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New X-ray sources detected among mild barium and S stars.
Schmitt, J. H. M. M.; Jorissen, A.; Ginestet, N. +2 more
We report on the detection by ROSAT of X-rays from the mild barium star HD 165141 (K0III/IIBa1) and from the S stars HD 35155 (S4,1) and HR 363 (S3/2). For the S stars, the X-ray flux is attributed to the accretion of the red-giant wind by the white dwarf companion. The strong variability observed in the X- and UV fluxes on time scales of both hou…
LWS observations of the colliding galaxies NGC 4038/39.
Malkan, M. A.; Ade, P. A. R.; Miles, J. W. +31 more
Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) and ground-based Fabry-Perot imaging spectroscopic observations are used to penetrate the extinction to the powerful burst of star formation that has occurred in the extranuclear molecular cloud complex in the galaxy overlap region of the galaxies NGC 4038/39 ("The Antennae"). Par…
NGC 5195 - a look into the hot dusty ISM of an interacting SB0 galaxy with ISOCAM.
Altieri, B.; Okumura, K.; Sauvage, M. +8 more
We present broad-band images and a CVF spectrum of NGC 5195, the companion of M51. NGC 5195 appears as a very strong point source while its spectrum is dominated by the so-called PAH features at 6.2, 7.7, 8.6, and 11.3µm. No hot continuum is detected longward of 14µm, and infrared ionic lines are absent from the spectrum. We examine in…
DA white dwarfs in pointed observations from the ROSAT archive.
Wolff, B.; Jordan, S.; Koester, D.
87 pointed PSPC (Position Sensitive Proportional Counter) observations of hot DA white dwarfs, available in the ROSAT public archive until the end of 1994, have been analyzed together with Wide Field Camera (WFC) and EXOSAT data. From the 57 objects with a significant count rate half of the objects have a temperature below 38,000K and a virtually …
ISM parameters in the normal galaxy NGC 5713.
Helou, G.; Lord, S. D.; Malhotra, S. +11 more
We report ISO Long Wavelength Spectrometer (LWS) observations of the Sbc galaxy NGC 5713. We have obtained strong detections of the fine-structure forbidden transitions [CII] 158µm, [OI] 63µm, and [OIII] 88µm, and significant upper limits for [NII] 122µm, [OIII] 52µm, and [NIII] 57µm, and have measured the galax…
Observations of galactic cosmic rays and the anomalous helium during ULYSSES passage from the south to the north solar pole.
Simpson, J. A.; McKibben, R. B.; Zhang, M. +2 more
We compare observations of the modulated intensities and spectra of galactic cosmic ray nuclei and anomalous helium above 30 MeV/n measured by the COsmic and Solar Particle INvestigations (COSPIN) High Energy Telescope (HET) on Ulysses with similar observations from the IMP-8 earth-orbiting satellite between September 1994 and August 1995. During …
The SWS survey for rotational H_2_ lines in late-type galaxies. Observations of the central regions of NGC 6946.
de Graauw, T.; van der Werf, P. P.; de Jong, T. +1 more
We report the first extragalactic detection of the pure rotational H_2_ S(0) and S(1) lines at 28.2 and 17.0µm in the central 130pc molecular complex of the nearby Scd galaxy NGC 6946. We deduce a temperature of this gas component of 170K and a mass of 5x10^6^Msun_ for an ortho/para ratio of 3, corresponding to the ratio of statis…
Extragalactic symbiotic systems. III. The stellar components of the systems in the Magellanic Clouds.
Vogel, M.; Schild, H.; Muerset, U.
We present multifrequency data, ranging from ultraviolet and optical spectroscopy to infrared photometry, of the confirmed symbiotic systems in both Magellanic Clouds (SMC1, SMC2, SMC3, N60, Ln358, N73, S154, S147, LMC1, N67, and S63), as well as of Sanduleak's star, whose nature remains unclear. Because of the known distance, the Magellanic symbi…
Bimodal dust emission in three classical Seyfert galaxies: NGC 3227, NGC 4051 and NGC 4151.
Meisenheimer, K.; Lemke, D.; Rodriguez Espinosa, J. M. +1 more
Far Infrared observations of the Seyfert galaxies NGC 3227, NGC 4051 and NGC 4151 are presented. These are the first data from a complete sample of Seyfert galaxies that is being observed by ISO as part of the ISOPHOT guaranteed time. The new ISO data, in combination with the IRAS data, show that the mid to far IR emission in all three objects can…
Iron and nickel abundances of subluminous O-stars. I. NLTE-model atmospheres with line blanketing by iron group elements.
Werner, K.; Dreizler, S.; Heber, U. +2 more
NLTE model atmospheres for hot evolved stars including line blanketing of all iron group elements were first constructed by Dreizler & Werner (1993). In this paper we improve computational details and check the adopted simplifications. We also present a systematic investigation of the consequences of iron group line blanketing on the atmospher…