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 A Study of Muon Neutrino Disappearance with the MINOS Detectors and the NuMI Neutrino Beam written by John Stuart Marshall and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Muon Neutrino Disappearance with the MINOS Detectors and the NuMI Neutrino Beam written by and published by . This book was released on 2008 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the results of an analysis of v[mu] disappearance with the MINOS experiment, which studies the neutrino beam produced by the NuMI facility at Fermi National Accelerator Laboratory. The rates and energy spectra of charged current v[mu] interactions are measured in two similar detectors, located at distances of 1 km and 735 km along the NuMI beamline. The Near Detector provides accurate measurements of the initial beam composition and energy, while the Far Detector is sensitive to the effects of neutrino oscillations. The analysis uses data collected between May 2005 and March 2007, corresponding to an exposure of 2.5 x 1020 protons on target. As part of the analysis, sophisticated software was developed to identify muon tracks in the detectors and to reconstruct muon kinematics. Events with reconstructed tracks were then analyzed using a multivariate technique to efficiently isolate a pure sample of charged current v[mu] events. An extrapolation method was also developed, which produces accurate predictions of the Far Detector neutrino energy spectrum, based on data collected at the Near Detector. Finally, several techniques to improve the sensitivity of an oscillation measurement were implemented, and a full study of the systematic uncertainties was performed. Extrapolating from observations at the Near Detector, 733 ± 29 Far Detector events were expected in the absence of oscillations, but only 563 events were observed. This deficit in event rate corresponds to a significance of 4.3 standard deviations. The deficit is energy dependent and clear distortion of the Far Detector energy spectrum is observed. A maximum likelihood analysis, which fully accounts for systematic uncertainties, is used to determine the allowed regions for the oscillation parameters and identifies the best fit values as [Delta]m$2\atop{32}$ = 2.29$+0.14\atop{-0.14}$ x 10-3 eV2 and sin2 2[theta]23> 0.953 (68% confidence level). The models of neutrino decoherence and decay are disfavored at the 5.0[sigma] and 3.2[sigma] levels respectively, while the no oscillation model is excluded at the 9.4[sigma] level.
Download or read book A Measurement of Muon Neutrino Disappearance with the MINOS Detectors and NuMI Beam written by Rustem Ospanov and published by . This book was released on 2008 with total page 560 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. The neutrino beam is produced by the NuMI facility at Fermilab, Batavia, Illinois, and is observed at near and far detectors placed 734 km apart. The neutrino interactions in the near detector are used to measure the initial muon neutrino flux. The vast majority of neutrinos travel through the near detector and Earth matter without interactions. A fraction of muon neutrinos oscillate into other flavors resulting in the disappearance of muon neutrinos at the far detector. This thesis presents a measurement of the muon neutrino oscillation parameters in the framework of the two-neutrino oscillation hypothesis.
Download or read book Observation of Muon Neutrino Disappearance with the MINOS Detectors and the NuMI Neutrino Beam written by and published by . This book was released on 2006 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: This letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current [nu]{sub {mu}} interactions are compared in two detectors located along the beam axis at distances of 1 km and 735 km. With 1.27 x 102° 120GeV protons incident on the NuMI target, 215 events with energies below 30GeV are observed at the Far Detector, compared to an expectation of 336 ± 14.4 events. The data are consistent with [nu]{sub {mu}} disappearance via oscillations with.
Download or read book Observation of Disappearance of Muon Neutrinos in the NuMI Beam written by and published by . This book was released on 2008 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the v[mu] → v[tau] oscillation hypothesis and measure precisely [Delta]m232 and sin22[theta]23 oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the beam is measured at two locations, one close to the source and the other 735 km down-stream in the Soudan Mine Underground Laboratory in northern Minnesota. The precision measurement of the oscillation parameters requires an accurate prediction of the neutrino flux at the Far Detector. This thesis discusses the calculation of the neutrino flux at the Far Detector and its uncertainties. A technique that uses the Near Detector data to constrain the uncertainties in the calculation of the flux is described. The data corresponding to an exposure of 2.5 x 1020 protons on the NuMI target is presented and an energy dependent disappearance pattern predicted by neutrino oscillation hypotheses is observed in the Far Detector data. The fit to MINOS data, for given exposure, yields the best fit values for [Delta]m$2\atop{23}$ and sin2 2[theta]23 to be (2.38$+0.20\atop{-0.16}$) x 10-3 eV2/c4and 1.00-0.08, respectively.
Download or read book Observation of Disappearance of Muon Neutrinos in the NuMI Beam written by Žarko Pavlović and published by . This book was released on 2008 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the v[subscript mu] 2!v[subscript tau] oscillation hypothesis and measure precisely [Delta]m[superscript 2 subscript 23] and sin2 2[theta subscript 23] oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the beam is measured at two locations, one close to the source and the other 735 km downstream in the Soudan Mine Underground Laboratory in northern Minnesota. The precision measurement of the oscillation parameters requires an accurate prediction of the neutrino flux at the Far Detector. This thesis discusses the calculation of the neutrino flux at the Far Detector and its uncertainties. A technique that uses the Near Detector data to constrain the uncertainties in the calculation of the flux is described. The data corresponding to an exposure of 2.5×1020 protons on the NuMI target is presented and an energy dependent disappearance pattern predicted by neutrino oscillation hypotheses is observed in the Far Detector data. The fit to MINOS data, for given exposure, yields the best fit values for [Delta]m[superscript 2 subscript 23] and sin2 2[theta subscript 23] to be (2.38[superscript +0.20, subscript -0.16] x 10−3eV2/c4 and 1.00[subscript -0.08], respectively.
Download or read book Measuring the Disappearance of Muon Neutrinos with the MINOS Detector written by and published by . This book was released on 2013 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: MINOS is a long baseline neutrino oscillation experiment. It measures the flux from the predominately muon neutrino NuMI beam first 1 km from beam start and then again 735 km later using a pair of steel scintillator tracking calorimeters. The comparison of measured neutrino energy spectra at our Far Detector with the prediction based on our Near Detector measurement allows for a measurement of the parameters which define neutrino oscillations. This thesis will describe the most recent measurement of muon neutrino disappearance in the NuMI muon neutrino beam using the MINOS experiment.
Download or read book Observation of Deficit in NuMI Neutrino induced Rock and Non fiducial Muons in MINOS Far Detector and Measurement of Neutrino Oscillation Parameters written by and published by . This book was released on 2007 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS (Main Injector Neutrino Oscillation Search) experiment has observed muon neutrino disappearance consistent with the oscillation hypothesis tested by Super-Kamiokande and K2K. The survival probability for v[mu] is given approximately by 1 - sin22[theta]23sin2(1.27[Delta]m$2\atop{32}$L/E), where[theta]23 and [Delta]m$2\atop{32}$ are the mixing angle and difference in mass squared in eV2/c4 between the mass eigenstates v3 and v2, L is the distance traveled in km, and E is the neutrino energy in GeV. In the Near Detector at Fermilab, a measurement of the energy spectrum of the NuMI neutrino beam is made 1 km from the beam target. The neutrinos travel to the Far Detector in the Soudan Underground Laboratory, where another measurement of the energy spectrum is made 735 km from the target. MINOS measures.
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 Measuring nu mu Disappearance with the MINOS Experiment written by and published by . This book was released on 2011 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS Experiment consists of two steel-scintillator calorimeters, sampling the long baseline NuMI muon neutrino beam. It was designed to make a precise measurement of the 'atmospheric' neutrino mixing parameters, [Delta]m2 atm. and sin2 (2 atm.). The Near Detector measures the initial spectrum of the neutrino beam 1km from the production target, and the Far Detector, at a distance of 735 km, measures the impact of oscillations in the neutrino energy spectrum. Work performed to validate the quality of the data collected by the Near Detector is presented as part of this thesis. This thesis primarily details the results of a v[mu] disappearance analysis, and presents a new sophisticated fitting software framework, which employs a maximum likelihood method to extract the best fit oscillation parameters. The software is entirely decoupled from the extrapolation procedure between the detectors, and is capable of fitting multiple event samples (defined by the selections applied) in parallel, and any combination of energy dependent and independent sources of systematic error. Two techniques to improve the sensitivity of the oscillation measurement were also developed. The inclusion of information on the energy resolution of the neutrino events results in a significant improvement in the allowed region for the oscillation parameters. The degree to which sin2 (2[theta])= 1.0 could be disfavoured with the exposure of the current dataset if the true mixing angle was non-maximal, was also investigated, with an improved neutrino energy reconstruction for very low energy events. The best fit oscillation parameters, obtained by the fitting software and incorporating resolution information were.
Download or read book An Analysis of Muon Neutrino Disappearance from the NuMI Beam Using an Optimal Track Fitter written by and published by . This book was released on 2015 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NOvA experiment is a long-baseline neutrino oscillation experiment based out of Fermilab National Accelerator Laboratory that uses two liquid scintillator detectors, one at Fermilab (the \near" detector) and a second 14 kton detector in northern Minnesota (the \far" detector.) The primary physics goals of the NOvA experiment are to measure neutrino mixing parameters through both the v[mu] disappearance and ve appearance channels using neutrinos from the newly upgraded NuMI beam line. The NOvA v[mu] disappearance analysis can significantly improve the world's best measurement of sin2 [theta] 23. This analysis proceeds by using the measured v[mu] charged-current energy spectrum in the near detector to predict the spectrum in the far detector, and comparing this to the measured spectrum to obtain a best fit for the oscillation parameters sin2 [theta] 23 and [Delta]m2 32. Since this fit is governed by the shape of the energy spectrum, the best fit will be maximized by obtaining the best possible energy resolution for the individual neutrino events. This dissertation describes an alternate v[mu] disappearance analysis technique for the NOvA experiment, based on the idea that estimating the energy resolution of the individual events will allow them to be separated into different energy resolution samples in order to improve the final fit.
Download or read book Measurement of Muon Neutrino Disappearance with Non Fiducial Interactions 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: The NuMI (Neutrinos at the Main Injector) Off-Axis $\nu_e$ Appearance (NO$\nu$A) experiment is a long baseline neutrino oscillation experiment. The experiment measures the oscillations of a primarily muon neutrino beam using two functionally identical liquid scintillator tracking calorimeters detectors placed 810 km apart and 14 milliradians off-axis to the NuMI beam. The oscillation parameters $\sin^2 \theta_{23}$ and $\left.
Download or read book An Atmospheric Muon Neutrino Disappearance Measurement with the MINOS Far Detector written by Jeremy Peter Gogos and published by . This book was released on 2007 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Muon Neutrino Disappearance at MINOS written by and published by . This book was released on 2009 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: A strong case has been made by several experiments that neutrinos oscillate, although important questions remain as to the mechanisms and precise values of the parameters. In the standard picture, two parameters describe the nature of how the neutrinos oscillate: the mass-squared difference between states and the mixing angle. The purpose of this thesis is to use data from the MINOS experiment to precisely measure the parameters associated with oscillations first observed in studies of atmospheric neutrinos. MINOS utilizes two similar detectors to observe the oscillatory nature of neutrinos. The Near Detector, located 1 km from the source, observes the unoscillated energy spectrum while the Far Detector, located 735 km away, is positioned to see the oscillation signal. Using the data in the Near Detector, a prediction of the expected neutrino spectrum at the Far Detector assuming no oscillations is made. By comparing this prediction with the MINOS data, the atmospheric mixing parameters are measured to be [Delta]m322 = 2.45{sub +0.12}{sup -0.12} x 103 eV2 and sin2(2[theta]32) = 1.00{sub -0.04}{sup +0.00} (> 0.90 at 90% confidence level).
Download or read book Latest Results from the MINOS Experiment written by and published by . This book was released on 2010 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS experiment utilizes the NuMI neutrino beam to study the phenomenon of neutrino oscillations. Muon neutrinos are sent over a baseline of 735 km, with a detector near the production point at Fermilab and one at the Soudan underground laboratory in northern Minnesota. By observing the?{sub {mu}} disappearance characteristic of oscillations, MINOS can measure the oscillation parameters. MINOS has previously made the best measurement of the atmospheric-regime mass splitting to date. New results are presented in which the data-set is doubled. Further analysis improvements, and the inclusion of additional event samples, further improve the sensitivity to the oscillation parameters. The mixing angle?13 is currently not measured to differ from zero. By searching for?{sub e} appearance in the?{sub {mu}} beam, MINOS is able to set new limits on the value of?13. An observation of the neutral current interaction rate at the far detector allows limits to be placed on the existence of sterile neutrinos. From September 2009 to March 2010, MINOS has taken data with a dedicated {bar {nu}}{sub {mu}} beam, allowing the first direct precision measurement of the antineutrino oscillation parameters in the atmospheric regime.
Download or read book Sterile Neutrino Search with MINOS written by and published by . This book was released on 2015 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1km from the source of the beam and a far detector 734km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three avor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active avors as they propagate through space. This means that a muon type neutrino has a certain probability to later interact as a di erent type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino avors and two mass splittings, [Delta]m2. An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino avor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile avor may be observed by a de cit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile avor are driven by a large mass-squared di erence, m2s 1 eV2. The results of the 2013 sterile neutrino search are presented here.