Download or read book Determination of Electron Beam Polarization Using Electron Detector in Compton Polarimeter with Less Than 1 Statistical and Systematic Uncertainty written by Amrendra Narayan and published by . This book was released on 2015 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Q-weak experiment aims to measure the weak charge of proton with a precision of 4.2%. The proposed precision on weak charge required a 2.5% measurement of the parity violating asymmetry in elastic electron - proton scattering. Polarimetry was the largest experimental contribution to this uncertainty and a new Compton polarimeter was installed in Hall C at Jefferson Lab to make the goal achievable. In this polarimeter the electron beam collides with green laser light in a low gain Fabry- Perot Cavity; the scattered electrons are detected in 4 planes of a novel diamond micro strip detector while the back scattered photons are detected in lead tungstate crystals. This diamond micro-strip detector is the first such device to be used as a tracking detector in a nuclear and particle physics experiment. The diamond detectors are read out using custom built electronic modules that include a preamplifier, a pulse shaping amplifier and a discriminator for each detector micro-strip. We use field programmable gate array based general purpose logic modules for event selection and histogramming. Extensive Monte Carlo simulations and data acquisition simulations were performed to estimate the systematic uncertainties. Additionally, the Moller and Compton polarimeters were cross calibrated at low electron beam currents using a series of interleaved measurements. In this dissertation, we describe all the subsystems of the Compton polarimeter with emphasis on the electron detector. We focus on the FPGA based data acquisition system built by the author and the data analysis methods implemented by the author. The simulations of the data acquisition and the polarimeter that helped rigorously establish the systematic uncertainties of the polarimeter are also elaborated, resulting in the first sub 1% measurement of low (~1GeV) electron beam polarization with a Compton electron detector. We have demonstrated that diamond based micro-strip detectors can be used for tracking in a high radiation environment and it has enabled us to achieve the desired precision in the measurement of the electron beam polarization which in turn has allowed the most precise determination of the weak charge of the proton.
Download or read book Determination of Electron Beam Polarization Using Electron Detector in Compton Polarimeter with Less Than 1 Statistical and Systematic Uncertainty written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Q-weak experiment aims to measure the weak charge of proton with a precision of 4.2%. The proposed precision on weak charge required a 2.5% measurement of the parity violating asymmetry in elastic electron - proton scattering. Polarimetry was the largest experimental contribution to this uncertainty and a new Compton polarimeter was installed in Hall C at Jefferson Lab to make the goal achievable. In this polarimeter the electron beam collides with green laser light in a low gain Fabry-Perot Cavity; the scattered electrons are detected in 4 planes of a novel diamond micro strip detector while the back scattered photons are detected in lead tungstate crystals. This diamond micro-strip detector is the first such device to be used as a tracking detector in a nuclear and particle physics experiment. The diamond detectors are read out using custom built electronic modules that include a preamplifier, a pulse shaping amplifier and a discriminator for each detector micro-strip. We use field programmable gate array based general purpose logic modules for event selection and histogramming. Extensive Monte Carlo simulations and data acquisition simulations were performed to estimate the systematic uncertainties. Additionally, the Moller and Compton polarimeters were cross calibrated at low electron beam currents using a series of interleaved measurements. In this dissertation, we describe all the subsystems of the Compton polarimeter with emphasis on the electron detector. We focus on the FPGA based data acquisition system built by the author and the data analysis methods implemented by the author. The simulations of the data acquisition and the polarimeter that helped rigorously establish the systematic uncertainties of the polarimeter are also elaborated, resulting in the first sub 1% measurement of low energy (?1 GeV) electron beam polarization with a Compton electron detector. We have demonstrated that diamond based micro-strip detectors can be used for tracking in a high radiation environment and it has enabled us to achieve the desired precision in the measurement of the electron beam polarization which in turn has allowed the most precise determination of the weak charge of the proton.
Download or read book Compton Scattering Polarimetry for the Determination of the Proton s Weak Charge Through Measurements of the Parity Violating Asymmetry of 1H e E p written by and published by . This book was released on 2016 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model has been a theory with the greatest success in describing the fundamental interactions of particles. As of the writing of this dissertation, the Standard Model has not been shown to make a false prediction. However, the limitations of the Standard Model have long been suspected by its lack of a description of gravity, nor dark matter. Its largest challenge to date, has been the observation of neutrino oscillations, and the implication that they may not be massless, as required by the Standard Model. The growing consensus is that the Standard Model is simply a lower energy effective field theory, and that new physics lies at much higher energies. The Qweak Experiment is testing the Electroweak theory of the Standard Model by making a precise determination of the weak charge of the proton (Qpw). Any signs of "new physics" will appear as a deviation to the Standard Model prediction. The weak charge is determined via a precise measurement of the parity-violating asymmetry of the electron-proton interaction via elastic scattering of a longitudinally polarized electron beam of an un-polarized proton target. The experiment required that the electron beam polarization be measured to an absolute uncertainty of 1%. At this level the electron beam polarization was projected to contribute the single largest experimental uncertainty to the parity-violating asymmetry measurement. This dissertation will detail the use of Compton scattering to determine the electron beam polarization via the detection of the scattered photon. I will conclude the remainder of the dissertation with an independent analysis of the blinded Qweak.
Download or read book Proceedings Of The 29th International Conference On High Energy Physics Ichep 98 In 2 Volumes written by Alan Astbury and published by World Scientific. This book was released on 1999-06-11 with total page 1899 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings consist of plenary rapporteur talks covering topics of major interest to the high energy physics community and parallel sessions papers which describe recent research results and future plans.
Download or read book Compton Scattering Polarimetry for the Determination of the Proton s Weak Charge Through Measurements of the Parity violating Asymmetry of 1H E e P written by Juan Carlos Cornejo and published by . This book was released on 2016 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model has been a theory with the greatest success in describing the fundamental interactions of particles. As of the writing of this dissertation, the Standard Model has not been shown to make a false prediction. However, the limitations of the Standard Model have long been suspected by its lack of a description of gravity, nor dark matter. Its largest challenge to date, has been the observation of neutrino oscillations, and the implication that they may not be massless, as required by the Standard Model. The growing consensus is that the Standard Model is simply a lower energy effective field theory, and that new physics lies at much higher energies. The Qweak Experiment is testing the Electroweak theory of the Standard Model by making a precise determination of the weak charge of the proton (Qpw). Any signs of 0́−new physics0́+ will appear as a deviation to the Standard Model prediction. The weak charge is determined via a precise measurement of the parity-violating asymmetry of the electron-proton interaction via elastic scattering of a longitudinally polarized electron beam of an un-polarized proton target. The experiment required that the electron beam polarization be measured to an absolute uncertainty of 1 %. At this level the electron beam polarization was projected to contribute the single largest experimental uncertainty to the parity-violating asymmetry measurement. This dissertation will detail the use of Compton scattering to determine the electron beam polarization via the detection of the scattered photon. I will conclude the remainder of the dissertation with an independent analysis of the blinded Qweak .
Download or read book Accurate Measurement of the Electron Beam Polarization in JLab Hall A Using Compton Polarimetry written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A major advance in accurate electron beam polarization measurement has been achieved at Jlab Hall A with a Compton polarimeter based on a Fabry-Perot cavity photon beam amplifier. At an electron energy of 4.6 GeV and a beam current of 40 uA, a total relative uncertainty of 1.5% is typically achieved within 40 min of data taking. Under the same conditions monitoring of the polarization is accurate at a level of 1%. These unprecedented results make Compton polarimetry an essential tool for modern parity-violation experiments, which require very accurate electron beam polarization measurements.
Download or read book High Precision Electron Beam Polarization Measurement with Compton Polarimetry at Jefferson Laboratory written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1999, a Compton polarimeter based on a Fabry-Perot cavity to amplify the laser light is operational in the hall A of the Jefferson Laboratory. In 2000, the beam polarization has been continuously measured during N â Delta and Gep experiment providing a relative total uncertainty of 1.4% in 40 mn at 4.5 GeV. These unprecedented results have been obtained thanks to a scattered electron detector which has allowed to determine the response function of the photon calorimeter.
Download or read book From Parity Violation to Hadronic Structure and more written by K. de Jager and published by Springer Science & Business Media. This book was released on 2008-06-21 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the proceedings of the third international workshop on From Parity Violation to Hadronic Structure and More. The many applications of parity violation are way beyond the scope of what Lee and Yang could have imagined fifty years after their proposal. For the physics topics discussed during this workshop, the application of parity violation has become a standard work horse allowing for the extraction of many physics topics in different experiments.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1972 with total page 1264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compton Polarimeter for Qweak Experiment at Jefferson Laboratory written by David Zou and published by . This book was released on 2011 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Qweak experiment at Jefferson Lab aims to make the first precision measurement of the proton's weak charge, QP = 1 - 4 sin 2 9w at Q2 = 0.026GeV 2 . Given the precision goals in the Qweak experiment, the electron beam polarization must be known to an absolute uncertainty of 1%. A new Compton polarimeter has been built and installed in Hall C in order to make this important measurement. Compton polarimetry has been chosen for its ability to deliver continuous on-line measuremnts at high currents necessary for Qweak (up to 180pzA). In this thesis, we collected and analyzed electron beam polarization data using the Qweak Compton polarimeter. Currently, data from the Compton can already be used to calculate preliminary values of experimental physics asymmetries and also the electron beam polarization. These preliminary results are promising indications that Qweak will be able to meet its stated precision goals.
Download or read book 96 Electroweak Interactions and Unified Theories written by J. Thanh Van Tran and published by Atlantica Séguier Frontières. This book was released on 1996 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polarimetery for SuperB written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We provide an overview description of a Compton polarimeter for measuring electron beam polarization near the IR in the Low Energy Ring of SuperB. The polarimeter is designed to achieve 1.0% accuracy. A scheme for measuring the electron beam polarization at SuperB near the IR has been described. The Compton polarimeter has been designed to fit into the existing lattice of the SuperB ring and results in a Compton IP measuring the polarization located where the beam is almost longitudinal with opposite helicity to that at the IR. The polarization at the IR is expected to be determined with an accuracy of ≈1% from the measurement at the Compton IP provided the beam direction at the electron-positron interaction region and the Compton IP are well known and the beam energy is measured to better than 20 MeV. Detailed detector studies are needed to study resolution and acceptance effects on detector analyzing powers, and to determine sensitivity to beam and machine parameters.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1972-04 with total page 1068 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Calorimetry In High Energy Physics Proceedings Of The 7th International Conference written by Elliot Cheu and published by World Scientific. This book was released on 1998-09-22 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers all aspects of particle detection using calorimetric techniques. The emphasis is on methods currently employed in existing detectors, with some articles devoted to techniques under development.
Download or read book First Electron Beam Polarization Measurements with a Compton Polarimeter at Jefferson Laboratory written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A Compton polarimeter has been installed in Hall A at Jefferson Laboratory. This letter reports on the first electron beam polarization measurements performed during the HAPPEX experiment at an electron energy of 3.3 GeV and an average current of 40 muA. The heart of this device is a Fabry-Perot cavity which increased the luminosity for Compton scattering in the interaction region so much that a 1.4% statistical accuracy could be obtained within one hour, with a 3.3% total error.
Download or read book The ELFE Project an Electron Laboratory for Europe written by Jacques Arvieux and published by Compositori. This book was released on 1993 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preliminary Results from Integrating Compton Photon Polarimetry in Hall A of Jefferson Lab written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A wide range of nucleon and nuclear structure experiments in Jefferson Lab's Hall A require precise, continuous measurements of the polarization of the electron beam. In our Compton polarimeter, electrons are scattered off photons in a Fabry-Perot cavity; by measuring an asymmetry in the integrated signal of the scattered photons detected in a GSO crystal, we can make non-invasive, continuous measurements of the beam polarization. Our goal is to achieve 1% statistical error within two hours of running. We discuss the design and commissioning of an upgrade to this apparatus, and report preliminary results for experiments conducted at beam energies from 3.5 to 5.9 GeV and photon rates from 5 to 100 kHz.
