Variation of fluxes of RR Tel emission lines measured in 2000 with respect to 1996

The aim of this work is to make available unpublished non-Fe+ emission line fluxes from optical spectra of the symbiotic nova RR Tel which were taken in 2000, and to compare them with fluxes of the same lines from spectra taken in 1996. After leaving out blends and misidentifications, as well as the unreliable far-red and violet lines, we present the log (F2000/F1996) flux ratios for identified non-Fe+ lines. Mean values of log (F2000/F1996) for different ionization potential ranges of the ions producing the lines are shown separately for the permitted and forbidden lines. All means show fading, which is larger in the lowest range of ionization potential. Provisional interpretations are suggested. We also measured the values of FWHM in 2000; the previously known decrease with time of FWHM of lines due to the same ion has continued.Comment: 16 pages, 5 figure

The Role of Spatial Coherence and Orbital Angular Momentum of Light in Astronomy

The orbital angular momentum (OAM) of light is potentially interesting for astronomical study of rotating objects such as black holes, but the effect of reduced spatial coherence of astronomical light sources such as stars is largely unknown. In a lab-scale experiment, we find that the detected OAM spectrum depends strongly on the position of the light-twisting object along the line of sight. We develop a simple intuitive model to predict the influence of reduced spatial coherence in astronomical observations, and discuss line-of-sight and intensity issues.Comment: updated versio

'Realis' and 'irrealis' in Wogeo: A valid category?

Finite verb forms in Wogeo, an Austronesian language of New Guinea, are obligatorily marked with a portmanteau prefix denoting person and number of the subject on the one hand, and a grammatical category that is conventionally glossed in the literature as realis–irrealis, on the other. In similar languages, the latter category is usually described as modal, with a certain range of meanings which is, in many cases, only vaguely defined. A more in-depth investigation of the verbal system of Wogeo and the functional distribution of the respective categories shows, however, that the language is quite different from a postulated prototypical realis–irrealis language. Central attributes of the supposed realis–irrealis semantics are not realized by the obligatory prefixes but by other morphosyntactic means, while the prefixes are restricted to only a small part of the assumed realis–irrealis domain.National Foreign Language Resource Cente

Properties of the Anterior and Posterior Click Closures in N|uu

In this dissertation, the phonetic and phonological system of N|uu is described and analyzed. The dissertation is based on original fieldwork by the author. As is shown at the outset in Chapter 2, N|uu is a Tuu (formerly 'Southern Khoisan') language of the Kalahari region of South Africa. It is a severely endangered language on the verge of extinction, spoken at the time of writing by less than ten elderly speakers. At the same time, it is a phonetically and phonologically highly complex language, most notably including a large number of phonologically contrastive click consonants. In Chapter 3, an overview of the entire phoneme inventory is presented for the first time, including not only the click subsystem (here, the terms simultaneous release vs. sequential release are introduced), but also the non-click consonants and vowels, as well as the as yet unanalyzed lexical tone system. Then, in Chapter 4, the phonological structure of N|uu is analyzed qualitatively and quantitatively, and the foot is for the first time identified as a fundamental organizing unit in the prosodic system of the language. Also, the complexity of phonological words in N|uu is shown to be considerably greater than previously thought. Chapter 5 presents two detailed experimental case studies (one on the anterior click closure, one on the posterior click closure) that help to shed some light on our understanding of the underlying representation of clicks. In the first of these studies, the so-called Back Vowel Constraint (BVC; a constraint that states that certain click types only occur before back vowels, while other click types co-occur freely with all vowels) in N|uu is analyzed in terms of differences in tongue shape in the different categories of clicks. In the second study, stiffness is identified as an articulatory parameter in N|uu. Finally, in Chapter 6, a synthesis of the new insights gained in the previous chapters is attempted in the form of a novel scheme for categorizing and transcribing clicks. In this context, the categorical terms deep concave vs. shallow concave are introduced for the systematic tongue shape differences in clicks, and the terms tense vs. lax are proposed to capture the categorical effect of articulatory stiffness in clicks