29 research outputs found
Vacuum-ultraviolet frequency-modulation spectroscopy
Frequency-modulation (FM) spectroscopy has been extended to the
vacuum-ultraviolet (VUV) range of the electromagnetic spectrum. Coherent VUV
laser radiation is produced by resonance-enhanced sum-frequency mixing
() in Kr and Xe using two
near-Fourier-transform-limited laser pulses of frequencies
and . Sidebands generated in the output of the second laser ()
using an electro-optical modulator operating at the frequency
are directly transfered to the VUV and used to record FM
spectra. Demodulation is demonstrated both at and
. The main advantages of the method are that its
sensitivity is not reduced by pulse-to-pulse fluctuations of the VUV laser
intensity, compared to VUV absorption spectroscopy is its background-free
nature, the fact that its implementation using table-top laser equipment is
straightforward and that it can be used to record VUV absorption spectra of
cold samples in skimmed supersonic beams simultaneously with
laser-induced-fluorescence and photoionization spectra. To illustrate these
advantages we present VUV FM spectra of Ar, Kr, and N in selected regions
between 105000cm and 122000cm.Comment: 23 pages, 10 figure
Harmonizing methods for wildlife abundance estimation and pathogen detection in Europe-a questionnaire survey on three selected host-pathogen combinations
__Background:__ The need for wildlife health surveillance as part of disease control in wildlife, domestic animals and humans on the global level is widely recognized. However, the objectives, methods and intensity of existing wildlife health surveillance programs vary greatly among European countries, resulting in a patchwork of data that are difficult to merge and compare. This survey aimed at evaluating the need and potential for data harmonization in wildlife health in Europe. The specific objective was to collect information on methods currently used to estimate host abundance and pathogen prevalence. Questionnaires were designed t
Geologia della Conca di Arabba
Guide Geologiche Regionali, Società Geologica Italian