Search Publications
Spectral behavior of AE Aqr between high and low states in the UV
Sanad, M. R.
We present ultraviolet spectra of the AE Aqr binary system taken by the International Ultraviolet Explorer (IUE) during the period from 1978 to 1993, to accomplish a large scale study of what happens to the ultraviolet fluxes of different emission lines during different orbital phases. Five profiles of AE Aqr binary system show variations of line …
Physical mechanisms of the spectral variability of α Orionis with IUE
Sanad, M. R.
We present a spectroscopic study of Mg II k&h emission lines in the 2000-3000 Å region of 91 high resolution IUE spectra of α Orionis obtained during the period 1978-1996. There are absorption and emission components on the blue sides of the k&h emission lines, these components may be coming from the dust envelope located inside the extend…
Spectral variability of the α Sco AB binary system observed with IUE
Sanad, M. R.; Bobrowsky, M.
We present ultraviolet spectra of the α Sco AB binary system taken by the International Ultraviolet Explorer during the period from 1979 to 1995. An investigation is carried out on the spectral variability of Mg II k and h emission lines arising from the chromosphere of α Sco A ( Van der Hucht et al., 1979). There are absorption and emission compo…
Disparity of spectral behavior of RR Tel and RX Pup in the UV
Sanad, M. R.
The main aim of this study is to use archival low-dispersion spectra from the International Ultraviolet Explorer (IUE) in an attempt to follow up the spectral behavior of two symbiotic Mira systems RR Tel and RX Pup of the period from 1978-1995 and 1979-1989 for two systems respectively. We concentrated on studying N IV 1486 Å intercombination lin…
Eclipsing and density effects on the spectral behavior of Beta Lyrae binary system in the UV
Sanad, M. R.
We analyze both long and short high resolution ultraviolet spectrum of Beta Lyrae eclipsing binary system observed with the International Ultraviolet Explorer (IUE) between 1980 and 1989. The main spectral features are P Cygni profiles originating from different environments of Beta Lyrae. A set of 23 Mg II k&h spectral lines at 2800 Å, origin…
Calculation of the local standard of rest from 20 574 local stars in the New Hipparcos Reduction with known radial velocities
Francis, Charles; Anderson, Erik
ContextAn accurate estimate of the local standard of rest (LSR) is required to determine key parameters used in approximate galactic mass models and to understand Galactic structure and evolution. However, authors are often forced to base dynamical analyses on potentially unreliable figures because recent determinations of the LSR have failed to r…
On some properties of coronal mass ejections in solar cycle 23
Mittal, Nishant; Narain, Udit
We have investigated some properties such as speed, apparent width, acceleration, latitude, mass and kinetic energy, etc. of all types of coronal mass ejections (CMEs) observed during the period 1996-2007 by SOHO/LASCO covering the solar cycle 23. The results are in satisfactory agreement with previous investigations.
A W UMa type system from Southern Hemisphere: CN Hydri
Bakış, V.; Özkardeş, B.; Erdem, A.
We present an analysis of the Hipparcos photometry and the high-resolution ( {λ}/{Δλ}=41000) spectroscopy of the W UMa type system CN Hyi obtained in this study for the first time. The high resolution spectroscopic observations of the system were made at Mt. John University Observatory by using HERCULES fibre-fed échelle spectrograph in September …
The data mining: An analysis of 20 eclipsing binary light-curves observed by the INTEGRAL/OMC
Zasche, P.
Twenty eclipsing binaries were selected for an analysis from a huge database of observations made by the INTEGRAL/OMC camera. The photometric data were processed and analyzed, resulting in a first light-curve study of these neglected eclipsing binaries. Most of the selected systems are the detached ones. The system ET Vel was discovered to be an e…
Automated star-galaxy segregation using spectral and integrated band data for TAUVEX/ASTROSAT satellite data pipeline
Singh, Harinder P.; Gupta, Ranjan; Bora, Archana +1 more
We employ an Artificial Neural Network (ANN) based technique to develop a pipeline for automated segregation of stars from the galaxies to be observed by Tel-Aviv University Ultra-Violet Experiment (TAUVEX). We use synthetic spectra of stars from UVBLUE library and selected International Ultraviolet Explorer (IUE) low-resolution spectra for galaxi…