Estimation of Combinatoric Background in SeaQuest using an Event-Mixing Method

TL;DR

This paper presents a novel event-mixing method tailored for SeaQuest to accurately estimate and subtract combinatoric background in dilepton pair experiments, eliminating the need for normalization factors.

Contribution

It introduces a specific event-mixing technique that leverages SeaQuest's unique features to directly compute background without additional normalization steps.

Findings

Method accurately estimates combinatoric background.

Demonstrates reliability through extensive tests.

Eliminates need for normalization factor.

Abstract

All experiments observing dilepton pairs (e.g. $e^+e^-$, $\mu^+\mu^-$) must confront the existence of a combinatoric background caused by the combining of tracks not arising from the same physics vertex. Some method must be devised to calculate and remove this background. In this document we describe a particular event-mixing method relying on many of the unique aspects of the SeaQuest spectrometer and data. The method described here calculates the combinatoric background with correct normalization; i.e., there is no need to assign a floating normalization factor that is then determined in a subsequent fitting procedure. Numerous tests are applied to demonstrate the reliability of the method.