We report a measurement of the atmospheric neutrino flavor ratio, R, using a sample of quasi-elastic neutrino interactions occurring in an iron medium. The flavor ratio (tracks/showers) of ...atmospheric neutrinos in a 3.9 fiducial kiloton-year exposure of Soudan 2 is 0.64±0.11(stat.)±0.06(syst.) of that expected. Important aspects of our main analysis have been checked by carrying out two independent, alternative analyses; one is based upon automated scanning, the other uses a multivariate approach for background subtraction. Similar results are found by all three approaches.
A shadow of the Moon, with a statistical significance of 5{sigma}, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the ...detector is well described by a Gaussian with a sigma {<=}0.3 degree sign . The position of the shadow confirms that the alignment of the detector is known to better than 0.15 degree sign and has remained stable during ten years of data taking. (c) 2000 The American Physical Society.
We measure the horizontal (|cos(
θ
z
)|<0.14 corresponding to a slant depth cut 14 kmwe) neutrino-induced muon flux (
E
μ>1.8 GeV) in Soudan 2 to be 4.01
±
0.50
±
0.30
×
10
−13 cm
−2
sr
−1
s
−1. From ...the absence of horizontal muons with large energy loss, we set a limit on the flux of muon neutrinos from active galactic nuclei.
Uncertainties in the NLO calculation of the inclusive jet cross section due to the choice of renormalization scale, parton distribution functions and clustering algorithm are explored. These are ...found to be similar in size to the current experimental uncertainties of the measured inclusive jet cross section at DØ and CDF.
We have searched for the proton decay mode p {yields} {nu} K{sup +} using the one-kiloton Soudan 2 high resolution calorimeter. Contained events obtained from a 3.56 kiloton-year fiducial exposure ...through June 1997 are examined for occurrence of a visible K{sup +} track which decays at rest into {mu}{sup +}{nu} or {pi}{sup +}{pi}{sup 0}. We found one candidate event consistent with background, yielding a limit, {tau}/B(p {yields} {nu} K{sup +})>4.3x10{sup 31} years at 90% CL with no background subtraction.