Results 21 to 30 of about 232,000 (280)

Hard synchrotron BL Lacs: the case of 1ES 1101-232 [PDF]

, 2000
The bright X-ray selected BL Lac object 1ES1101--232 shows a flat X-ray spectrum, making it detectable with high statistics over the wide BeppoSAX energy range.
Caccianiga, Alessandro, Ghisellini, Gabriele, Tagliaferri, Gianpiero, Tavecchio, Fabrizio, Wolter, Anna   +4 more
core   +3 more sources

Period Change of the Contact Binary AH Tauri [PDF]

Journal of Astronomy and Space Sciences, 2004
New BVRI photometric observations of the contact binary AH Tau were performed with the 61 cm reflector and a 2K CCD camera at the Sobaeksan Optical Astronomy Observatory during seven nights from September to December, 2001. A total of 144 times of minima
Dongjoo Lee, Chung-Uk Lee, Jae Woo Lee, Seung-Lee Kim, Kyu-Dong Oh, Chun-Hwey Kim   +5 more
doaj   +1 more source

Structural-parametric model of electromagnetoelastic actuator for astrophysics and optical astronomy [PDF]

Journal of Astrophysics & Aerospace Technology, 2017
Abstract The impossibility of a gravitational equilibrium of clusters of galaxies was the main argument supporting the existence of Dark Matter. However, the expansion of Universe is also a main element of evolution of clusters and it leads to a dispersion of these large structures at a rate that is slower than the expansion itself: the ...
Piersanti M, Cesaroni C, Spogli L, Alberti T, Di Matteo S   +4 more
openaire   +34 more sources

Close Binary System GO Cyg [PDF]

, 2011
In this study, we present long term photometric variations of the close binary system \astrobj{GO Cyg}. Modelling of the system shows that the primary is filling Roche lobe and the secondary of the system is almost filling its Roche lobe.
B. Kalomeni, B. Ulaş, Cester, Chochol, Drilling, Edalati, Eggleton, Elkhateeb, Erdem, Erkan, Hall, Irwin, Jassur, Jones, K. Yakut, Kalomeni, Köse, Lee, Lee, Lucy, Mannino, O. Köse, Oh, Oprescu, Ovenden, Payne-Gaposchkin, Pearce, Pierce, Pols, Popper, Pribulla, Prs˜a, Rovithis, Rovithis-Livaniou, Rucinski, Schneller, Sezer, Sezer, Torres, V. Keskin, van Hamme, von Zeipel, Vukasović, Wilson, Wronka, Yakut, Yakut, Zabihinpoor, Zhang   +48 more
core   +2 more sources

Atmospheric Optical Turbulence Characteristics over the Ocean Relevant to Astronomy and Atmospheric Physics

Applied Sciences, 2021
Due to the space and time constraints of turbulence measurement equipment and the experiment scene, it is difficult to obtain the atmosphere refractive index structure constant over the ocean.
Manman Xu, Shiyong Shao, Ningquan Weng, Liangping Zhou, Qing Liu, Yuefeng Zhao   +5 more
doaj   +1 more source

Light Curve Analysis of SAO23229 [PDF]

Journal of Astronomy and Space Sciences, 1993
We have made UBV light curves of a newly discovered eclipsing binary, SAO23229 at Sobaeksan Astronomy Observatory. We determined a minimum light time of HJD2448636.1170+/-0.0005 that is 3 minutes later than predicted time, and founda peculiar light ...
Ho-Il Kim, Woo-Baik Lee, Eon-Chang Sung, Chun-Hwey Kim   +3 more
doaj  

Heliocentric Potential (HCP) Prediction Model for Nowscast of Aviation Radiation Dose [PDF]

Journal of Astronomy and Space Sciences, 2015
It is well known that the space radiation dose over the polar route should be carefully considered especially when the space weather shows sudden disturbances such as CME and flares.
Junga Hwang, Kyung-Chan Kim, Kyunghwan Dokgo, Enjin Choi, Hang-Pyo Kim   +4 more
doaj   +1 more source

A planetary companion around the K giant eps Corona Borealis

, 2012
Aims. Our aim is to search for and study the origin of the low-amplitude and long-periodic radial velocity (RV) variations in K giants. Methods. We present high-resolution RV measurements of K2 giant epsilon CrB from February 2005 to January 2012 using ...
B.-C. Lee, Bertelli, D. E. Mkrtichian, da Silva, de Medeiros, Donati, Döllinger, Döllinger, Fischer, Frink, Gettel, Ghezzi, Girardi, Glazunova, Han, Han, Hatzes, Hatzes, Hatzes, Hekker, I. Han, Ida, Johnson, Johnson, Johnson, Johnson, Jørgensen, K.-M. Kim, Kim, Kürster, Lee, Lomb, Lovis, M.-G. Park, Massarotti, Mitchell, Moutou, Niedzielski, Pasquini, Pasquini, Piskunov, Quirrenbach, Reffert, Reiners, Richichi, Saar, Santos, Sato, Sato, Sato, Scargle, Setiawan, Setiawan, Shaya, Sozzetti, Takeda, Tody, Wittenmyer   +57 more
core   +1 more source

The Host Galaxy Fluxes of Active Galaxy Nuclei Are Generally Overestimated by the Flux Variation Gradient Method

Universe
In terms of the variable nature of normal active galaxy nuclei (AGN) and luminous quasars, a so-called flux variation gradient (FVG) method has been widely utilized to estimate the underlying non-variable host galaxy fluxes.
Minxuan Cai, Zhen Wan, Zhenyi Cai, Lulu Fan, Junxian Wang   +4 more
doaj   +1 more source

Design of a hybrid NAR-RBFs neural network for nonlinear dusty plasma system

Alexandria Engineering Journal, 2020
Robust modeling of a multimodal dynamic system is a challenging and fast-growing area of research. In this study, an integrated bi-modal computing paradigm based on Nonlinear Autoregressive Radial Basis Functions (NAR-RBFs) neural network model, a new ...
Ayaz Hussain Bukhari, Muhammad Sulaiman, Muhammad Asif Zahoor Raja, Saeed Islam, Muhammad Shoaib, Poom Kumam   +5 more
doaj   +1 more source