ﻻ يوجد ملخص باللغة العربية
We report high resolution spectral observations of the yellow symbiotic star V417 Cen obtained in 2004. We find that the equivalent widths of the emission lines decreased, while the brightness increased. The FWHMs and wavelengths of the emission lines do not change. We estimated the interstellar extinction towards V417 Cen as $E_{B-V}$ = 0.95 $pm$0.10, using the KI interstellar line. Using the [O III] lines, we obtain a rough estimation of the density and the temperature in the forbidden lines region $log N_e approx 4.5 pm$ 0.5 and $T_e=100000 pm 25000$~K. Tidal interaction in this binary is also discussed.
We present results from the most comprehensive radio monitoring campaign towards the closest star to our Sun, Proxima Centauri. We report 1.1 to 3.1 GHz observations with the Australian Telescope Compact Array over 18 consecutive days in April 2017.
The detection of narrow SiO thermal emission toward young outflows has been proposed to be a signature of the magnetic precursor of C-shocks. Recent modeling of the SiO emission across C-shocks predicts variations in the SiO line intensity and line s
Results of a long-term monitoring ($gtrsim 10$ years) of the broad line and continuum fluxes of three Active Galactic Nuclei (AGN), 3C 390.3, NGC 4151, and NGC 5548, are presented. We analyze the H$alpha$ and H$beta$ profile variations during the mon
The narrow [O III] 4959, 5007 emission-line fluxes in the spectrum of the well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this we show that the narrow line-emitting region has a radius of only 1-3 pc and is denser (n ~ 10^5 c
We present cosmological parameter measurements from the effective field theory-based full-shape analysis of the power spectrum of emission line galaxies (ELGs). First, we perform extensive tests on simulations and determine appropriate scale cuts for