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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Identifying muons for neutrino oscillation and cross section experiments

Ratchford, Jasmine Star Yuko Ma 17 July 2012 (has links)
Neutrinos (v) are interesting for many reasons; they are the only fundamental fermions which are electrically neutral; their mass is orders of magnitude smaller than the lightest charged lepton, the electron; and their solely weak interactions make them an excellent probe of the weak nuclear force. However, one of the most interesting aspects of neutrinos is that, unlike their charged lepton partners, neutrino mass and flavor eigenstates are not the same. All leptons possess 'lepton flavor', a property which is conserved in neutrino interactions. However, because of the difference in the mass and weak eigenstates of neutrinos, a quantum-interference effect is seen in the time evolution of neutrinos. This results in energy and distance dependent oscillations of the neutrino's lepton flavor called 'neutrino oscillations'. The MINOS experiment (Main Injector Neutrino Oscillation Search) was designed to measure the neutrino oscillation parameters, [Delta]m²₃₂ and sin²(2[theta]₃₂). MINOS is composed of two detectors located on a 'beam' of v[subscript mu]s. The MINOS Near Detector is located at Fermilab, and the Far Detector is located at the Soudan Mine in Minnesota, 734 km after the Near Detector. The MINERvA experiment (Main Injector Neutrino Experiment for v - A) is a neutrino experiment placed directly in front of the MINOS Near Detector. MINERvA's goal is to make precision measurements of neutrino cross sections. This will help with uncertainties in oscillation measurements, such as MINOS' at low energy. Although lepton flavor is conserved in neutrino interactions, the final state lepton can be a charged lepton ('charged current' interactions) or a neutrino ('neutral current' interactions) of a particular flavor. The identification of charged current ν[subscript mu] interactions through the identification of a muon in the final state is a critical component to both neutrino oscillation and cross section measurements; neutral current events are a background to the oscillation signal because the properties of the incoming neutrino cannot be determined. Such identification is particularly difficult and important for low-energy neutrino events. In this thesis, we will discuss improvements to the MINOS charged current identification at low energies, studies to estimate the effect of the neutral current background on the measurement of the oscillation parameters, and the aspects of muon identification which are similar for the MINOS and MINERvA experiments. In 2010, the MINOS experiment released a measurement of the oscillation parameters based on 7.32x10²⁰POT. The results were [Delta]m²₃₂ = 2.32⁺⁰̇¹²[subscript 0.08] x 10³eV², and sin²(2[theta]₃₂) > 0.90(90%,C.L.). This is the best measurement of the oscillation parameter, [Delta]m²₃₂, and a competitive measurement of sin²(2[theta]₃₂). The improvements to the charged current event selection helped MINOS observe a complete oscillation in neutrino energy. / text
2

Measurement of the muon neutrino charged current pion production cross-section on water using the T2K near detector

Cremonesi, Linda January 2015 (has links)
T2K is a long baseline neutrino experiment which uses a beam of muon neutrinos, produced at J-PARC and detected at Super-Kamiokande, to study the neutrino oscillation parameters. The measurement of cross-sections in the T2K energies can constrain the uncertainties on the model predictions and help the oscillation analyses reach the necessary sensitivity to measure CP violation in the lepton sector. This thesis describes the measurement of the CC1 + cross-section in water using Run II-IV T2K data. The T2K near detector, ND280, is used to select a sample of CC1 + events having vertices in the water layers of the downstream ne-grained detector (FGD). The Time Projection Chambers (TPC) are used for the particle identi cation and to measure their momenta. The Electromagnetic Calorimeters (ECals) are used to reject events that produce electromagnetic showers coming from neutral pions. A Bayesian unfolding method with background subtraction and two control samples is used to extract the cross-section. The control samples constrain the background coming from interactions on carbon and deep inelastic scattering. The single di erential cross-section is presented as a function of the muon kinematics, the pion kinematics, the angle between the muon and the pion, and the reconstructed neutrino energy. A future long baseline experiment between J-PARC and Hyper-Kamiokande is presented as a natural continuation to the T2K experiment. Hyper- Kamiokande will be a next generation water Cherenkov detector with a total ( ducial) mass of 0.99 (0.56) million metric tons. A total exposure of 7.5MW 107 sec integrated beam power will lead to the measurement of CP to better than 19 degrees for all possible values of CP . CP violation in the lepton sector could be established at better than 3 (5 ) for 76% (58%) of the CP parameter space.
3

A search for nu(mu) to nu(e) oscillations in the NOMAD experiment

Godley, Andrew January 2001 (has links)
The NOMAD experiment is a neutrino oscillation experiment, capable of identifying \nm, \nmb, \nel, \neb\ and \nt\ for use in oscillation analyses. A search for \mutoe\ oscillations is conducted, emphasising the development of two separate beam simulators, to provide the background, (no oscillation), \nel\ signal. Both beam descriptions include fits to the results of the SPY experiment that measured hadron production from a 450~GeV proton beam on beryllium target. An independent analysis of the raw SPY data to produce the particle yield is reported. A series of criteria are described for the selection and classification of neutrino events. These produce the data samples necessary for both tuning the beam simulation and determining the oscillation signal. The development of a GEANT and FLUKA based Monte Carlo beam simulator is presented, providing good agreement to the measured neutrino beam. This simulation method has sizeable variations depending on the beamline geometry, which is not known precisely. This causes large systematic errors. An empirical parametrisation is proposed and used for the first time in a NOMAD oscillation search. It uses the measured neutrino spectra at NOMAD, except the \nel, to infer the meson production at the target, and then predict the \nel\ spectrum. This method has good agreement with the data and is also insensitive to alterations of the beamline geometry, resulting in much smaller systematic errors. The reduction of the systematic errors allows the \mutoe\ oscillations search to be performed with much greater precision. Comparisons of the \nel/\nm\ ratio between the empirical parametrisation and data yields no evidence for \mutoe\ oscillations, setting a limit on the mixing parameter, $sin^2(2 \theta) &lt 1.9 \times 10^{-3} \mbox{(90\% CL)}$ at high $\Delta m^2$. The present sensitivity of the analysis on the mixing parameter is 0.0017.
4

A search for nu(mu) to nu(e) oscillations in the NOMAD experiment

Godley, Andrew January 2001 (has links)
The NOMAD experiment is a neutrino oscillation experiment, capable of identifying \nm, \nmb, \nel, \neb\ and \nt\ for use in oscillation analyses. A search for \mutoe\ oscillations is conducted, emphasising the development of two separate beam simulators, to provide the background, (no oscillation), \nel\ signal. Both beam descriptions include fits to the results of the SPY experiment that measured hadron production from a 450~GeV proton beam on beryllium target. An independent analysis of the raw SPY data to produce the particle yield is reported. A series of criteria are described for the selection and classification of neutrino events. These produce the data samples necessary for both tuning the beam simulation and determining the oscillation signal. The development of a GEANT and FLUKA based Monte Carlo beam simulator is presented, providing good agreement to the measured neutrino beam. This simulation method has sizeable variations depending on the beamline geometry, which is not known precisely. This causes large systematic errors. An empirical parametrisation is proposed and used for the first time in a NOMAD oscillation search. It uses the measured neutrino spectra at NOMAD, except the \nel, to infer the meson production at the target, and then predict the \nel\ spectrum. This method has good agreement with the data and is also insensitive to alterations of the beamline geometry, resulting in much smaller systematic errors. The reduction of the systematic errors allows the \mutoe\ oscillations search to be performed with much greater precision. Comparisons of the \nel/\nm\ ratio between the empirical parametrisation and data yields no evidence for \mutoe\ oscillations, setting a limit on the mixing parameter, $sin^2(2 \theta) &lt 1.9 \times 10^{-3} \mbox{(90\% CL)}$ at high $\Delta m^2$. The present sensitivity of the analysis on the mixing parameter is 0.0017.
5

JLab E12-14-012 (e,e'p) cross section measurements for Ar and Ti

Gu, Linjie 01 July 2021 (has links)
In recent years, many high precision experiments were carried aiming to improve the accuracy on the measurements of the neutrino oscillation parameters. One of the main source of uncertainty for neutrino oscillation experiments is due to the lack of a comprehensive theoretical description of neutrino-nucleus interactions. The US Deep Underground Neutrino Oscillation Experiments (DUNE) will deploy a series of detectors using Liquid Argon Time Projection Chambers (LArTPCs). A fully consistent parameter-free theoretical neutrino-nucleus scattering model on argon does not exist. The first step towards constructing a nuclear model will be to determine the energy and momentum distribution of protons and neutrons inside the argon nucleus. The JLab E12-14-012 experiment performed at Jefferson Laboratory in Newport News, Virginia, ran in 2017 and will provide such measurements in Argon and Titanium using electron scattering (e,e'p). The data collected by the experiment covers a wide range of energy transfers and also includes several other targets like aluminum and carbon. This Ph.D. thesis will present details of the JLab E12-14-012 experiment, together with first data analysis results of the exclusive (e,e'p) data on Argon and Titanium. / Doctor of Philosophy / Neutrino, a tiny, nearly massless particle was discovered about one hundred years ago. Neutrinos are everywhere around us. If you put your hands under the sunlight, each second, there will be about one billion neutrinos pass through them. As the second most abundant particle in the universe, it is extremely important to study neutrinos as they affect many fundamental aspects of our lives. For examples, neutrinos could help us study the nucleons' structure, and how the matter evolved from one particle to many. Since neutrinos are produced in nuclear fusion processes from the sun and stars, we could also understand the sun and universe better by studying the property of neutrinos. Neutrinos have three flavors, and they could change flavors through neutrino oscillation. Measuring the neutrino oscillation parameters is one of the priority tasks for the physics society. Lots of experiments were carried aiming to enhance the understanding of neutrinos and improve the neutrino oscillation measurements accuracy. The most exciting and famous one is the Deep Underground Neutrino Experiment (DUNE) that will be carried in Fermilab. DUNE is an accelerator based experiment that will use Argon as the neutrino target to study the neutrino oscillation. In order to improve the measurement accuracy of the oscillation parameters for the DUNE, a well defined theoretical model for neutrino interaction on Argon is needed. Thus, the JLab E12-14-012 experiment was performed in Hall A at Jefferson Lab in Newport, News, VA to help people get ready for this through electron scattering. The primary goal of this experiment is to measure the electron-nucleus interaction through (e,e$^\prime$p) reactions and further develop a electron-nucleus model to be used in the future neutrino experiments. This thesis will present an overview of the experimental setup and results from the data analysis.
6

Study of antineutrino oscillations using accelerator and atmospheric data in MINOS

Cao, Son Van 17 July 2014 (has links)
The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline experiment that was built for studying the neutrino oscillation phenomena. The MINOS experiment uses high intensity muon neutrino and antineutrino beams created by Neutrinos at the Main Injector facility (NuMI) at the Fermi National Accelerator Laboratory (Fermilab). Neutrino interactions are recorded by two sampling steel-scintillator tracking calorimeters: 0.98 kton Near Detector at Fermilab, IL and 5.4 kton Far Detector at the Soudan Underground Laboratory, MN. These two detectors are functionally identical, which helps to reduce the systematic uncertainties in the muon neutrino and antineutrino disappearance measurements. The Near Detector, located 1.04 km from the neutrino production target, is used to measure the initial beam composition and neutrino energy proximal to the neutrino source. The collected data at the Near Detector is then used to predict energy spectrum in the Far Detector. By comparing this prediction to collected data at the Far Detector, which is 735 km away from the target, it enables a measurement of a set of parameters that govern the neutrino oscillation phenomenon. The flexibility of the NuMI beam configuration and the magnetization of the MINOS detectors facilitate the identification of v[subscript mu] and v̄[subscript mu] charged-current interactions on an event-by-event basis. This enables one to measure neutrino and antineutrino oscillation parameters independently and therefore allows us to test the CPT symmetry in the lepton sector. To enhance the sensitivity of the oscillation parameters measurement, a number of techniques have been implemented. Event classification, shower energy estimation and energy resolution bin fitting, which are described in this dissertation, are three of these techniques. Moreover, the most stringent constraints on oscillation parameters can be achieved by combining multiple data sets. This dissertation reports the measurement of antineutrino oscillation parameters using the complete MINOS accelerator and atmospheric data set of charged-current v̄[subscript mu] events. / text
7

OPERA -First Beam Results-

NAKAMURA, M. 21 February 2008 (has links)
No description available.
8

Using Quasi-elastic Events to Measure Neutrino Oscillations with MINOS Detectors in the NuMI Neutrino Beam

Watabe, Masaki 2010 May 1900 (has links)
MINOS (Main Injector Neutrino Oscillation Search) experiment has been designed to search for a change in the avor composition of a beam of muon neutrinos as they travel between the Near Detector at Fermi National Accelerator Laboratory and the Far Detector in the Soudan mine in Minnesota, 735 km from the target. The MINOS oscillation analysis is mainly performed with the charged current (CC) events and sensitive to constrain high-delta m2 values. However, the quasi-elastic (QEL) charged current interaction is dominant in the energy region important to access low-delta m2 values. For further improvement, the QEL oscillation analysis is performed in this dissertation. A data sample based on a total of 2.50 x 1020 POT is used for this analysis. In summary, 55 QEL-like events are observed at the Far detector while 87.06 +/- 13.17 (syst:) events are expected with null oscillation hypothesis. These data are consistent with vm disappearance via oscillation with delta m2 = 2.10 +/- 0.37 (stat:) +/- 0.24 (syst:) eV2 and the maximal mixing angle.
9

Measurement of the (e,e') cross section for 12C, 48Ti, 27Al and 40Ar

Dai, Hongxia 25 September 2019 (has links)
In the upcoming deep underground neutrino experiment (DUNE), Liquid Argon Time Projection Chambers (LArTPCs) will be used as the detector technology, and argon will be used as the nuclear target. In order to reduce the systematic uncertainties on the extracted oscillation parameters, a more precise description of the argon nuclear structure is needed. Electron scattering has been one of the most powerful methods of studying the nuclear structure of a target. Therefore we performed an electron scattering experiment E12-14- 012 in Hall A at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). In the E12-14-012 experiment, we collected data for the inclusive (e,e′) and exclusive (e,e′p) processes for a variety of targets (argon, titanium, aluminum, carbon) at a wide range of kinematics. This thesis presents the measurements of the double differential cross sections for carbon, titanium, aluminum and argon at beam energy E = 2.222 GeV and scattering angle θ = 15.541◦ / Doctor of Philosophy / In the upcoming deep underground neutrino experiment (DUNE), Liquid Argon Time Projection Chambers (LArTPCs) will be used as the detector technology, and argon will be used as the nuclear target. In order to reduce the systematic uncertainties on the extracted oscillation parameters, a more precise description of the argon nuclear structure is needed. Electron scattering has been one of the most powerful methods of studying the nuclear structure of a target. Therefore we performed an electron scattering experiment E12-14- 012 in Hall A at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). In the E12-14-012 experiment, we collected data for the inclusive (e,e′ ) and exclusive (e,e′p) processes for a variety of targets (argon, titanium, aluminum, carbon) at a wide range of kinematics. This thesis presents the measurements of the double differential cross sections for carbon, titanium, aluminum and argon at beam energy E = 2.222 GeV and scattering angle θ = 15.541◦ .
10

A precision measurement of ν_μ disappearance in the T2K experiment

Dealtry, Thomas J. January 2014 (has links)
T2K is a long-baseline accelerator neutrino oscillation experiment using the high-intensity ν_μ beam produced at J-PARC. Sitting 295 km away, the giant Super-Kamiokande detector, a 50 kt water tank instrumented with 11,129 photosensitive detectors, sees a narrow band beam peaked at 600 MeV. The baseline to energy ratio is finely tuned for studying neutrino oscillations at the atmospheric neutrino squared-mass splitting. The beam is also sampled 280m downstream of the neutrino production target by a series of finely segmented solid scintillator and time projection chamber detectors. Observing changes in the neutrino beam between the two detectors allows oscillation parameters to be accurately extracted. A ν_μ-disappearance analysis was performed on the combined T2K Run 1+2+3+4 dataset, corresponding to integrated J-PARC neutrino beam exposure of 6.57x10<sup>20</sup> POT, in a framework of three active neutrino flavour oscillations including matter effects in constant-density matter. The observed reconstructed energy spectrum of 1 μ-like ring events was fitted, and separate fits were made for the normal and the inverted mass hierarchies.

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