Bau der thermische Infrarotkamera, TIMMI 2, fuer den Wellenlaengenbereich 10-20 Mikrometer Schlussbericht

Available from TIB Hannover: DtF QN1(60,21) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Entwicklungsmaessige Fruehstadien von Sternen im unteren Massebereich Schlussbericht

SIGLEAvailable from TIB Hannover: DtF QN1(63,28) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

CODAG (1. Projektphase) Abschlussbericht

Available from TIB Hannover: F97B2188+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany); Deutsche Agentur fuer Raumfahrtangelegenheiten (DARA) GmbH, Bonn (Germany)DEGerman

CODAG. 2. Phase Abschlussbericht

SIGLEAvailable from TIB Hannover: DtF QN1(85,20) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

ISO-Beobachtungen der zirkumstellaren Materie von sehr jungen und massereichen Sternen Schlussbericht

Available from TIB Hannover: DtF QN1(86,45) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Untersuchung der Staubeigenschaften von Wolken in zirkumstellaren Gas-Staub-Huellen um junge Sterne Abschlussbericht

Available from TIB Hannover: DtF QN1(54,10) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDeutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman

Detection of planetary spectral features through circumstellar dust - a Monte Carlo simulation

One of the methods envisaged to detect planets outside of our solar system assumes that certain spectroscopic features at 10 and below 20 #mu#m wavelength are typical of planets. Their detection would then be an unambiguous sign of the presence of Earth-like planets other than ours. In these spectral regions, there might be interference with other features being generally typical of circumstellar material: the silicate features of dust. In order to get an estimate of this effect, we used our 3D Monte Carlo radiation transport code to model the spectrum of a Keplerian disk with embedded artificial planets encircling a central star of solar luminosity and temperature. The disk structure and the grain model resemble real properties in protoplanetary disks. The model was calculated for a set of different optical depths at various positions of the observer in respect to the configuration, the detectability of the embedded planetary sources is discussed. (orig.)SIGLEAvailable from TIB Hannover: RR 8257(59) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

The outburst of the T Tauri star EX Lupi in 1994

We have observed an outburst of the T Tauri star EX Lup in March 1994. We present both photometric (BVR) and spectroscopic (low and medium resolution) observations carried out during the decline after outburst. The star appears much bluer during outburst due to an increased emission of a hot continuum. This is accompanied by a strong increase of the veiling of photospheric lines. We observe inverse P Cygni profiles of many emission lines over a large brightness range of EX Lup. We briefly discuss these features towards the model of magnetospherically supported accretion of disk material. (orig.)SIGLEAvailable from TIB Hannover: RR 8257(43) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany); Deutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman

Aluminum oxide and the opacity of oxygen-rich circumstellar dust in the 12-17-#mu#m range

Amorphous alumina (Al_2O_3) was produced by a sol-gel technique in order to make available its optical constants for possible astrophysical applications. Gradual annealing showed that the X-ray amorphousness of alumina ended somewhere between 723 and 873 K. Above this transition point, the structure changes into disordered #gamma#-Al_2O_3. At T>1273 K crystalline #alpha#-Al_2O_3 (corundum) is formed. Mie calculations show that amorphous alumina exhibits a wide Al-O vibrational band, peaking at 11.5-11.8 #mu#m and having a steep 'blue' and an extended 'red' wing. It may be an important contributor to the continuous opacity between the silicate bands in oxygen-rich circumstellar envelopes, whereas it is ruled out for the explanation of the 13-#mu#m band. An average 13-#mu#m band profile was derived from 51 IRAS LRS spectra of bright Mira stars and semiregular variables. Its shape, which is satifactorily represented by a Lorentz profile, can be reproduced by Mie calculations with the data of #alpha#-Al_2O_3, but not with those of #gamma#-Al_2O_3. The calculations show that the 13-#mu#m band profile of #alpha#-Al_2O_3 is sensitive to grain shape. If #alpha#-Al_2O_3 is the absorber, a second band should be present at 21 #mu#m. A close correlation was found between the strengths of the 13-#mu#m band and the 10-#mu#m silicate band. It suggests that the 13-#mu#m band carrier could also be somehow connected with silicate dust. Experimental arguments supporting this attribution are presented. (orig.)SIGLEAvailable from TIB Hannover: RR 8257(63) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

MANIAC - a new mid- and near-infrared camera

We present the optical, mechanical and electronical design of MANIAC, the Mid- And Near-Infrared Array Camera, together with some results from the first observing run. MANIAC is a two-channel instrument that offers observations from 1 to 5 #mu#m and from 8 to 28 #mu#m at the same time. The advantages of the purely reflective optical design of MANIAC are discussed as well as the options that are provided by simultaneous observations in the two regimes. The construction of MANIAC will be completed in a modular way, each of the five phases offering a fully operational instrument. The first phase, a mid-infrared camera based on a Rockwell 128 x 128 pixel Si:As detector, has now been completed. With a pixel scale of about 0.2 arcsec, the MANIAC mid-infrared channel offers diffraction-limited imaging in the N and Q bands at a 4m-class telescope and a field of view of 26 x 26 arcsec. The sensitivity achieved in N-band is very close to the background limit under all observational modes. We also discuss the scientific importance of high-resolution mid-infrared observations, describe the observing methods and characterize the performance of the detector array. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman