Matter Density versus Distance for the Neutrino Beam from Fermilab to Lead, South Dakota, and Comparison of Oscillations with a Variable and a Constant Density

TL;DR

This study calculates Earth's crustal densities along a neutrino path from Fermilab to Sanford Laboratory using recent and older models, then compares neutrino oscillation results for variable and constant density assumptions.

Contribution

It provides a detailed comparison of Earth's crustal density models and their impact on neutrino oscillation predictions at Sanford Laboratory.

Findings

Density variations have minimal impact on oscillation results.

Recent density models offer refined estimates for neutrino path analysis.

Constant density approximation is adequate for current oscillation predictions.

Abstract

This paper is divided into two parts. In the first part, the material densities passed through for neutrinos going from FNAL to Sanford Laboratory are calculated using two recent density tables, Crustal [G. Laske, G. Masters. Z. Ma, and M. Pasyanos, Update on CRUST1.0 -- A 1-degree global model of Earth's crust, Geophys. Res. Abstracts 15, EGU2013-2658 (2013)] and Shen-Ritzwoller [W. Shen and M. H. Ritzwoller. Crustal and uppermost mantle structure beneath the United States, J. Geophys. Res.: Solid Earth 121, 4306 (2016)], as well as the values from an older table PEMC [A. M. Dziewonski, A. L. Hales and E. R. Lapwood, Parametrically simple earth models consistent with geophysical data, Phys. Earth Plan. Int. 10 12 (1975)]. In the second part, neutrino oscillations at Sanford Laboratory are examined for the variable density table of Shen-Ritzwoller. These results are then compared with oscillation results using the mean density from the Shen-Ritzwoller tables and one other fixed density. For the tests made here, the mean density results are quite similar to those found using the variable density vs distance.