Search Publications
ISOCAM CVF observations of the Quintuplet and Object#17 clusters near the Galactic Center.
Kawara, K.; Onaka, T.; Okuda, H. +2 more
Two fields near the Galactic Center, containing the Quintuplet and Object #17 star-clusters, have been imaged with the ISOCAM circular variable filters (CVFs) in the wavelength range of 2.47-3.08µm and 3.99-9.09µm. Emission of [Ar II] 6.99µm is detected in the "pistol-shaped" H II region (G0.15-0.05) to the south of the Quintuple…
Interplanetary discontinuities in corotating streams and their interaction regions.
Balogh, A.; Tsurutani, B. T.; Goldstein, B. E. +3 more
In this study, we investigate the discontinuity properties in the low latitude corotating stream regions which are encountered during Ulysses traveling from the south to north heliographic poles in 1995. Through the occurrence rates of directional discontinuities and tangential discontinuities, we find that there are three different regions around…
Proper motion study of the globular cluster M 92.
Tucholke, H. -J.; Scholz, R. -D.; Brosche, P.
We present proper motions for stars in the field of the galactic globular cluster NGC6341 (M92). This study continues the series of papers from the Bonn programme of globular cluster proper motions. Plates taken with the Bonn double refractor and the Rozhen observatory 2m Ritchey-Chretien telescope with a maximal epoch difference of 94years were u…
Optical spectra of ζ Aurigae systems. VIII. The chromosphere of HR6902.
Schroeder, K. -P.; Griffin, R. E. M.; Marshall, K. P.
We analyze chromospheric spectra of the ζ Aur system HR6902 observed during its 1987 and 1989 eclipses, deriving empirical column densities, number densities and ionization characteristics for 5 distinct heights within the giant primary's chromosphere. Column densities for CaII are determined from K-line profiles and for other ions by a curve-of-g…
ISOCAM imaging of AG CAR and HR Car.
Waters, L. B. F. M.; Trams, N. R.; Voors, R. H. M.
We present infrared images obtained with the ISOCAM instrument on board the Infrared Space Observatory of two Luminous Blue Variables (AG Car and HR Car). The images were obtained at eight wavelengths between 8.5 and 16µm using the Circular Variable Filters (CVFs), with a pixel size of 6 by 6arcsec and a total field of view of 192 by 192arcs…
Interstellar atom and pick-up ion fluxes along the ULYSSES flight-path.
Fichtner, H.; Mall, U.; Rucinski, D.
Neutral atom and pick-up ion flux computations using a hot model for hydrogen, helium, oxygen and neon along the trajectory of the Ulysses spacecraft, including predictions for the Extended Mission are reported and discussed. The feasibility of using absolute pick-up ion fluxes and pick-up ion flux ratios to derive the orientation of the heliosphe…
NLTE treatment of calcium in the Monte Carlo modeling of early-time spectra of SN 1993J.
Zhang, Q.; Wang, Z. R.
NLTE treatment of calcium with five lower bound energy levels of Ca II and the ionization state of Ca III is annexed to the Monte Carlo model to improve our study on the early-time spectra of SN 1993J. This NLTE + Monte Carlo code is employed in modeling the ultraviolet and optical spectra of SN 1993J obtained simultaneously on 1993 April 15 by th…
Joint ULYSSES and WIND observations of a particle event in April 1995.
Simnett, G. M.; Pick, M.; Bothmer, V. +5 more
In this paper we analyze a solar particle event that was measured at two locations in the heliosphere. Ulysses was at 40°north heliolatitude and 130°west in heliolongitude from Earth while WIND was near Earth at 1 AU in the ecliptic plane. To establish the origin of the particle events, solar coronal activity is investigated. Direct observational …
Absolute magnitudes and kinematics of oxygen Mira variables.
Luri, X.; Figueras, F.; Torra, J. +1 more
A new maximum likelihood method, using apparent magnitudes, proper motions and radial velocities, has been applied to a sample of 90 Mira stars extracted from the HIPPARCOS Input Catalogue (INCA) to determine absolute magnitudes and kinematics. Using this new method three different groups of Mira stars have been identified in the sample, with diff…
Coronal diffusion and high solar latitude recurrent energetic particle increases.
Keppler, E.; Fraenz, M.; Quenby, J. J. +2 more
Ulysses observations have demonstrated that energetic particle flux increases are not only found to be associated with the regularly appearing recurrent fast streams seen at mid solar latitudes but also that they persist with the same periodicity of occurrence to at least 64° latitude, well into the region where no accompanying plasma speed enhanc…