Event-by-Event Estimate of Muon Energy Loss in ATLAS

Abstract

Abstract-The ATLAS Muon Spectrometer is designed to provide efficient and precise stand-alone momentum measurement for muons of momentum up to O(1 TeV/c). The fluctuations of the muon energy loss in the material upstream of the Muon Spectrometer could deteriorate the physics performance, which requires the momentum to be determined at the interaction point. A method to account for this energy loss using the calorimeter information is presented. The method provides an estimate of the energy loss on an event-by-event basis thus reducing the statistical fluctuations. The improvement in the momentum resolution by the significant suppression of the non-Gaussian tails of the energy loss is demonstrated using simulated single muon data. The performance of the method on physics samples with muons in the final state is also briefly discussed.

Calorimetric Measurement of Multi-TeV Muons via Deep Regression

“…-V [9]: The number of muon trajectory-seeded clusters (type-1 clusters); -V [10]: The maximum number of cells among type-1 clusters; -V [11]: The maximum total energy among type-1 clusters; -V[12]: The maximum extension along x of type-1 clusters; -V [13]: The maximum extension along y of type-1 clusters; -V [14]: The maximum extension along z of type-1 clusters; -V [16]: Average number of cells included in type-1 clusters. -V [17]: The number of clusters seeded by a cell not belonging to the muon trajectory (type-2 clusters); -V [18]: The maximum number of cells among type-2 clusters; -V [19]: The maximum total energy among type-2 clusters; -V [20]: Ratio between maximum energy and maximum number of cells of type-2 clusters; -V [21]: Average number of cells included in type-2 clusters.…”

“…6.3 Fig. 20 2D histograms showing the dependence of features V [20] to V [27] (on the y axes) on true muon energy (on the x axes). Features are defined in Sect.…”

“…V [14] V [15] V [16] V [17] V [18] V [19] V [20] V [21] V [22] V [23] V [24] V [25] V [26] V [27] from which we get…”

“…1 To our knowledge, a measurement strategy has been demonstrated only in the IceCube experiment [18,19], where the energy of muons of interest is still higher than that investigated in this work, and the thickness in radiation lengths of the traversed detector material is over an order of magnitude larger than that of present-day collider detectors. Moreover, attempts to aid the muon reconstruction with the energy sum in the calorimeters have been made by the ATLAS Collaboration [20,21].…”

Study on the discovery of new heavy, neutral gauge bosons with the ATLAS experiment

“…To extend the track back to the Inner Detector the effects of multiple scattering of muons and energy losses in the Calorimeters should be taken into consideration. The Muonboy calculates the energy loss based on the material penetrated by the muons in the calorimeter, while MUID additionally uses the measurements of the calorimeter where they are sufficiently larger than the most probable value and the muon appears to be isolated [48].…”