# Pion Mass and Background

The attached pdf is an earlier version of information on this page and is no longer of interest.

This page links to summaries of all the points for TSSA from run 15, and for pp, pAu, pAl collisions
Updated 8/19/2018

Attached Files.
1) This is a list of cells that I am not using for cross section and AN analysis. This veto occurs very late in my analysis. I remove pions that point to these cells.
2) This is a mathematica simulation of comparison between AN extracted from fits to phi vs Cos(phi).

Many of these points should be removed from a final analysis because of poor statistics but are currently included.

In plots: Black=pp; Red=pAu; Blue=pAl

Column 1: name of point
Column 2: Pt of point.
Column 3: Energy of point
Column 4: Asymmetry with Statistical error and Systematic error from (non-beam background, background under mass peak). Mass range is (.015 to .255 GeV). Fit shown to Cos(phi) distribution.
Column 5:   Low mass Asymmetry with Statistical error and Systematic error from (non-beam background, background under mass peak). Mass range is (.06  to .16 GeV). Fit shown to Cos(phi) distribution.
Column 6: Fraction of non-beam background (with abort gap plots).
Column 7: Polarization used to calculate AN.
Column 8: Fit (same as Column 4) but to phi distribution.
Column 9: Signal Fraction from fit for mass region (.06<M<.16)
Column 10: Signal Fraction from fit for mass region (.015 <M < .255)
Column 11  High mass Asymmetry with Statistical error and Systematic error from (non-beam background, background under mass peak). Mass range is (.16  to .26 GeV). Fit shown to Cos(phi) distribution..
Column 12  High mass  (background) Asymmetry with Statistical error and Systematic error from (non-beam background). Mass range is (.3  to .4 GeV). Fit shown to Cos(phi) distribution..

Raw asymmetry is corrected with the following:

AN=(Raw AN)/pol*(dilution factors from non-beam and mass backgrounds)
dilution factors assume the asymmetry of backgrounds is 50% of the pion asymmetry.
Systematic Uncertainties assume this background asymmetries could vary from 0 to 100% of the pion Asymmetry.

Plot Sets:
Plot errors are statistical only.