Understanding the charged current quasielestic (CCQE) neutrino-nucleus interaction is important for precision studies of neutrino oscillations. The theoretical description of the interaction depends on the combination of a nuclear model with the knowledge of form factors. While the former has received considerable attention, the latter, in particular the axial form factor, is implemented using the historical dipole model. Instead, we use a model-independent approach, presented in a previous study, to analyze the muon antineutrino CCQE mineral oil data published by the MiniBooNE collaboration. We combine the cross section for scattering of antineutrinos off protons in carbon and hydrogen, using the same axial form factor for both. The extracted value of the axial mass parameter m A = 0.84 +0.12 −0.04 ± 0.11 GeV is in very good agreement with the modelindependent value extracted from MiniBooNE's neutrino data. Going beyond a oneparameter description of the axial form factor, we extract values of the axial form factor in the range of Q 2 = 0.1...1.0 GeV 2 , finding a very good agreement with the analogous extraction from the neutrino data. We discuss the implications of these results.

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We perform a combined analysis of inclusive electron scattering data from A = 3 nuclei in the deep-inelastic and quasielastic scattering regions, using Monte Carlo analysis methods and the nuclear weak binding approximation to establish the range over which the data can be described within the same theoretical framework. Comparison with quasielastic 3 He cross sections from SLAC and Jefferson Lab suggests that most features of the x 1 data can be reasonably well described in the impulse approximation with finite-Q 2 nuclear smearing functions for momentum transfers Q 2 1 GeV 2 . For the DIS region, we analyze the recent 3 He to deuterium cross section ratio from the Jefferson Lab E03-103 experiment to explore the possible isospin dependence of the nuclear effects. We discuss the implications of this for the MARATHON experiment at Jefferson Lab, and outline how a Bayesian analysis of 3 He, 3 H and deuterium data can robustly determine the free neutron structure function.

Transaural synthesis using loudspeaker signals determined through contemporaneous ear canal calibration is proposed as an alternative to headphone presentation for critical psychoacoustical experiments. The proposed technique can afford greater accuracy, improved reproducibility, and continuous signal monitoring. It allows the experimenter to compare listener responses to real and virtual presentations. In this article, the advantages of transaural (three or four loudspeakers) compared to crosstalk cancellation (two loudspeakers) are shown through computer modeling and manikin measurements in a moderately reverberant room. Measurements employ binaurally challenging signals and speech from a distant source. Transaural synthesis is shown to be a better solution to the essential inverse problem resulting in reduced average synthesis amplitudes, fewer large-amplitude outliers, improved amplitude and phase accuracy for real and imagined sources, and improved noise immunity. Immunity to inadvertent listener head rotation depends sensitively on loudspeaker placement and is not an advantage in general. Appendixes review the relevant mathematical foundation and extend it to the relationship between ear canal signals and eardrum signals.

The technique of crosstalk cancellation uses two synthesis loudspeakers in an attempt to produce well separated signals in a listener's ear canals. A variation on the technique can be applied in precise psychoacoustical experiments by using probe tubes in the ear canals throughout the presentation. The probe-tube application exhibits remarkable immunity to amplitude and phase variations in the responses of all transducers because the same system is used for presentation and for initial calibration. The self-correcting nature of the method even confers immunity to variations in the depth of the probe tubes within the ear canals. Because the solution to the 2-ear-2-speaker problem involves the inverse of a 2x2 matrix, the solution can become unstable, leading to pathologically large amplitudes. This problem can be almost entirely alleviated by using more than two synthesis speakers, and solving the resulting underdetermined inverse problem through the Moore-Penrose pseudoinverse. Random perturbation calculations show that using three or four synthesis speakers also reduces the ear-canal amplitude and phase sensitivity to inadvertent listener movements. However, more realistic calculations for inadvertent head-rotations indicate an additional important role for synthesis speaker location. [Work supported by the AFOSR.]

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