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Title: Kinematic Fitting of Detached Vertices

Abstract

The eg3 experiment at the Jefferson Lab CLAS detector aims to determine the existence of the $$\Xi_{5}$$ pentaquarks and investigate the excited $$\Xi$$ states. Specifically, the exotic $$\Xi_{5}^{--}$$ pentaquark will be sought by first reconstructing the $$\Xi^{-}$$ particle through its weak decays, $$\Xi^{-}\to\pi^{-}\Lambda$$ and $$\Lambda\to\pi^{-}$$. A kinematic fitting routine was developed to reconstruct the detached vertices of these decays, where confidence level cuts on the fits are used to remove background events. Prior to fitting these decays, the exclusive reaction $$\gamma D\rightarrow pp\pi^{-}$$ was studied in order to correct the track measurements and covariance matrices of the charged particles. The $$\Lambda\rightarrow p\pi^{-}$$ and $$\Xi^{-}\to\pi^{-}\Lambda$$ decays were then investigated to demonstrate that the kinematic fitting routine reconstructs the decaying particles and their detached vertices correctly.

Authors:
 [1]
  1. Rice Univ., Houston, TX (United States)
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility, Newport News, VA
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
903056
Report Number(s):
JLAB-PHY-07-643; DOE/OR/23177-0042
TRN: US0703100
DOE Contract Number:
AC05-06OR23177
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; QUARKS; DETECTION; XI PARTICLES; CEBAF ACCELERATOR; EXCLUSIVE INTERACTIONS

Citation Formats

Mattione, Paul. Kinematic Fitting of Detached Vertices. United States: N. p., 2007. Web. doi:10.2172/903056.
Mattione, Paul. Kinematic Fitting of Detached Vertices. United States. doi:10.2172/903056.
Mattione, Paul. Tue . "Kinematic Fitting of Detached Vertices". United States. doi:10.2172/903056. https://www.osti.gov/servlets/purl/903056.
@article{osti_903056,
title = {Kinematic Fitting of Detached Vertices},
author = {Mattione, Paul},
abstractNote = {The eg3 experiment at the Jefferson Lab CLAS detector aims to determine the existence of the $\Xi_{5}$ pentaquarks and investigate the excited $\Xi$ states. Specifically, the exotic $\Xi_{5}^{--}$ pentaquark will be sought by first reconstructing the $\Xi^{-}$ particle through its weak decays, $\Xi^{-}\to\pi^{-}\Lambda$ and $\Lambda\to\pi^{-}$. A kinematic fitting routine was developed to reconstruct the detached vertices of these decays, where confidence level cuts on the fits are used to remove background events. Prior to fitting these decays, the exclusive reaction $\gamma D\rightarrow pp\pi^{-}$ was studied in order to correct the track measurements and covariance matrices of the charged particles. The $\Lambda\rightarrow p\pi^{-}$ and $\Xi^{-}\to\pi^{-}\Lambda$ decays were then investigated to demonstrate that the kinematic fitting routine reconstructs the decaying particles and their detached vertices correctly.},
doi = {10.2172/903056},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

Thesis/Dissertation:
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