TRT Charged SMP

Introduction

The Transition Radiation Tracker (TRT) can be used to measure ionization in excess of a minimum ionizing particle as well as provide a timing measurement for slow particles. This information can provide important discriminators to find Charged stable massive particles (SMP) which appear in many different models.

Discriminators

Currently, several discriminators have been formed to identify either excess ionization or late timing:

• Corrected low-level bits over threshold
• 1/Beta with uncertainty as measured by the trailing bits
• High threshold(HT) hits on track
• Fraction of hits where the bit-pattern is high in the last bit

All of these discriminators except for HT hits require access to the raw bit pattern for all straw hits. Therefore, a new package is being developed to make these discriminators at reconstruction and store them an AOD Container for selected tracks.

Cosmic Studies

We have completed some studies to show that TRT Charged SMP discriminators behave similarly in Monte Carlo and cosmic muons.

Ongoing work from contributing groups

This is a place to put preliminary plots, works in progress, etc.

Indiana University/ University of British Columbia

We are extending the extisting ionization and timing discriminators into the endcap region and accounting for the eta dependence due to track length.

We are putting the discriminators into the reconstruction code so candidate tracks can be stored in the AOD. (The bit pattern will not be available at AOD level.)

Duke University

Moscow MEPHI

Stockholm

CERN/Others

Related Work

https://svnweb.cern.ch/trac/atlasoff/browser/InnerDetector/InDetRecTools/TRT_ElectronPidTools/trunk

Daniel Richter's dE/dx page, DedxWithTheTRT