider technologies.
Highlights
As the heaviest Standard Model particle, the top quark is of particular interest since it couples most strongly to the Higgs field and may provide sensitivity to Beyond the Standard Model physics
We present a study of the expected precision of the top quark mass determination, measured at a linear e+e− collider based on CLIC technology
A linear e+e− collider based on CLIC technology provides the capabilities for a precise measurement of the mass of the top quark both at and above threshold
Summary
As the heaviest Standard Model particle, the top quark is of particular interest since it couples most strongly to the Higgs field and may provide sensitivity to Beyond the Standard Model physics. Experiments at a future e+e− collider at the high energy frontier offer the possibility for a wide variety of studies involving top quarks, ranging from the precise measurement of the top quark mass and width to the investigation of asymmetries, providing large sensitivity to various New Physics models [5] At such a collider, the mass of the top quark can be determined with two different techniques: through the direct reconstruction of top quarks from their decay products at energies above the production threshold, and through a scan of the top-pair production threshold. The observables used in [6, 7] do not match the invariant mass definition used for the top mass determination above threshold, which was chosen to allow the use kinematic constraints to improve the overall event reconstruction and to provide the possibility of beam-related background suppression via particle-level cuts and jet finding This introduces additional, potentially sizeable, uncertainties in the theoretical interpretation of the measured value. The latter includes a study of the impact of the CLIC luminosity spectrum on the threshold scan compared to that of the ILC, which has a somewhat more peaked spectrum, performed by repeating this analysis using the ILC spectrum
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
