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Killer whale discrete calls include types containing an overlapping high-frequency component (biphonic calls) and types without an overlapping high-frequency component (monophonic calls). In the resident killer whales of the Northeast Pacific, biphonic discrete calls exhibit higher source levels than monophonic calls, which suggests different active space(More)
Unlike most other mammals, killer whales are capable of vocal learning and learn the dialect of their natal pod from their mothers. The classical model of killer whale dialect development suggests that the repertoire of calls is learned only “vertically” from mother to offspring, and calls evolve gradually with time by random drift caused by the(More)
We investigated the influence of the type of activity and the social context on the proportion of four different structural categories of stereotyped calls in the acoustic communication of Kamchatkan killer whales. Using generalized linear models, we described the dependence of each sound category on the type of activity, the number of killer whale pods and(More)
The electronic desorption of CO and its readsorption on \aluminum (natural oxide film) was studied and found to be influenced by the adsorption of H2. A theoretical model was developed which fits the experimental data and reliably predicts the adsorption-desorption characteristics at low electron energies (100-300 eV). At higher energies the picture is(More)
The higher energies planned for the next generation of particle accelerators and storage rings makes the use of superconducting hi-Q RF cavities highly desirable. Past efforts to produce reliable cavities for such projects have met with limited success. Among the barriers to achieving the maximum electric field gradient are oxide layer charging, single(More)
A low-voltage test system is used to qualify various-III-V semiconductor materials as photocathodes for the SLC. The system features a load lock to introduce samples, high pumping speed, a sensitive residual gas-analyzer, and an infrared temperature detector. Heat cleaning, cesiation, and oxidation procedures have been studied to optimize cathode activation(More)
Measurements at 8.6 GHz on TM mode superconducting niobium cavities have been carried out at SLAC in an attempt to establish definitive conditions for reproducibly attaining high peak electric and magnetic fields and high residual &Is. Four cavities, processed by techniques which insure thepres-ence of an oxi& layer on the niobium surface before final high(More)