Tamar AnalysisChapt

Introduction

This chapter will describe the techniques to calculate semi inclusive double spin asymmetries for the following reactions [math]e^-p \rightarrow e^- \pi^+ n[/math] and [math]e^-n \rightarrow e^- \pi^- p[/math] for NH3 and ND3 polarized targets respectively. The goal of this work is the extraction of the ratio of polarized to unpolarized quark distribution functions using double spin asymmetries.
There are couple of main steps in the data analysis, which will be discussed bellow: 1) the data selection, 2) background elimination, 3) the target and beam polarization, 4) the detector acceptance >???????

Radiative Corrections

The radiative correction contribution for the ~5.6 GeV incident electron beam data is less than 5%<ref>http://www.jlab.org/Hall-B/secure/eg1/EG2000/fersch/QUALITY_CHECKS/file_quality/runinfo.txt</ref>. Due to negligible contributions from the radiative corrections they are not included in the double spin asymmetry analysis. There are two types of radiative corrections, internal and external.

Internal radiative corrections describe the contributions which took the place during the lepton-hadron interaction. The emitted photon by the incoming electron is reabsorbed by the same scattered electron. The same reaction can occur for the target nucleon.

On the other hand, the external radiative corrections account for the energy loss from the incoming and scattered lepton by emitting the photon. The same process can be observed for the target nucleon.

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