Download or read book A Search for Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment written by Juan Pedro Ochoa-Ricoux and published by Springer Science & Business Media. This book was released on 2011-04-11 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: The centerpiece of the thesis is the search for muon neutrino to electron neutrino oscillations which would indicate a non-zero mixing angle between the first and third neutrino generations (θ13), currently the “holy grail” of neutrino physics. The optimal extraction of the electron neutrino oscillation signal is based on the novel “library event matching” (LEM) method which Ochoa developed and implemented together with colleagues at Caltech and at Cambridge, which improves MINOS’ (Main Injector Neutrino Oscillator Search) reach for establishing an oscillation signal over any other method. LEM will now be the basis for MINOS’ final results, and will likely keep MINOS at the forefront of this field until it completes its data taking in 2011. Ochoa and his colleagues also developed the successful plan to run MINOS with a beam tuned for antineutrinos, to make a sensitive test of CPT symmetry by comparing the inter-generational mass splitting for neutrinos and antineutrinos. Ochoa’s in-depth, creative approach to the solution of a variety of complex experimental problems is an outstanding example for graduate students and longtime practitioners of experimental physics alike. Some of the most exciting results in this field to emerge in the near future may find their foundations in this thesis.

Download or read book A Search for Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment written by and published by . This book was released on 2009 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: We perform a search for v[mu] → ve oscillations, a process which would manifest a nonzero value of the [theta]13 mixing angle, in the MINOS long-baseline neutrino oscillation experiment. The analysis consists of searching for an excess of ve charged-current candidate events over the predicted backgrounds, made mostly of neutral-current events with high electromagnetic content. A novel technique to select electron neutrino events is developed, which achieves an improved separation between the signal and the backgrounds, and which consequently yields a better reach in [theta]13. The backgrounds are predicted in the Far Detector from Near Detector measurements. An excess is observed in the Far Detector data over the predicted backgrounds, which is consistent with the background-only hypothesis at 1.2 standard deviations.

Download or read book New Results for Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment written by and published by . This book was released on 2010 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: MINOS is a long-baseline neutrino oscillation experiment situated along Fermilab's high-intensity NuMI neutrino beam. MINOS has completed an updated search for muon neutrino to electron neutrino transitions, observation of which would indicate a non-zero value for the neutrino mixing angle [theta]13. The present 7 x 102° protons-on-target data set represents more than double the exposure used in the previous analysis. The new result and its implications are presented.

Download or read book Measuring theta Via Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment written by and published by . This book was released on 2011 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the primary goals in neutrino physics at the present moment is to make a measurement of the neutrino oscillation parameter $\theta_$. This parameter, in addition to being unknown, could potentially allow for the introduction of CP violation into the lepton sector. The MINOS long-baseline neutrino oscillation experiment has the ability to make a measurement of this parameter, by looking for the oscillation of muon neutrinos to electron neutrinos between a Near and Far Detector over a distance of 735 km. This thesis discusses the development of an analysis framework to search for this oscillation mode. Two major improvements to pre-existing analysis techniques have been implemented by the author. First, a novel particle ID technique based on strip topology, known as the Library Event Matching (LEM) method, is optimized for use in MINOS. Second, a multiple bin likelihood method is developed to fit the data. These two improvements, when combined, increase MINOS' sensitivity to $\sin^2(2\theta_)$ by 27\% over previous analyses. This thesis sees a small excess over background in the Far Detector. A Frequentist interpretation of the data rules out $\theta_=0$ at 91\%. A Bayesian interpretation of the data is also presented, placing the most stringent upper boundary on the oscillation parameter to date, at $\sin^2(2\theta_)

Download or read book A Study of Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment written by and published by . This book was released on 2009 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: The observation of neutrino oscillations (neutrino changing from one flavor to another) has provided compelling evidence that the neutrinos have non-zero masses and that leptons mix, which is not part of the original Standard Model of particle physics. The theoretical framework that describes neutrino oscillation involves two mass scales ([Delta]matm2 and [Delta]msol2), three mixing angles ([theta]12, [theta]23, and [theta]13) and one CP violating phase ([delta]CP). Both mass scales and two of the mixing angles ([theta]12 and [theta]23) have been measured by many neutrino experiments. The mixing angle [theta]13, which is believed to be very small, remains unknown. The current best limit on [theta]13 comes from the CHOOZ experiment: [theta]13

Download or read book Improved Search for Muon neutrino to Electron neutrino Oscillations in MINOS written by and published by . This book was released on 2011 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report the results of a search for?{sub e} appearance in?{sub {mu}} beam in the MINOS long-baseline neutrino experiment. With an improved analysis and an increased exposure of 8.2 x 102° protons on the NuMI target at Fermilab, they find that 2 sin2 (?23) sin2 (?13)

Download or read book A Measurement of Neutrino Oscillations with Muon Neutrinos in the MINOS Experiment written by and published by . This book was released on 2011 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental evidence has established that neutrino flavor states evolve over time. A neutrino of a particular flavor that travels some distance can be detected in a different neutrino flavor state. The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline experiment that is designed to study this phenomenon, called neutrino oscillations. MINOS is based at Fermilab near Chicago, IL, and consists of two detectors: the Near Detector located at Fermilab, and the Far Detector, which is located in an old iron mine in Soudan, MN. Both detectors are exposed to a beam of muon neutrinos from the NuMI beamline, and MINOS measures the fraction of muon neutrinos that disappear after traveling the 734 km between the two detectors. One can measure the atmospheric neutrino mass splitting and mixing angle by observing the energy-dependence of this muon neutrino disappearance. MINOS has made several prior measurements of these parameters. Here I describe recently-developed techniques used to enhance our sensitivity to the oscillation parameters, and I present the results obtained when they are applied to a dataset that is twice as large as has been previously analyzed. We measure the mass splitting ?m232 = (2.32-0.08+0.12) x 10-3 eV2/c4 and the mixing angle sin2(2?32) > 0.90 at 90% C.L. These results comprise the world's best measurement of the atmospheric neutrino mass splitting. Alternative disappearance models are also tested. The neutrino decay hypothesis is disfavored at 7.2? and the neutrino quantum decoherence hypothesis is disfavored at 9.0?.

Download or read book Observing Muon Neutrino to Electron Neutrino Oscillations in the NO nu A Experiment written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Search for Muon Neutrino to Electron Neutrino Oscillations at m2 0 1 EV2 written by and published by . This book was released on 2007 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evidence is compelling that neutrinos undergo flavor change as they propagate. In recent years, experiments have observed this phenomenon of neutrino oscillations using disparate neutrino sources: the sun, fission reactors, accelerators, and secondary cosmic rays. The standard model of particle physics needs only simple extensions - neutrino masses and mixing - to accommodate all neutrino oscillation results to date, save one. The 3.8?-significant $ar{v}$e excess reported by the LSND collaboration is consistent with $ar{v}$? →$ar{v}$e oscillations with a mass-squared splitting of ?m2 ̃1 eV2. This signal, which has not been independently verified, is inconsistent with other oscillation evidence unless more daring standard model extensions (e.g. sterile neutrinos) are considered.

Download or read book A Search for Muon Neutrino to Electron Neutrino Oscillations in the Appearance Mode written by David Works and published by . This book was released on 1995 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Search for Muon Neutrino to Electron Neutrino Oscillations at Delta m 2 0 1 EV 2 written by and published by . This book was released on 2007 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evidence is compelling that neutrinos undergo flavor change as they propagate. In recent years, experiments have observed this phenomenon of neutrino oscillations using disparate neutrino sources: the sun, fission reactors, accelerators, and secondary cosmic rays. The standard model of particle physics needs only simple extensions - neutrino masses and mixing - to accommodate all neutrino oscillation results to date, save one. The 3.8[sigma]-significant {bar {nu}}{sub e} excess reported by the LSND collaboration is consistent with {bar {nu}}{sub {mu}} →{bar {nu}}{sub e} oscillations with a mass-squared splitting of [Delta]m2 ≈ 1 eV2. This signal, which has not been independently verified, is inconsistent with other oscillation evidence unless more daring standard model extensions (e.g. sterile neutrinos) are considered.

Download or read book A Study of Muon Neutrino Disappearance in the MINOS Detectors and the NuMI Beam written by and published by . This book was released on 2010 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is now substantial evidence that the proper description of neutrino involves two representations related by the 3 x 3 PMNS matrix characterized by either distinct mass or flavor. The parameters of this mixing matrix, three angles and a phase, as well as the mass differences between the three mass eigenstates must be determined experimentally. The Main Injector Neutrino Oscillation Search experiment is designed to study the flavor composition of a beam of muon neutrinos as it travels between the Near Detector at Fermi National Accelerator Laboratory at 1 km from the target, and the Far Detector in the Soudan iron mine in Minnesota at 735 km from the target. From the comparison of reconstructed neutrino energy spectra at the near and far location, precise measurements of neutrino oscillation parameters from muon neutrino disappearance and electron neutrino appearance are expected. It is very important to know the neutrino flux coming from the source in order to achieve the main goal of the MINOS experiment: precise measurements of the atmospheric mass splitting.

Download or read book Neutrino Mass written by Guido Altarelli and published by Springer. This book was released on 2004-02-24 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews the current state of knowledge of neutrino masses and the related question of neutrino oscillations. After an overview of the theory of neutrino masses and mixings, detailed accounts are given of the laboratory limits on neutrino masses, astrophysical and cosmological constraints on those masses, experimental results on neutrino oscillations, the theoretical interpretation of those results, and theoretical models of neutrino masses and mixings. The book concludes with an examination of the potential of long-baseline experiments. This is an essential reference text for workers in elementary-particle physics, nuclear physics, and astrophysics.

Download or read book Measurement of Electron Neutrino Appearance with the MINOS Experiment written by and published by . This book was released on 2009 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: MINOS is a long-baseline two-detector neutrino oscillation experiment that uses a high intensity muon neutrino beam to investigate the phenomena of neutrino oscillations. By measuring the neutrino interactions in a detector near the neutrino source and again 735 km away from the production site, it is possible to probe the parameters governing neutrino oscillation. The majority of the [nu]{sub {mu}} oscillate to [nu]{sub {tau}} but a small fraction may oscillate instead to [nu]{sub e}. This thesis presents a measurement of the [nu]{sub e} appearance rate in the MINOS far detector using the first two years of exposure. Methods for constraining the far detector backgrounds using the near detector measurements is discussed and a technique for estimating the uncertainty on the background and signal selection are developed. A 1.6[sigma] excess over the expected background rate is found providing a hint of [nu]{sub e} appearance.

Download or read book Electron Neutrino Appearance in the MINOS Experiment written by and published by . This book was released on 2010 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS experiment is a long-baseline neutrino oscillation experiment which sends a high intensity muon neutrino beam through two functionally identical detectors, a Near detector at the Fermi National Accelerator Laboratory in Illinois, 1km from the beam source, and a Far detector, 734km away, in the Soudan Mine in Minnesota. MINOS may be able to measure the neutrino mixing angle parameter sin2 2[theta] 13 for the rst time. Detector granularity, however, makes it very hard to distinguish any e appearance signal events characteristic of a non-zero value of [theta] 13 from background neutral current (NC) and short-track v[mu] charged current (CC) events. Also, uncertainties in the hadronic shower modeling in the kinematic region characteristic of this analysis are relatively large. A new data-driven background decomposition method designed to address those issues is developed and its results presented. By removing the long muon tracks from v[mu]-CC events, the Muon Removed Charge Current (MRCC) method creates independent pseudo-NC samples that can be used to correct the MINOS Monte Carlo to agree with the high-statistics Near detector data and to decompose the latter into components so as to predict the expected Far detector background. The MRCC method also provides an important cross-check in the Far detector to test the background in the signal selected region. MINOS finds a 1.0-1.5 [sigma] ve-CC excess above background in the Far detector data, depending on method used, for a total exposure of 3.14 x 1020 protons-on-target. Interpreting this excess as signal, MINOS can set limits on sin2 2[theta] 13. Using the MRCC method, MINOS sets a limit of sin2 2 [theta] 13

Download or read book Muon Neutrino to Electron Neutrino Oscillation in NO nu A written by and published by . This book was released on 2015 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOvA is a long-baseline neutrino oscillation experiment optimized for electron neu- trino (e) appearance in the NuMI beam, a muon neutrino ($\nu$[mu]) source at Fermilab. It consists of two functionally identical, nearly fully-active liquid-scintillator tracking calorimeters. The near detector (ND) at Fermilab is used to study the neutrino beam spectrum and composition before oscillation, and measure background rate to the $\nu$e appearance search. The far detector, 810 km away in Northern Minnesota, observes the oscillated beam and is used to extract oscillation parameters from the data. NO$\nu$ A's long baseline, combined with the ability of the NuMI beam to operate in the anti- neutrino mode, makes NO$\nu$ A sensitive to the last unmeasured parameters in neutrino oscillations- mass hierarchy, CP violation and the octant of mixing angle 23. This thesis presents the search for e appearance in the first data collected by the NO A detectors from October 2013 till May 2015. Studies of the NuMI neutrino data collected in the NO A near detector are also presented, which show large discrepancies between the ND simulation and data. Muon- removed electron (MRE) events, constructed by replacing the muon in $\nu$[mu] charged cur- rent interactions by a simulated electron, are used to correct the far detector $\nu$e appearance prediction for these discrepancies. In the analysis of the first data, a total of 6 e candidate events are observed in the far detector on a background of 1, a 3.46 [sigma] excess, which is interpreted as strong evidence for e appearance. The results are consistent with our expectation, based on constraints from other neutrino oscillation experiments. The result presented here differs from the officially published $\nu$e appearance result from the NO A experiment where the systematic error is assumed to cover the MRE correction.

Download or read book A Sterile Neutrino Search with the MINOS Experiment written by and published by . This book was released on 2010 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS experiment is a long-baseline neutrino oscillation experiment in the the NuMI beamline at Fermilab, USA. Using a near detector at 1 km distance from the neutrino production target, and a far detector at 735 km from the target, it is designed primarily to measure the disappearance of muon neutrinos. This thesis presents an analysis using MINOS data of the possibility of oscil- lation of the neutrinos in the NuMI beam to a hypothetical sterile flavour, which would have no Standard Model couplings. Such oscillations would result in a deficit in the neutral current interaction rate in the MINOS far detector relative to the expectation derived from the near detector data. The method used to identify neutral current and charged current events in the MINOS detectors is described and a new method of predicting and fitting the far detector spectrum presented, along with the effects of systematic uncertainties on the sterile neutrino oscillation analysis. Using this analysis, the fraction f{sub s} of the disappearing neutrinos that go to steriles is constrained to be below 0.15 at the 90% confidence level in the absence of electron neutrino appearance in the NuMI beam. With electron appearance at the CHOOZ limit, f{sub s}