An Infrared Camera for Leuschner Observatory and the Berkeley Undergraduate Astronomy Lab

We describe the design, fabrication, and operation of an infrared camera which is in use at the 30-inch telescope of the Leuschner Observatory. The camera is based on a Rockwell PICNIC 256 x 256 pixel HgCdTe array, which is sensitive from 0.9-2.5 micron. The primary purpose of this telescope is for undergraduate instruction. The cost of the camera has been minimized by using commercial parts whereever practical. The camera optics are based on a modified Offner relay which forms a cold pupil where stray thermal radiation from the telescope is baffled. A cold, six-position filter wheel is driven by a cryogenic stepper motor, thus avoiding any mechanical feed throughs. The array control and readout electronics are based on standard PC cards; the only custom component is a simple interface card which buffers the clocks and amplifies the analog signals from the array.Comment: 13 pages, 17 figures. Submitted to Publications of the Astronomical Society of the Pacific: 2001 Jan 10, Accepted 2001 Jan 1

Використання автентичних друкованих текстів як засіб формування лексичної компетенції на початковому етапі навчання іноземної мови у студентів мовних вузів

Het rekenen in het basisonderwijs is al geruime tijd het onderwerp van discussie. In onderstaand artikel betogen Marja van den Heuvel-Panhuizen en Adri Treffers van het Freudenthal Instituut, dat als er geen methodevernieuwing had plaatsgevonden, de uitkomsten van het rekenwiskundeonderwijs thans lager zouden zijn geweest. Ze baseren zich op periodieke peilingen van het onderwijsniveau, uitgevoerd door het Cito

The Lick Observatory Supernova Search

We report here the current status of the Lick Observatory Supernova Search (LOSS) with the Katman Automatic Imaging Telescope (KAIT). The progress on both the hardware and the software of the system is described, and we present a list of recent discoveries. LOSS is the world' most successful search engine for nearby supernovae.Comment: 4 pages, 1 figure, Submitted to the proceedings of the 10th Annual October Astrophysics Conference in Maryland on Cosmic Explosion

SN 1997bs in M66: Another Extragalactic Eta Carinae Analog?

We report on SN 1997bs in NGC 3627 (M66), the first supernova discovered by the Lick Observatory Supernova Search using the 0.75-m Katzman Automatic Imaging Telescope (KAIT). Based on its early-time optical spectrum, SN 1997bs was classified as Type IIn. However, from the BVRI light curves obtained by KAIT early in the supernova's evolution, and F555W and F814W light curves obtained from Hubble Space Telescope archival WFPC2 images at late times, we question the identification of SN 1997bs as a bona fide supernova. We believe that it is more likely a super-outburst of a very massive luminous blue variable star, analogous to Eta Carinae, and similar to SN 1961V in NGC 1058 (Filippenko et al. 1995 [AJ, 110, 2261]) and SN 1954J (``Variable 12'') in NGC 2403 (Humphreys & Davidson 1994 [PASP, 106, 1025]). The progenitor may have survived the outburst, since the SN is seen in early 1998 at m_F555W=23.4, about 0.5 mag fainter than the progenitor identified by Van Dyk et al. (1999, [AJ, 118, 2331]) in a pre-discovery image. Based on analysis of its environment in the Hubble Space Telescope images, the progenitor was not in an H II region or association of massive stars. The recent discovery of additional objects with properties similar to those of SN 1997bs suggests that the heterogeneous class of Type IIn supernovae consists in part of ``impostors.''Comment: 15 pages, 8 figures, to appear in the PASP (2000 Dec issue

Panoramic optical and near-infrared SETI instrument: prototype design and testing

The Pulsed All-sky Near-infrared Optical Search for ExtraTerrestrial Intelligence (PANOSETI) is an instrument program that aims to search for fast transient signals (nano-second to seconds) of artificial or astrophysical origin. The PANOSETI instrument objective is to sample the entire observable sky during all observable time at optical and near-infrared wavelengths over 300 - 1650 nm$^1$. The PANOSETI instrument is designed with a number of modular telescope units using Fresnel lenses ($\sim$0.5m) arranged on two geodesic domes in order to maximize sky coverage$^2$. We present the prototype design and tests of these modular Fresnel telescope units. This consists of the design of mechanical components such as the lens mounting and module frame. One of the most important goals of the modules is to maintain the characteristics of the Fresnel lens under a variety of operating conditions. We discuss how we account for a range of operating temperatures, humidity, and module orientations in our design in order to minimize undesirable changes to our focal length or angular resolution.Comment: 12 pages, 8 figures, 1 tabl

L1 transfer in the acquisition of manner and path in Spanish by native speakers of English

In this article the authors argue that L1 transfer from English is not only important in the early stages of L2 acquisition of Spanish, but remains influential in later stages if there is not enough positive evidence for the learners to progress in their development (Lefebvre, White, & Jourdan, 2006). The findings are based on analyses of path and manner of movement in stories told by British students of Spanish (N = 68) of three different proficiency levels. Verbs that conflate motion and path, on the one hand, are mastered early, possibly because the existence of Latinate path verbs, such as enter and ascend in English, facilitate their early acquisition by British learners of Spanish. Contrary to the findings of Cadierno (2004) and Cadierno and Ruiz (2006), the encoding of manner, in particular in boundary crossing contexts, seems to pose enormous difficulties, even among students who had been abroad on a placement in a Spanish-speaking country prior to the data collection. An analysis of the frequency of manner verbs in Spanish corpora shows that one of the key reasons why students struggle with manner is that manner verbs are so infrequent in Spanish. The authors claim that scarce positive evidence in the language exposed to and little or no negative evidence are responsible for the long-lasting effect of transfer on the expression of manner

An X-ray and Optical Investigation of the Starburst-driven Superwind in the Galaxy Merger Arp 299

We present a detailed investigation of the X-ray and optical properties of the starburst-merger system Arp299 (NGC 3690, Mrk 171), with an emphasis on its spectacular gaseous nebula. We analyse \rosat and \asca X-ray data and optical spectra and narrow-band images. We suggest that the on-going galaxy collision has tidally-redistributed the ISM of the merging galaxies. The optical emission-line nebula results as this gas is photoionized by radiation that escapes from the starburst, and is shock-heated, accelerated, and pressurized by a `superwind' driven by the collective effect of the starburst supernovae and stellar winds. The X-ray nebula in Arp 299 is is plausibly a mass-loaded flow of adiabatically-cooling gas that carries out a substantial fraction of the energy and metals injected by the starburst at close to the escape velocity from Arp 299. The mass outflow rate likely exceeds the star-formation rate in this system. We conclude that powerful starbursts are able to heat (and possibly eject) a significant fraction of the ISM in merging galaxies.Comment: 54 pages, 17 postscript figures, AAS late

Assumptions behind grammatical approaches to code-switching: when the blueprint is a red herring

Many of the so-called ‘grammars’ of code-switching are based on various underlying assumptions, e.g. that informal speech can be adequately or appropriately described in terms of ‘‘grammar’’; that deep, rather than surface, structures are involved in code-switching; that one ‘language’ is the ‘base’ or ‘matrix’; and that constraints derived from existing data are universal and predictive. We question these assumptions on several grounds. First, ‘grammar’ is arguably distinct from the processes driving speech production. Second, the role of grammar is mediated by the variable, poly-idiolectal repertoires of bilingual speakers. Third, in many instances of CS the notion of a ‘base’ system is either irrelevant, or fails to explain the facts. Fourth, sociolinguistic factors frequently override ‘grammatical’ factors, as evidence from the same language pairs in different settings has shown. No principles proposed to date account for all the facts, and it seems unlikely that ‘grammar’, as conventionally conceived, can provide definitive answers. We conclude that rather than seeking universal, predictive grammatical rules, research on CS should focus on the variability of bilingual grammars