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Study On Non Standard Interaction Of Neutrino And Unparticle Physics With Neutrino-electron Scattering Data At Low Energy In Texono ExperimentBilmis, Selcuk 01 October 2010 (has links) (PDF)
Neutrino-electron scatterings are purely leptonic processes with robust Standard Model (SM)
predictions. Their measurements can therefore provide constraints to physics beyond SM.
The &nu / e &minus / e&minus / data taken at the Kuo-Sheng Reactor Neutrino Laboratory were used to probe two sceneria: Non-Standard Neutrino Interactions (NSI) and Unparticle Physics. New constraints
were placed to the NSI parameters (&epsilon / eL , &epsilon / eR ), (&epsilon / eL , &epsilon / eR ) and (&epsilon / eL , &epsilon / eR ) , as well as to the coupling constants for scalar (&lambda / 0 ) and vector (&lambda / 1 ) unparticles to the neutrinos and electrons.
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High-speed Automatic Scanning System For Emulsion Analysis In The Opera ExperimentAltinok, Ozgur 01 July 2011 (has links) (PDF)
The aim of the OPERA experiment is to verify the neutrino oscillation, directly measuring
the appearance of from an initially pure beam produced at CERN. For this purpose
OPERA detector is located underground Gran Sasso Laboratory(LNGS) 730 km away from
CERN. The detector structure designed to be a hybrid system consisting of emulsion targets
and electronic detectors. Total area of the emulsion targets in the OPERA detector is around
110000 m2 which needs fast and reliable automatic scanning systems. For this purpose, two
dierent automatic scanning systems were developed in Japan and Europe. For now there
are 12 scanning laboratories dedicated to the OPERA Experiment. The Emulsion Scanning
Laboratory in the Physics department of METU is one of the scanning laboratories for the
OPERA Experiment. The automatic scanning system in METU is European type which is
using commercial hardware for easy construction and maintain. Also the laboratory has a
unique feature in terms of experimental high energy physics laboratories. The emulsion scan-
ning laboratory in METU is the
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Development of a particle flux detection system for the MERIT high intensity target experiment at CERNPalm, Marcus January 2008 (has links)
<p>The construction of a high intensity neutrino source requires multi megawatt beams and challenges the targets in use. MERIT is a proof-of-principle test for a novel kind of neutrino factory target, employing a 24 GeV/c proton beam and a 1 cm in diameter free mercury jet as beam target. This thesis describes the design and implementation of a secondary particle flux production detection system. Employed detectors are polycrystalline diamond detectors and electron multipliers. Simulations of the secondary particle production have been made using FLUKA. The detection system is remotely controlled by a LabView interface and experimental observations from the initial analysis are presented.</p>
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Toward an understanding of the large scale structure of the universe with galaxy surveysShoji, Masatoshi 01 February 2012 (has links)
Large-scale structures we see in the universe, such as galaxies,
galaxy clusters and structures beyond the scale of clusters, result from
gravitational instability of
almost isotropic and homogeneous density distribution
in the early universe. The degree of the initial anisotropy of the universe
and the subsequent growth of gravitational instability, coupled
with the expansion rate of the universe, determine the scale and abundance
of the structures formed in the universe at later times.
A galaxy survey directly observes a distribution of structures in
the sky using galaxies as a tracer of the underlying density distribution,
and yields constraints on cosmological models when compared to a
physical theory of structure formation based on a given cosmological model.
Among many cosmological and astronomical phenomena to be understood
from a galaxy survey, the nature of the observed accelerated expansion
of the universe is the most profound problem in the modern physics.
Motivated by various planned and on-going galaxy surveys,
including our own Hobby-Ebery Telescope Dark Energy eXperiment (HETDEX),
we show the way to fully exploit the data from a galaxy survey.
We improve a model of structure formation to include the effect
of baryonic pressure and the free-streaming of massive neutrinos at a mildly non-linear regime.
Future galaxy surveys are to reach the level of accuracy, where
the effect of massive neutrinos on the observed power spectrum is no longer negligible.
Proper understanding of these effects gives a way to measure
the absolute masses of neutrinos: one of the most fundamental particles,
which, by itself, will be a major development in the field of particle
physics.
Yet, most of the space (~80%) observed by galaxy surveys is
occupied by voids.
An ellipticity probability distribution function of voids
offers yet another way of probing cosmology.
Especially, a distribution of ellipticities in the redshift space
provides a unique way to measure a growth rate of the
structure in the universe apart from other cosmological parameters
when combined with the galaxy power spectrum. / text
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Dark Matter in the Galactic Halo : A Search Using Neutrino Induced Cascades in the DeepCore Extension of IceCubeTaavola, Henric January 2015 (has links)
A search for Weakly Interacting Massive Particles (WIMPs) annihilating in the dark matter halo of the Milky Way was performed, using data from the IceCube Neutrino Observatory and its low-energy extension DeepCore. The data were collected during one year between 2011 to 2012 corresponding to 329.1 days of detector livetime. If WIMPs in the dark matter halo undergo pairwise annihilation they may produce a neutrino signal detectable at the Earth. Assuming annihilation into bb, W+W-, τ+τ-, μ+μ-, νν and a neutrino flavor ratio of 1:1:1 at the detector, cascade events from all neutrino flavors were used to search for an excess of neutrinos matching a dark matter signal spectrum. Two dark matter density profiles for the halo were used; the cored Burkert profile and the cusped NFW profile. No excess of neutrinos from the Galactic halo was observed, and upper limits were set for the thermally averaged product of the WIMP self-annihilation cross section and velocity, <σAv>, in the WIMP mass range 30 GeV to 10 TeV. For the bb annihilation channel and the NFW halo profile, the 90% C.L. upper limits are 9.03×10-22 cm3 s-1 for the mass WIMP 100 GeV and 4.08×10-22 cm3 s-1 for the WIMP mass 3000 GeV. The corresponding upper limits for the μ+μ- annihilation channel are 4.40×10-23 cm3 s-1 and 3.20×10-23 cm3 s-1. / IceCube
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Non-Equilibrium Aspects of Relic Neutrinos: From Freeze-out to the Present DayBirrell, Jeremiah January 2014 (has links)
In this dissertation, we study the evolution and properties of the relic (or cosmic) neutrino distribution from neutrino freeze-out at T=O(1) MeV through the free-streaming era up to today, focusing on the deviation of the neutrino spectrum from equilibrium and in particular we demonstrate the presence of chemical non-equilibrium that continues to the present day. The work naturally separates into two parts. The first focuses on aspects of the relic neutrinos that can be explored using conservation laws. The second part studies the neutrino distribution using the full general relativistic Boltzmann equation. Part one begins with an overview of the history of the Universe, from just prior to neutrino freeze-out up through the present day, placing the history of cosmic neutrino evolution in its proper context. Motivated by the Planck CMB measurements of the effective number of neutrinos, we derive those properties of neutrino freeze-out that depend only on conservation laws and are independent of the details of the scattering processes. Part one ends with a characterization of the present day neutrino spectrum as seen from Earth. The second part of this dissertation focuses on the properties of cosmic neutrinos that depend on the details of the neutrino reactions, as is necessary for modeling the non-thermal distortions from equilibrium and computing freeze-out temperatures. We first develop some geometry background concerning volume forms and integration on submanifolds that is helpful in computations. We then detail a new spectral method for solving the Boltzmann equation, based on a dynamical basis of orthogonal polynomials. Next, we detail an improved procedure for analytically simplifying the corresponding scattering integrals for subsequent numerical computation. Using this, along with the spectral method mentioned above, we solve the Boltzmann equation through the neutrino freeze-out period. Finally, we conclude by using our novel solution methods to perform parametric studies of the dependence of the neutrino freeze-out standard model parameters. This exploration is performed with the aim of recognizing mechanisms in the neutrino freeze-out process that are capable of leading to the measured value of the effective number of neutrinos.
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Lives of White Dwarf StarsRicher, Harvey 17 March 2008 (has links)
White dwarf stars are the burnt out remnants that remain after a
star like the Sun has completed its nuclear evolution. In such a
star there are no remaining nuclear energy sources, so the star
evolves by simply radiating its stored thermal energy out into
space. This may seem rather uninteresting, but in fact there is a
wealth of physical phenomena that occur during this part of a
star's life - from getting kicked at birth, to neutrino emission
in early life, to some interesting high density physics, through
to functioning as precise clocks that can provide an age for some
of the oldest know stars in the Universe. Some of these phases
will be illustrated with detailed observations taken recently with
the Hubble Space Telescope.
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Beta beams and ion cooling : Future of accelerator driven neutrino oscillations?Rubbia, Carlo 06 May 2008 (has links)
No description available.
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Time distribution analysis for flasher data and simulations in the IceCube neutrino detectorSarah, Bouckoms January 2011 (has links)
The IceCube neutrino observatory is located in the deep glacial ice below the South Pole. IceCube
consists of over 5, 000 photomultiplier tubes regularly spaced throughout a cubic kilometre volume
of ice. The photomultiplier tubes are receptive to the light produced by high energy neutrino
interactions. As a means of evaluating our understanding of the physics of light propagation, a
comparison was made between the data taken from artificial light sources and Monte Carlo
simulations of these events. The evaluation was done by comparing the shape of the light
arrival-time distributions. The three icemodels compared were the Additionally Heterogeneous
Absorption (AHA), South Pole Ice - 1 (Spice) and South Pole Ice - Mie (Spice Mie). The artificial
light sources used are LEDs, known as flashers, located within each of the detector modules. The
data set used in this study was taken on string 63 with single- photoelectron settings (one LED).
Various orientations of the flashing LED and relative position of the light source in the detector,
were studied over 15 depths in instrumented ice. Through a χ2 comparison and distribution
characteristics it was found that for the majority of cases, simulations which used the
Spice Mie ice model matched the data best. There were, however, some isolated cases in which
simulations using the Spice 1 or AHA ice models matched the flasher data best.
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Evaluating the performance of a prototype TPC for use in the ND280m detector of the T2K experimentFransham, Kyle Bleadon 21 November 2007 (has links)
A prototype time projection chamber has been designed and constructed to study the performance that can be expected by the large scale time projection chambers in the ND280m detector of the Tokai to Kamioka (T2K) neutrino oscillation experiment.
Tests using the prototype will indicate any changes necessary to the fullscale design in order to meet the physics goals of the detectors.
Some TPC gas parameters are measured, including the drift velocity, diffusion constant, and electron attachment coefficient. The spatial resolution of the TPC is also measured, and results are presented for two candidate TPC gasses.
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