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Eclipse Mapping of Symbiotic Binaries
Crowley, C.; Espey, B.
We describe an ultraviolet eclipse mapping of the symbiotic binary EG And. Analysis of FUSE and HST/STIS observations at differing orbital phases probe different layers of the chromosphere and wind of the red giant in absorption. Whilst the primary aim of the study is to examine the thermal and dynamic conditions at the base of these winds, much i…
Catalog of red clump candidates in Tycho-2
Rybka, S. P.
We present the technique we used to compile a catalog of about 61 000 local stars brighter than Ks = 8.2m which were identified as most likely red clump candidates on the basis of their reduced proper motions in the Ks band. The catalog was compiled from the combined Tycho-2 and 2MASS data for the stars with color …
Wave excitation and turbulence at the Earth's bow shock: cluster data and simulations
Kucharek, H.; Möbius, E.; Miao, B.
Wave-particle interactions are the major player in shock formation, particle reflection and acceleration, downstream thermalization, and wave excitation. In particular, the foreshock is characterized by extensive wave activity, which is caused by the interaction of the backstreaming particles with the inflowing solar wind. This interaction causes …
Modelling of light and radial velocity curves in close binary systems: masses of stars and relativistic objects
Antokhina, E. A.
Synthesis methods for close binary systems allow the fundamental parameters of stars and relativistic objects to be reliably determined. The masses of massive hot stars and relativistic objects are of special interest in order to test stellar evolution theories. We present the results of light curve analysis, which allows us to determine stellar m…
(im)Balance of Forces in the Corona
Sylwester, B.; Sylwester, J.
Observed pattern of variability of solar atmosphere plasma structures, often accompanied by respective measured Doppler shifts, provides a direct evidence of imbalanced forces acting in this environment. Observed motions have been studied in various energy bands, extending from radio to hard X-rays using ground and space-borne instruments. Here, w…
Intrinsic spectra of the AXPs: De-extinction from model-independent measurement of interstellar column densities
Durant, Martin
Using direct measurements of photo-electric absorption edges, I derive the intrinsic spectra for the Anomalous X-ray Pulsars. In the past, the hydrogen column density, NH had been found by fitting the X-ray spectra with a variety of simple continuum models. Since different models fit equally well, with different values of NH,…
Winds from super star clusters: The interstellar environment in the starburst core of M82
Smith, L. J.; Westmoquette, M. S.
We present HST/STIS spectroscopy for two slit positions crossing the starburst core of M82, sampling both clusters and ionized gas at optical wavelengths. The spectra have a spatial resolution of ∼2 pc at M82, allowing us to probe the conditions within the starburst environment in unprecedented detail. The data provide new insights into young clus…
New Insights Into the Dynamics and Expansion Parallax of Nebulae around Symbiotic Stars
Corradi, R. L. M.; Santander-García, M.
Currently, there are a dozen known spatially resolved nebulae around symbiotic stars. We summarize their properties, focusing on their dynamical ones. Then, new results about the determination of the expansion in the plane of the sky of the nebulae around Hen 2-104 and Hen 2-147, which allows us to gain important information about their dynamics a…
SWAN observations of 9P/Tempel 1 around the Deep Impact event
Bertaux, Jean-Loup; Combi, Michael R.; Mäkinen, J. Teemu T. +2 more
The SWAN instrument observed the coma of Comet 9P/Tempel 1 at Lyman alpha around the Deep Impact event. From these observations, a water production rate profile for 3 weeks after the impact was derived. The comet could not be identified in images taken before the impact because of the relatively low production rates. The most important feature of …
Cluster Observation and Analysis of Bifurcation Current Sheet Structure in a Quiet Time
Lu, Li; Tang, Chao-Ling; Li, Zhong-Yuan
We analyse the vertical structure of the magnetotail current sheet during 2011 2030 UT on 19 August 2001, during which the Cluster spacecrafts crossed the current sheet in a quiet time. In the intervals, the current sheet moved slowly, and the value of the AE index was relatively small, about 40 130 nT. In the quiet time, without fast plasma flow …