835 research outputs found

    Introduction

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    What are the strategies, modalities and aspirations of island-based, stateless nationalist and regionalist parties in the twenty-first century? Political independence is now easier to achieve, even by the smallest of territories; yet, it is not so likely to be pursued with any vigour by the world's various persisting sub-national (and mainly island) jurisdictions. Theirs is a pursuit of different expressions of sub-national autonomy, stopping short of independence. And yet, a number of independence referenda are scheduled, including one looming in Scotland in autumn 2014

    Stratigraphy of the East Flank of the Green Mountain Anticlinorium, Southern Vermont

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    Guidebook for field trips in Vermont: 64th annual meeting October 13, 14, 15, 1972 Burlington, Vermont: Trip B-

    Narrowband spectroscopy by all-optical correlation of broadband pulses

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    High peak power ultrafast lasers are widely used in nonlinear spectroscopy but often limit its spectral resolution because of the broad frequency bandwidth of ultrashort laser pulses. Improving the resolution by achieving spectrally narrow excitation of, or emission from, the resonant medium by means of multi-photon interferences has been the focus of many recent developments in ultrafast spectroscopy. We demonstrate an alternative approach, in which high resolution is exercised by detecting narrow spectral correlations between broadband excitation and emission optical fields. All-optical correlation analysis, easily incorporated into the traditional spectroscopic setup, enables direct, robust and simultaneous detection of multiple narrow resonances with a single femtosecond pulse.Comment: 5 pages, 4 figures, submitted to PR

    Pulsed-field ionization threshold photoelectron spectroscopy with coherent extreme ultraviolet radiation: A comparison of CO and N_2

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    Single‐photon zero‐kinetic‐energy pulsed‐field‐ionization spectra have been measured for the v^+=0 and 1 levels of CO^+ (X  ^2ÎŁ^+) and the v^+=0 level of N_2^+ (X  ^2ÎŁ_g^+) by coherent XUV radiation. In spite of similarities in the electronic structure of CO and N_2, the measured ion spectra show dramatically different intensities for the Q branches. These threshold spectra are interpreted on the basis of ab initio calculations of the ion rotational distributions. Agreement between the calculated and measured spectra is very encouraging. Improved values for the ionization potentials of CO (113 025.6 and 115 211.2±1.5 cm^(−1) for v^+=0 and 1, respectively) are reported and the unusual dynamics favoring ΔN<0 transitions are discussed. The CO spectra show quite different behavior for the ΔN<0 transitions for v^+=0 and v^+=1 bands, which is interpreted in terms of the relative importance of rotational autoionization in the two bands
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