International Workshop on Future Linear Colliders, LCWS2024

Reimagining Linear Collider Luminosity Measurement

9 Jul 2024, 14:40

20m

Conference room (3F) (Ito International Research Center)

Oral presentation (in person) Top quark, QCD, Flavour, Precision Modelling Top, QCD, Flavor, Precision Modelling

Speaker

Graham Wilson

Description

Our recent work has shown that a novel, much higher granularity
forward calorimetry concept can enable much more detailed and precise
reconstruction than the baseline designs based on LEP luminometers, together
with the capability of electron/positron/photon separation.

This new calorimeter concept is designed primarily to maximize the acceptance
for $e^{+}{e}^{-}\to \gamma \gamma$ as an alternative luminosity process, where it serves
to define the inner edge of the acceptance (there is no outer edge - as the
complete detector is used in the measurement), while continuing to provide
the standard luminosity measurement from small angle Bhabhas. It will also
serve as a general forward electromagnetic calorimeter helping ensure hermeticity
and detecting individual electrons, positrons and photons.

In this contribution we will highlight the Bhabha rejection capability in the
context of the $e^{+}{e}^{-}\to \gamma \gamma$ luminosity measurement and investigate the
utility of a Bhabha ``mini-tracker'' consisting of a few planes of
upstream thin silicon detectors. This will further refine the $e^{+}$/$e^{-}$ polar angle
measurement, improve Bhabha rejection (for $\gamma \gamma$), and,
last-but-not-least, help mitigate the beam-induced electromagnetic deflection
that biases the Bhabha acceptance by providing high precision longitudinal
vertex information in Bhabha events than can be used in diagnosing this
beam/final-state $e^{+}$/$e^{-}$ effect.

Presentation materials

LCWS-Lumi.pdf

Peer reviewing

Paper

Accepted on 3 Dec 2024 by Junping Tian

LCWSProc_LumiConcept_Revised-V2.pdf