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Title: Physics with a very long neutrino factory baseline

Abstract

We discuss the neutrino oscillation physics of a very long neutrino factory baseline over a broad range of lengths (between 6000 km and 9000 km), centered on the 'magic baseline' ({approx}7500 km) where correlations with the leptonic CP phase are suppressed by matter effects. Since the magic baseline depends only on the density, we study the impact of matter density profile effects and density uncertainties over this range, and the impact of detector locations off the optimal baseline. We find that the optimal constant density describing the physics over this entire baseline range is about 5% higher than the average matter density. This implies that the magic baseline is significantly shorter than previously inferred. However, while a single detector optimization requires fine-tuning of the (very long) baseline length, its combination with a near detector at a shorter baseline is much less sensitive to the far detector location and to uncertainties in the matter density. In addition, we point out different applications of this baseline which go beyond its excellent correlation and degeneracy resolution potential. We demonstrate that such a long baseline assists in the improvement of the {theta}{sub 13} precision and in the resolution of the octant degeneracy. Moreover, wemore » show that the neutrino data from such a baseline could be used to extract the matter density along the profile up to 0.24% at 1{sigma} for large sin{sup 2}2{theta}{sub 13}, providing a useful discriminator between different geophysical models.« less

Authors:
 [1];  [2]
  1. Harish-Chandra Research Institute, Jhusi, Allahabad-211 019 (India)
  2. Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, D-97074 Wuerzburg (Germany)
Publication Date:
OSTI Identifier:
21020042
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.75.053002; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; CORRELATIONS; CP INVARIANCE; LENGTH; NEUTRINO DETECTION; NEUTRINO OSCILLATION; NEUTRINO REACTIONS; NEUTRINOS; OPTIMIZATION; POTENTIALS; RESOLUTION

Citation Formats

Gandhi, Raj, and Winter, Walter. Physics with a very long neutrino factory baseline. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.053002.
Gandhi, Raj, & Winter, Walter. Physics with a very long neutrino factory baseline. United States. doi:10.1103/PHYSREVD.75.053002.
Gandhi, Raj, and Winter, Walter. Thu . "Physics with a very long neutrino factory baseline". United States. doi:10.1103/PHYSREVD.75.053002.
@article{osti_21020042,
title = {Physics with a very long neutrino factory baseline},
author = {Gandhi, Raj and Winter, Walter},
abstractNote = {We discuss the neutrino oscillation physics of a very long neutrino factory baseline over a broad range of lengths (between 6000 km and 9000 km), centered on the 'magic baseline' ({approx}7500 km) where correlations with the leptonic CP phase are suppressed by matter effects. Since the magic baseline depends only on the density, we study the impact of matter density profile effects and density uncertainties over this range, and the impact of detector locations off the optimal baseline. We find that the optimal constant density describing the physics over this entire baseline range is about 5% higher than the average matter density. This implies that the magic baseline is significantly shorter than previously inferred. However, while a single detector optimization requires fine-tuning of the (very long) baseline length, its combination with a near detector at a shorter baseline is much less sensitive to the far detector location and to uncertainties in the matter density. In addition, we point out different applications of this baseline which go beyond its excellent correlation and degeneracy resolution potential. We demonstrate that such a long baseline assists in the improvement of the {theta}{sub 13} precision and in the resolution of the octant degeneracy. Moreover, we show that the neutrino data from such a baseline could be used to extract the matter density along the profile up to 0.24% at 1{sigma} for large sin{sup 2}2{theta}{sub 13}, providing a useful discriminator between different geophysical models.},
doi = {10.1103/PHYSREVD.75.053002},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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