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XMM-Newton and Swift observations of the Seyfert 1 AGN NGC 5940
Adegoke, Oluwashina K.
Probing the physics of the accretion flow around active galactic nuclei (AGN) is crucial to understanding their emission mechanisms as well as being able to constrain the geometrical and variability properties of the different regions around them. The soft X-ray excess – usually observed below
The mass profile of NGC 3377 from a Bayesian approach
Caso, Juan P.
The mass profile for the moderately bright elliptical NGC 3377 is studied through a spherical Jeans analysis, combined with a Bayesian approach. The prior distributions are generated from dark matter simulations and observational constraints. The observational data set consist of Gemini/Gemini Multi-Object Spectrograph long-slit observations align…
Dynamical Architecture of the HD 107148 Planetary System
Trifonov, Trifon; Stock, Stephan; Henning, Thomas +15 more
We present an independent Doppler validation and dynamical orbital analysis of the two-planet system HD 107148, which was recently announced in Rosenthal et al. Our detailed analyses are based on literature HIRES data and newly obtained HARPS and CARMENES radial-velocity (RV) measurements as part of our survey in search for additional planets arou…
Seasonal Variations of Chemical Species and Haze in Titan's Upper Atmosphere
Fan, Siteng; Zhao, Daniel; Li, Cheng +3 more
Seasonal variation is significant in Titan's atmosphere owing to the large change of solar insolation resulting from Titan's 26.7° axial tilt relative to the plane of Saturn's orbit. Here we present an investigation of hydrocarbon and nitrile species in Titan's upper atmosphere at 400-1200 km, which includes the mesosphere and the lower thermosphe…
Oymaklardaki Yıldızların Fiziksel Özellikleri Üzerine: Yukarı Akrep Örneği
BAKIŞ, Volkan
Yıldız oymakları ve açık kümeler gibi yıldız topluluklarındaki üye yıldızların fiziksel parametrelerine ulaşmak bizi topluluğa ait temel fiziksel parametrelere (örn. yaş, başlangıç kütle fonksiyonu) götürür. Bu parametreler de galaksimizin dinamiğini anlamamız açısından gereklidir. Bu çalışmada yıldızların fiziksel özelliklerine (sıcaklık, yarıçap…
A dynamical evolution study of the open clusters: Berkeley 10, Berkeley 81, Berkeley 89 and Ruprecht 135
Çakmak, Hikmet; Karataş, Yüksel
By utilizing Gaia EDR3 photometric/astrometric data, we studied the dynamical evolution from the obtained astrophysical, structural and dynamical parameters of the open clusters (OCs), Berkeley 10 (Be 10), Berkeley 81 (Be 81), Berkeley 89 (Be 89), and Ruprecht 135 (Ru 135). The Gaia EDR3 photometric distances from the isochrone fitting method are …
BFS 10: a nascent bipolar H II region in a filamentary molecular cloud
Kerton, C. R.; Larose, Nicholas
We present a study of the compact blister H II region BFS 10 and its highly filamentary molecular cloud. We utilize 12CO observations from the Five College Radio Astronomy Observatory to determine the distance, size, mass, and velocity structure of the molecular cloud. Infrared observations obtained from the UKIRT Infrared Deep Sky Surv…
Spectral Behavior and Flaring Activity of II Peg in the Ultraviolet
Sanad, M. R.
We have studied the spectral behavior of the II Peg binary system in the ultraviolet band by using International Ultraviolet Explorer (IUE) observations over the period 1979-1993. The ultraviolet observations reveal indication of flare activity in both chromosphere and transition region with their enhanced emission lines. Before and after the flar…
Investigating the effect of surface - exosphere interactions
Johnson, R. E.; Chaufray, J. -Y.; Leblanc, F. +3 more
The surface of planetary airless bodies, also called surface bounded exosphere, like our Moon or Mercury, are directly bombarded by solar particles. The most abundant of those particles are solar wind protons. In the case of the Moon, many observations of low energy neutral atoms have shown that a significant portion of these incident protons are …
Revisiting the high-mass transfer close binary star system AU Monocerotis
Shore, Steven N.; Armeni, Antonio
Context. AU Monocerotis is an eclipsing, double-lined spectroscopic binary with a period of 11 days that is in a state of extreme mass transfer, consisting of a main sequence B-type embedded in a thick accretion disk fed by a Roche lobe overflowing evolved G-type companion. It is also one of the double periodic variable Algol-type binaries.
A…