You need JavaScript to view this

Two-photon physics and online beam monitoring using the DELPHI detector at LEP

Abstract

This thesis is based on work done during 1989-1993 using the DELPHI detector at LEP, which is summarized in five articles. It consists of three main parts. The first part describes the Very Small Angle Tagger (VSAT), which is a sub-detector of the DELPHI detector at LEP. It consists of four silicon-tungsten electromagnetic calorimeter modules having a silicon strip planes for position determination. The modules are placed adjacent to the beam pipe, at {+-}7.7 m from the interaction point and after superconducting quadrupole magnets, allowing the detection of electrons in a polar angle range of 4 to 13 mrad. The second part is devoted to two-photon physics at DELPHI, with strong emphasis on a VSAT single-tagged event analysis. Here is shown, for the first time, evidence of hard scattering processes in single-tagged two-photon collisions. A QCD Resolved Photon Contribution (QCD-RPC) model is introduced. Data is then seen to be well described by a full VDM+(QCD-RPC) model. Different parton density functions are compared with data. The third part first describes the system for online monitoring of LEP beam background and luminosity at the DELPHI interaction point. Details are given of contributing sub-detector signals and program structure. Then follows a description of  More>>
Authors:
Publication Date:
Sep 06, 1994
Product Type:
Thesis/Dissertation
Report Number:
LUNFD6-NFFL-7089(1994)
Reference Number:
SCA: 662300; 440100; PA: AIX-26:007041; EDB-95:010888; SN: 95001299520
Resource Relation:
Other Information: TH: Doctoral Diss. (FD).; PBD: 6 Sep 1994
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; REAL TIME SYSTEMS; BEAM MONITORING; BEAM LUMINOSITY; BEAM SEPARATORS; BEAMS; ELECTRON-POSITRON COLLISIONS; HADRONS; LEP STORAGE RINGS; LEPTONS; PHOTONS; 662300; 440100; SPECIFIC INTERACTIONS, DECAYS AND PROCESSES; RADIATION INSTRUMENTATION
OSTI ID:
10102817
Research Organizations:
Lund Univ. (Sweden). Dept. of Physics
Country of Origin:
Sweden
Language:
English
Other Identifying Numbers:
Other: ON: DE95610288; ISBN 91-628-1388-9; TRN: SE9400183007041
Availability:
OSTI; NTIS; INIS
Submitting Site:
SWDN
Size:
47 p.
Announcement Date:
Jun 30, 2005

Citation Formats

Bjarne, J. Two-photon physics and online beam monitoring using the DELPHI detector at LEP. Sweden: N. p., 1994. Web.
Bjarne, J. Two-photon physics and online beam monitoring using the DELPHI detector at LEP. Sweden.
Bjarne, J. 1994. "Two-photon physics and online beam monitoring using the DELPHI detector at LEP." Sweden.
@misc{etde_10102817,
title = {Two-photon physics and online beam monitoring using the DELPHI detector at LEP}
author = {Bjarne, J}
abstractNote = {This thesis is based on work done during 1989-1993 using the DELPHI detector at LEP, which is summarized in five articles. It consists of three main parts. The first part describes the Very Small Angle Tagger (VSAT), which is a sub-detector of the DELPHI detector at LEP. It consists of four silicon-tungsten electromagnetic calorimeter modules having a silicon strip planes for position determination. The modules are placed adjacent to the beam pipe, at {+-}7.7 m from the interaction point and after superconducting quadrupole magnets, allowing the detection of electrons in a polar angle range of 4 to 13 mrad. The second part is devoted to two-photon physics at DELPHI, with strong emphasis on a VSAT single-tagged event analysis. Here is shown, for the first time, evidence of hard scattering processes in single-tagged two-photon collisions. A QCD Resolved Photon Contribution (QCD-RPC) model is introduced. Data is then seen to be well described by a full VDM+(QCD-RPC) model. Different parton density functions are compared with data. The third part first describes the system for online monitoring of LEP beam background and luminosity at the DELPHI interaction point. Details are given of contributing sub-detector signals and program structure. Then follows a description of the VSAT online monitoring program (VSAT-MONITOR). A good agreement is found between the VSAT-MONITOR estimates of luminosity and beam spot and those of other detectors. Finally, results are presented of VSAT measurements of a LEP beam separation scan. 75 refs, figs.}
place = {Sweden}
year = {1994}
month = {Sep}
}