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Spectroscopic and photometric observations of the selected Algol-type binaries - II. V2080 Cygni and V2365 Ophiuchi
Frasca, A.; Çakırlı, Ö.; Sipahi, E. +9 more
This paper is the second in the planned series of investigations. We present new radial velocities and photometric observations of V2080 Cyg and V2365 Oph. New UBV photometric data and radial velocities were analysed for the systems' parameters. While V2080 Cyg consists of two nearly equal F-type main-sequence stars, V2365 Oph has two different co…
The iron abundance of the Magellanic Bridge
Dufton, P. L.; Thompson, H. M. A.; Ryans, R. S. I. +1 more
High-resolution Hubble Space Telescope ultraviolet spectra for five B-type stars in the Magellanic Bridge and in the Large (LMC) and Small (SMC) Magellanic Clouds have been analysed to estimate their iron abundances. Those for the Clouds are lower than estimates obtained from late-type stars or the optical lines in B-type stars by approximately 0.…
A Comparison of Feature Classification Methods for Modeling Solar Irradiance Variation
Harvey, K. L.; Pap, J. M.; Jones, H. P. +4 more
Physical understanding of total and spectral solar irradiance variation depends upon establishing a connection between the temporal variability of spatially resolved solar structures and spacecraft observations of irradiance. One difficulty in comparing models derived from different data sets is that the many ways for identifying solar features su…
Physical parameters for Orion KL from modelling its ISO high-resolution far-IR CO line spectrum
White, G. J.; Barlow, M. J.; Cernicharo, J. +5 more
As part of the first high-resolution far-infrared (far-IR) spectral survey of the Orion Kleinmann-Low (KL) region, we observed 20 CO emission lines with Jup = 16 to 39 (upper levels from ~752 to 4294 K above the ground state). Observations were taken using the Long Wavelength Spectrometer on board the Infrared Space Observatory (ISO), i…
A Study of H2 Emission in Three Bipolar Proto-Planetary Nebulae: IRAS 16594-4656, Hen 3-401, and Rob 22
Smith, Nathan; Hrivnak, Bruce J.; Su, Kate Y. L. +1 more
We have carried out a spatial-kinematic study of three proto-planetary nebulae, IRAS 16594-4656, Hen 3-401, and Rob 22. High-resolution H2 images were obtained with NICMOS on the Hubble Space Telescope, and high-resolution spectra were obtained with the Phoenix spectrograph on Gemini-South. IRAS 16594-4656 shows a "peanut-shaped" bipola…
Density of discontinuities in the heliosphere
Balogh, A.; ErdőS, G.
The spatial distribution of MHD discontinuities in the solar wind has been studied, based on the long time observations by the magnetometer onboard Ulysses. We emphasize the critical importance of the method whereby events are selected; some previous work is critically reviewed in this respect. Our analysis supports earlier observations that the d…
Synthetic radio maps of CME-driven shocks below 4 solar radii heliocentric distance
Gopalswamy, N.; Schmidt, J. M.
We present 2 1/2 D numerical MagnetoHydroDynamic (MHD) simulations of coronal mass ejections (CMEs) in conjunction with plasma simulations of radio emission from the CME-driven shocks. The CME-driven shock extends to an almost spherical shape during the temporal evolution of the CME. Our plasma simulations can reproduce the dynamic spectra of coro…
Correlated spectral variability in brown dwarfs
Bailer-Jones, C. A. L.
Models of brown dwarf atmospheres suggest they exhibit complex physical behaviour. Observations have shown that they are indeed dynamic, displaying small photometric variations over time-scales of hours. Here, I report results of infrared (0.95-1.64 µm) spectrophotometric monitoring of four field L and T dwarfs spanning time-scales of 0.1-5.…
Large-scale horizontal flows in the solar photosphere. II. Long-term behaviour and magnetic activity response
Švanda, M.; Sobotka, M.; Klvaňa, M. +1 more
We have developed a method to map large-scale horizontal velocity fields in the solar photosphere. The method was developed, tuned, and calibrated using synthetic data. Now, we apply the method to the series of Michelson Doppler Imager (MDI) Dopplergrams covering almost one solar cycle to generate the information about the long-term behaviour of s…
A Chandra Look at Five of the Broadest Double-Peaked Balmer Line Emitters
Brandt, W. N.; Eracleous, Michael; Garmire, Gordon +1 more
We study the 0.5-10 keV emission of a sample of five of the broadest double-peaked Balmer line emitters with Chandra. The Balmer lines of these objects originate close (within a few hundred gravitational radii) to the central black holes of the active galactic nuclei (AGNs), and their double-peaked profiles suggest an origin in the AGN accretion d…